Protein Information

Name Acetylcholinesterase
Synonyms ACHE; ACHE protein; AChE; ARACHE; AcChoEase; Acetylcholine acetylhydrolase; Acetylcholinesterase; Acetylcholinesterase isoform E4 E6 variant…

Compound Information

Name trichlorfon
CAS

Reference List

PubMed Abstract RScore(About this table)
11099780 Pakaski M, Rakonczay Z, Kasa P: Reversible and irreversible acetylcholinesterase inhibitors cause changes in neuronal amyloid precursor protein processing and protein kinase C level in vitro. Neurochem Int. 2001 Mar;38(3):219-26.

5(0,0,0,5) Details
9585171 Cutler NR, Jhee SS, Cyrus P, Bieber F, TanPiengco P, Sramek JJ, Gulanski B: Safety and tolerability of metrifonate in patients with Alzheimer's disease: results of a maximum tolerated dose study. Life Sci. 1998;62(16):1433-41.


Metrifonate, a pro-drug that is transformed non-enzymatically into a potent inhibitor of acetylcholinesterase (AChE), has been used in the tropics for over 30 years for the treatment of schistosomiasis.
5(0,0,0,5) Details
7234252 Sadovnikova LD, Anders VN, Sal'nikov VV: [Effect of anticholinesterases on acetylcholinesterase distribution in the human and animal brain (cytochemical study)]. Zh Nevropatol Psikhiatr Im S S Korsakova. 1981;81(2):108-14.

5(0,0,0,5) Details
12794734 Decossas M, Bloch B, Bernard V: Trafficking of the muscarinic m2 autoreceptor in cholinergic basalocortical neurons in vivo: differential regulation of plasma membrane receptor availability and intraneuronal localization in acetylcholinesterase-deficient and -inhibited mice. J Comp Neurol. 2003 Jun 9;462(3):302-14.

5(0,0,0,5) Details
7199685 Olajos EJ, Rosenblum I: Membrane-bound and soluble esterase activities in various hen brain regions after diisopropyl phosphorofluoridate and trichlorfon treatment. Neurotoxicology. 1981 Nov;2(3):463-70.

Acetylcholinesterase, neurotoxic esterase, and nonspecific esterase activities were studied in subcellular fractions obtained from homogenates of forebrain, cerebellum, and brainstem areas of hen brain.
4(0,0,0,4) Details
16822217 Dhingra D, Parle M, Kulkarni SK: Comparative brain cholinesterase-inhibiting activity of Glycyrrhiza glabra, Myristica fragrans, ascorbic acid, and metrifonate in mice. J Med Food. 2006 Summer;9(2):281-3.


Acetylcholinesterase is an enzyme that inactivates acetylcholine.
4(0,0,0,4) Details
15630588 Prickaerts J, Sik A, van der Staay FJ, de Vente J, Blokland A: Dissociable effects of acetylcholinesterase inhibitors and phosphodiesterase type 5 inhibitors on object recognition memory: acquisition versus consolidation. Psychopharmacology. 2005 Feb;177(4):381-90. Epub 2004 Jul 24.

4(0,0,0,4) Details
10507245 Heinig R, Sachse R: The effect of food and time of administration on the pharmacokinetic and pharmacodynamic profile of metrifonate. Int J Clin Pharmacol Ther. 1999 Sep;37(9):456-64.


AUC and Cmax of metrifonate and DDVP as primary parameters were compared between treatments by ANOVA and acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibition vs. time profiles were assessed.
2(0,0,0,2) Details
4656609 Bueding E, Liu CL, Rogers SH: Inhibition by metrifonate and dichlorvos of cholinesterases in schistosomes. Br J Pharmacol. 1972 Nov;46(3):480-7.


Administration of a possible metabolite of metrifonate, dichlorvos, to hamsters resulted in a greater inhibition of AChE and ChE activities of S. haematobium than those of S. mansoni.
2(0,0,0,2) Details
9758325 Piecoro LT, Wermeling DP, Schmitt FA, Ashford JW: Seizures in patients receiving concomitant antimuscarinics and acetylcholinesterase inhibitor. Pharmacotherapy. 1998 Sep-Oct;18(5):1129-32.

4(0,0,0,4) Details
9718229 Kaufer D: Beyond the cholinergic hypothesis: the effect of metrifonate and other cholinesterase inhibitors on neuropsychiatric symptoms in Alzheimer's disease. Dement Geriatr Cogn Disord. 1998;9 Suppl 2:8-14.


Preliminary studies suggest that non-cognitive behavioural and personality alterations in Alzheimer's disease may benefit from agents which inhibit central acetylcholinesterase (AChE).
4(0,0,0,4) Details
1858789 Moriearty PL, Womack CL, Dick BW, Colliver JA, Robbs RS, Becker RE: Stability of peripheral hematological parameters after chronic acetylcholinesterase inhibition in man. Am J Hematol. 1991 Aug;37(4):280-2.

4(0,0,0,4) Details
2640774 Horsberg TE, Hoy T, Nafstad I: Organophosphate poisoning of Atlantic salmon in connection with treatment against salmon lice. Acta Vet Scand. 1989;30(4):385-90.

Three incidents with high mortality in Atlantic salmon after trichlorfon treatment against salmon lice are described.
The mean brain acetylcholinesterase (AChE) activity of dead fish was less than 20% of normal activity, while survivors showed mean activities of 22-61% of normal levels.
3(0,0,0,3) Details
10681099 Lesser J, Blodgett D, Ehrich M: Comparison of oxime-initiated reactivation of organophosphorous-inhibited acetylcholinesterase in brains of avian embryos. J Toxicol Environ Health A. 2000 Jan 14;59(1):57-66.

Doses of chlorpyrifos, parathion, acephate, and trichlorfon that inhibited AChE > 70% were administered to the embryos.
167(2,2,2,7) Details
46730 Silvestri R, Himes JA, Edds GT: Repeated oral administration of coumaphos in sheep: interactions of coumaphos with bishydroxycoumarin, trichlorfon, and phenobarbital sodium. Am J Vet Res. 1975 Mar;36(3):289-92.

The treatment of ewes with an intravenous (IV) injection of trichlorfon, insufficient to produce significant inhibition of erythrocyte acetylcholinesterase (AChE) activity, appeared to produce additive effects with those produced by subsequent treatment with 4 mg of coumaphos/kg/day.
81(1,1,1,1) Details
10718203 Blass JP, Cyrus PA, Bieber F, Gulanski B: Randomized, double-blind, placebo-controlled, multicenter study to evaluate the safety and tolerability of metrifonate in patients with probable Alzheimer disease. Alzheimer Dis Assoc Disord. 2000 Jan-Mar;14(1):39-45.


Metrifonate produced a mean erythrocyte acetylcholinesterase inhibition at the end of treatment of 86.3%.
3(0,0,0,3) Details
10365643 Dingemanse J, Halabi A, Kleinbloesem CH, Heinig R, Blume H: Pharmacokinetics and pharmacodynamics of the acetylcholinesterase inhibitor metrifonate in patients with renal impairment. Ther Drug Monit. 1999 Jun;21(3):310-6.

3(0,0,0,3) Details
10773217 Pakaski M, Rakonczay Z, Fakla I, Papp H, Kasa P: In vitro effects of metrifonate on neuronal amyloid precursor protein processing and protein kinase C level. Brain Res. 2000 Apr 28;863(1-2):266-70.


It has been suggested that acetylcholinesterase (AChE) inhibitors, which promote the cholinergic function and consequently improve the cognitive deficits, may also exert a neuroprotective effect by activating normal APP processing.
3(0,0,0,3) Details
8876775 Becker RE, Colliver JA, Markwell SJ, Moriearty PL, Unni LK, Vicari S: Double-blind, placebo-controlled study of metrifonate, an acetylcholinesterase inhibitor, for Alzheimer disease. Alzheimer Dis Assoc Disord. 1996 Fall;10(3):124-31.

3(0,0,0,3) Details
9268605 Ehrich M, Correll L, Veronesi B: Acetylcholinesterase and neuropathy target esterase inhibitions in neuroblastoma cells to distinguish organophosphorus compounds causing acute and delayed neurotoxicity. Fundam Appl Toxicol. 1997 Jul;38(1):55-63.

Inhibition of AChE was greater than inhibition of NTE, without overlap of the concentration-response curves, for OPs which are more likely to cause acute, rather than delayed, neurotoxic effects in vivo (e.g., chlorpyrifos-oxon, dichlorvos, and trichlorfon).
37(0,1,1,7) Details
18804659 Pohanka M, Jun D, Kuca K: Improvement of acetylcholinesterase-based assay for organophosphates in way of identification by reactivators. Talanta. 2008 Oct 19;77(1):451-4. Epub 2008 Jun 17.

The most significant identification was based on methamidophos inhibited AChE reactivation by HI-6 or pralidoxime and paraoxon-ethyl inhibited AChE by obidoxime; moreover, identification of trichlorfon and paraoxon-methyl was possible, too.
35(0,1,1,5) Details
11526466 Racchi M, Sironi M, Caprera A, Konig G, Govoni S: Short- and long-term effect of acetylcholinesterase inhibition on the expression and metabolism of the amyloid precursor protein. Mol Psychiatry. 2001 Sep;6(5):520-8.

3(0,0,0,3) Details
7498734 Nguyen M, Alfonso A, Johnson CD, Rand JB: Caenorhabditis elegans mutants resistant to inhibitors of acetylcholinesterase. Genetics. 1995 Jun;140(2):527-35.

3(0,0,0,3) Details
9515941 Ehrich M, Correll L: Inhibition of carboxylesterases in SH-SY5Y human and NB41A3 mouse neuroblastoma cells by organophosphorus esters. J Toxicol Environ Health A. 1998 Mar 13;53(5):385-99.

CbxE are thought to protect the critical enzyme acetylcholinesterase (AChE) from OP inhibition in animals.
Therefore, this study examined concentration-related OP-induced inhibition of CbxE in human SH-SY5Y and mouse NB41A3 neuroblastoma cells with 11 active esterase inhibitors: paraoxon, malaoxon, chlorpyrifos-oxon, tolyl saligenin phosphate (TSP), phenyl saligenin phosphate (PSP), diisopropyl phosphorofluoridate (DFP), mipafox, dichlorvos, trichlorfon, dibutyryl dichlorovinyl phosphate (DBVP), and dioctyl dichlorovinyl phosphate (DOVP).
3(0,0,0,3) Details
8783813 Worek F, Kirchner T, Backer M, Szinicz L: Reactivation by various oximes of human erythrocyte acetylcholinesterase inhibited by different organophosphorus compounds. Arch Toxicol. 1996;70(8):497-503.

For this purpose human erythrocyte AChE (EC 3.1.1.7) was inhibited (30 min) by chlorfenvinphos, dichlorvos, dicrotophos, heptenophos, mevinphos, monocrotophos, paraoxon, phosphamidon, trichlorfon, malaoxon, omethoate, oxydemeton-methyl or methamidophos by 85-98% of control.
34(0,1,1,4) Details
15992092 Ringman JM, Cummings JL: Metrifonate (Trichlorfon): a review of the pharmacology, pharmacokinetics and clinical experience with a new acetylcholinesterase inhibitor for Alzheimer's disease. Expert Opin Investig Drugs. 1999 Apr;8(4):463-71.
32(0,1,1,2) Details
18825528 Pohanka M, Jun D, Kuca K: In vitro reactivation of trichlorfon-inhibited butyrylcholinesterase using HI-6, obidoxime, pralidoxime and K048. J Enzyme Inhib Med Chem. 2008 Sep 29:1.

The presented study is aimed at reactivation of trichlorfon-inhibited butyrylcholinesterase since this enzyme play an important role in Alzheimer's disease as deputy for acetylcholinesterase and furthermore it could be applied as a scavenger in case of overdosing.
31(0,1,1,1) Details
15569517 Rui F, Zhou JF, Shao JM, Zhang XY, He JF: [Relationship between acute dipterex poisoning and oxidative stress and free radical damage.]. Zhonghua Yu Fang Yi Xue Za Zhi. 2004 Nov;38(6):419-21.


Plasma levels of vitamin C (VC) and vitamin E (VE), as well as level of lipoperoxide (LPO) and activities of superoxide dismutase (SOD) and acetylcholinesterase (AChE) in the red blood cells (RBC), were determined by spectrophotometry.
2(0,0,0,2) Details
19446058 Wei Y, Li Y, Qu Y, Xiao F, Shi G, Jin L: A novel biosensor based on photoelectro-synergistic catalysis for flow-injection analysis system/amperometric detection of organophosphorous pesticides. Anal Chim Acta. 2009 Jun 8;643(1-2):13-8. Epub 2009 Apr 5.

A wide linear inhibition response for trichlorfon was observed in the range of 0.01-20 microM with the detection limit of 0.1 nM.
The acetylcholinesterase enzyme (AChE) was immobilized by adsorption into the nanostructured PbO2/TiO2/Ti, which also acted as the working electrode.
2(0,0,0,2) Details
17055053 Guimaraes AT, Silva de Assis HC, Boeger W: The effect of trichlorfon on acetylcholinesterase activity and histopathology of cultivated fish Oreochromis niloticus. Ecotoxicol Environ Saf. 2007 Sep;68(1):57-62. Epub 2006 Oct 19.
13(0,0,2,3) Details
12974645 Jennings LL, Malecki M, Komives EA, Taylor P: Direct analysis of the kinetic profiles of organophosphate-acetylcholinesterase adducts by MALDI-TOF mass spectrometry. Biochemistry. 2003 Sep 23;42(37):11083-91.

9(0,0,0,9) Details
18569613 Rajini PS, Melstrom P, Williams PL: A comparative study on the relationship between various toxicological endpoints in Caenorhabditis elegans exposed to organophosphorus insecticides. J Toxicol Environ Health A. 2008;71(15):1043-50.

The toxicity of 10 organophophorus (OP) insecticides-acephate, dimethoate, dichlorvos, dicrotophos, monocrotophos, methamidophos, phosphamidon, omethoate, phosdrin, and trichlorfon-was evaluated in Caenorhabditis elegans using lethality, movement, and acetylcholinesterase (AChE) activity as the endpoints after a 4-hr- exposure period.
9(0,0,1,4) Details
14535624 Rakonczay Z: Potencies and selectivities of inhibitors of acetylcholinesterase and its molecular forms in normal and Alzheimer's disease brain. Acta Biol Hung. 2003;54(2):183-9.

8(0,0,0,8) Details
8159460 Camacho M, Tarrab-Hazdai R, Espinoza B, Arnon R, Agnew A: The amount of acetylcholinesterase on the parasite surface reflects the differential sensitivity of schistosome species to metrifonate. Parasitology. 1994 Feb;108 ( Pt 2):153-60.

7(0,0,0,7) Details
9823777 Tian Y, Xie XK, Piao FY, Yamauchi T: Delayed neuropathy and inhibition of soluble neuropathy target esterase following the administration of organophosphorus compounds to hens. Tohoku J Exp Med. 1998 Jul;185(3):161-71.


Delayed neuropathy and inhibition of soluble neuropathy target esterase (NTE) and acetylcholinesterase (AChE) activities in different regions of brain and spinal cord of adult hens were studied after the intravenous administration of leptophos (30 mg/kg), tri-o-cresyl phosphate (TOCP 40 mg/kg) or dipterex (200 mg/kg).
2(0,0,0,2) Details
15386949 Zhou JF, Zhou W, Zhang SM, Luo YE, Chen HH: Oxidative stress and free radical damage in patients with acute dipterex poisoning. Biomed Environ Sci. 2004 Jun;17(2):223-33.


METHODS: Fifty ADPPs and fifty healthy adult volunteers (HAVs) whose ages, gender and others were matched with the ADPPs were enrolled in a randomized controlled study, in which concentrations of nitric oxide (NO), vitamin C (VC), vitamin E (VE) and beta-carotene (beta-CAR) in plasma as well as concentration of lipoperoxide (LPO), and activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) and acetylcholinesterase (AChE) in erythrocytes were determined by spectrophotometric analytical methods.
2(0,0,0,2) Details
11665858 Shapira M, Thompson CK, Soreq H, Robinson GE: Changes in neuronal acetylcholinesterase gene expression and division of labor in honey bee colonies. J Mol Neurosci. 2001 Aug;17(1):1-12.

7(0,0,0,7) Details
12420757 Turdean GL, Popescu IC, Oniciu L, Thevenot DR: Sensitive detection of organophosphorus pesticides using a needle type amperometric acetylcholinesterase-based bioelectrode. J Enzyme Inhib Med Chem. 2002 Apr;17(2):107-15.

6(0,0,0,6) Details
12803484 Kim CS, Kim WT, Boo KS, Kim SI: Cloning, mutagenesis, and expression of the acetylcholinesterase gene from a strain of Musca domestica; the change from a drug-resistant to a sensitive enzyme. Mol Cells. 2003 Apr 30;15(2):208-15.

6(0,0,0,6) Details
10791297 Unni L, Vicari S, Moriearty P, Schaefer F, Becker R: The recovery of cerebrospinal fluid acetylcholinesterase activity in Alzheimer's disease patients after treatment with metrifonate. Methods Find Exp Clin Pharmacol. 2000 Jan-Feb;22(1):57-61.

6(0,0,0,6) Details
2640362 Kassa J, Stefanik M: [Methods of treating experimental Neguvon poisoning and a comparison of their effects]. Sb Ved Pr Lek Fak Karlovy Univerzity Hradci Kralove Suppl. 1989;32(4):481-91.


As a dialysate, the combination of ACHE reactivator with atropine, distilled water and ACHE preparation has been used.
6(0,0,0,6) Details
6871453 Braginskaia FI, Sultanova GG, Zorina OM: [Effect of chlorine-containing pesticides on the hemolytic stability and acetylcholinesterase activity of erythrocytes]. Biull Eksp Biol Med. 1983 Jul;96(7):36-8.

2(0,0,0,2) Details
2379248 Kassa J: [Use of peritoneal dialysis as a therapeutic method in poisoning by Neguvon]. Cesk Farm. 1990 Feb;39(1):7-10.


In experiments on female rats the effect of peritoneal dialysis with variously diluted human plasma in peroral poisoning with the organophosphorous insecticide Neguvon, in which inhibition of blood acetylcholinesterase occurs, was examined.
2(0,0,0,2) Details
16042503 Lotti M, Moretto A: Organophosphate-induced delayed polyneuropathy. . Toxicol Rev. 2005;24(1):37-49.

The ratio of inhibitory powers for acetylcholinesterase and NTE represents the crucial guideline for the aetiological attribution of OP-induced peripheral neuropathy.
In this article, we mainly discuss OP pesticide poisoning, particularly when caused by chlorpyrifos, dichlorvos, isofenphos, methamidophos, mipafox, trichlorfon, trichlornat, phosphamidon/mevinphos and by certain carbamates.
1(0,0,0,1) Details
14727003 Van Kampen M, Selbach K, Schneider R, Schiegel E, Boess F, Schreiber R: AR-R 17779 improves social recognition in rats by activation of nicotinic alpha7 receptors. Psychopharmacology. 2004 Apr;172(4):375-83. Epub 2004 Jan 15.


The SRT and a scopolamine-induced deficit version were validated with the acetylcholinesterase inhibitor metrifonate.
1(0,0,0,1) Details
829002 Benes J, Proksova M, Hrusovsky J: [Treatment with antidotes in sheep perorally intoxicated] . Vet Med. 1976 Dec;21(12):737-46.


A determination of the erythrocytic acetylcholinesterase (AChE, E.C.3.1.1.7.) and plasmatic butyrylcholinesterase (BChE, E.C.3.1.1.8.) activities in the intoxicated sheep should be considered a decisive clinical and diagnostical test for taking veterinary-therapeutical, veterinary-hygienical or veterinary-sanitary measures in intoxications with anti-cholinesterase substances on the whole.
1(0,0,0,1) Details
9383522 Kronforst-Collins MA, Moriearty PL, Schmidt B, Disterhoft JF: Metrifonate improves associative learning and retention in aging rabbits. Behav Neurosci. 1997 Oct;111(5):1031-40.


Metrifonate treatment resulted in steady-state, dose-dependent acetylcholinesterase (AChE) inhibition in red blood cells.
1(0,0,0,1) Details
8107298 Yamanaka S, Yoshida M, Yamamura Y, Nishimura M, Takaesu Y: [A study on acute organophosphorus poisoning--changes in the activity and isoenzyme patterns of serum cholinesterase in human poisoning]. Nippon Eiseigaku Zasshi. 1993 Dec;48(5):955-65.

Fenitrothion, Malathion, Isoxathion, Pyridaphenthion and Trichlorfon, and studied on the changes in the activity and isoenzyme patterns of serum ChE after ingestion.
The main bands in the ChE isoenzyme pattern in normal serum were bands 4 and 5 which had the highest activity of acetylcholinesterase (AChE) with a molecular weight of 600,000-800,000, and bands 7, 12, 14, 17 and 18. 2) Inhibition of serum ChE activity was more severe as the amount ingested increased in patients who took Fenitrothion and Malathion.
1(0,0,0,1) Details
15957009 Lieben CK, Blokland A, Sik A, Sung E, van Nieuwenhuizen P, Schreiber R: The selective 5-HT6 receptor antagonist Ro4368554 restores memory performance in cholinergic and serotonergic models of memory deficiency in the rat. Neuropsychopharmacology. 2005 Dec;30(12):2169-79.


The present study sought to characterize the cognitive-enhancing effects of the 5-HT (6) antagonist Ro4368554 (3-benzenesulfonyl-7-(4-methyl-piperazin-1-yl) 1H-indole) in a rat object recognition task employing a cholinergic (scopolamine pretreatment) and a serotonergic- (tryptophan (TRP) depletion) deficient model, and compared its pattern of action with that of the acetylcholinesterase inhibitor metrifonate.
1(0,0,0,1) Details
1438050 Nordgren I, Karlen B, Kimland M: Metrifonate and tacrine: a comparative study on their effect on acetylcholine dynamics in mouse brain. Pharmacol Toxicol. 1992 Sep;71(3 Pt 1):236-40.


In experimental animals they inhibit acetylcholinesterase activity and have been reported to increase levels of brain acetylcholine.
1(0,0,0,1) Details
2892373 Feldmeier H, Doehring E: Clinical experience with metrifonate. Acta Trop. 1987 Sep;44(3):357-68.


Side effects due to the inhibition of acetylcholinesterase are usually scarce, light and transient in nature.
1(0,0,0,1) Details
8784247 Bassant MH, Jazat-Poindessous F, Lamour Y: Effects of metrifonate, a cholinesterase inhibitor, on local cerebral glucose utilization in young and aged rats. J Cereb Blood Flow Metab. 1996 Sep;16(5):1014-25.


Regional distributions of MFT- and DDVP-induced increases in LCGU were similar and overlapped the distribution of the acetylcholinesterase activity.
1(0,0,0,1) Details
9539412 Becker RE, Colliver JA, Markwell SJ, Moriearty PL, Unni LK, Vicari S: Effects of metrifonate on cognitive decline in Alzheimer disease: a double-blind, placebo-controlled, 6-month study. Alzheimer Dis Assoc Disord. 1998 Mar;12(1):54-7.


The Alzheimer Disease Assessment Scale cognitive subscale score of the metrifonate group treated to a 50-70% inhibition of red blood cell acetylcholinesterase activity differed significantly from the placebo group score by 1.8 points (p < 0.03) due to a deterioration in cognitive performance in the placebo group (p < 0.01).
1(0,0,0,1) Details
235931 Reiner E, Krauthacker B, Simeon V, Skrinjaric-Spoljar M: Mechanism of inhibition in vitro of mammalian acetylcholinesterase and cholinesterase in solutions of 0,0-dimethyl 2,2,2-trichloro-1-hydroxyethyl phosphonate (Trichlorphon). Biochem Pharmacol. 1975 Mar 15;24(6):717-22.

1(0,0,0,1) Details
7344417 Johnson MK: Delayed neurotoxicity - do trichlorphon and/or dichlorvos cause delayed neuropathy in man or in test animals?. Acta Pharmacol Toxicol. 1981;49 Suppl 5:87-98.


In vitro the inhibitory power of dichlorvos against neurotoxic esterase of hen brain is 0.02 x the power against acetylcholinesterase.
1(0,0,0,1) Details
9543466 Jann MW: Preclinical pharmacology of metrifonate. Pharmacotherapy. 1998 Mar-Apr;18(2 Pt 2):55-67; discussion 79-82.


Acetylcholinesterase (AChE) inhibitors, which attempt to prevent the breakdown of ACh, may be classified as short acting, intermediate acting, and long acting based on AChE regeneration time.
2(0,0,0,2) Details
9549662 Pettigrew LC, Bieber F, Lettieri J, Wermeling DP, Schmitt FA, Tikhtman AJ, Ashford JW, Smith CD, Wekstein DR, Markesbery WR, Orazem J, Ruzicka BB, Mas J, Gulanski B: Pharmacokinetics, pharmacodynamics, and safety of metrifonate in patients with Alzheimer's disease. J Clin Pharmacol. 1998 Mar;38(3):236-45.


Metrifonate is converted nonenzymatically to 2.2, dimethyl dichlorovinyl phosphate (DDVP), an inhibitor of acetylcholinesterase (AChE).
2(0,0,0,2) Details
17017223 Cui F, Raymond M, Berthomieu A, Alout H, Weill M, Qiao CL: Recent emergence of insensitive acetylcholinesterase in Chinese populations of the mosquito Culex pipiens (Diptera: Culicidae). J Med Entomol. 2006 Sep;43(5):878-83.

Bioassays performed with a purified G119S strain indicated that this substitution was associated with high levels of resistance to chlorpyrifos, fenitrothion, malathion, and parathion, but low levels of resistance to dichlorvos, trichlorfon, and fenthion.
2(0,0,0,2) Details
9105871 Riekkinen P Jr, Schmidt B, Riekkinen M: Behavioral characterization of metrifonate-improved acquisition of spatial information in medial septum-lesioned rats. Eur J Pharmacol. 1997 Mar 26;323(1):11-9.


We investigated the effects of acute oral pretraining treatment with an indirect acetylcholinesterase inhibitor, metrifonate, on water maze spatial navigation in medial septum-lesioned rats.
1(0,0,0,1) Details
15888665 Quistad GB, Klintenberg R, Casida JE: Blood acylpeptide hydrolase activity is a sensitive marker for exposure to some organophosphate toxicants. Toxicol Sci. 2005 Aug;86(2):291-9. Epub 2005 May 11.

The inhibitory potency of OP pesticides in vivo in mice varies from APH selective (dichlorvos, naled, and trichlorfon), to APH and BChE selective (profenofos and tribufos), to ChE selective or nonselective (many commercial insecticides).
Sarin administered ip at a lethal dose to guinea pigs inhibits blood acetylcholinesterase and BChE completely but erythrocyte APH only partially.
1(0,0,0,1) Details
10584768 Ringman JM, Cummings JL: Metrifonate: update on a new antidementia agent. J Clin Psychiatry. 1999 Nov;60(11):776-82.


The active metabolite of metrifonate, 2,2-dimethyldichlorovinyl phosphate (DDVP), irreversibly inhibits the acetylcholinesterase enzyme.
1(0,0,0,1) Details
8874130 Riekkinen P Jr, Schmidt B, Stefanski R, Kuitunen J, Riekkinen M: Metrifonate improves spatial navigation and avoidance behavior in scopolamine-treated, medial septum-lesioned and aged rats. Eur J Pharmacol. 1996 Aug 8;309(2):121-30.


We investigated the effects of acute p.o. pretraining treatment with an indirect acetylcholinesterase inhibitor, metrifonate, on water maze spatial navigation and passive avoidance behavior.
1(0,0,0,1) Details
9758555 Oberpichler-Schwenk H: [Alzheimer disease. Med Monatsschr Pharm. 1998 Aug;21(8):250.


Irreversible AChE inhibition with metrifonate]
1(0,0,0,1) Details
11822883 Liu L, Ikonen S, Heikkinen T, Tapiola T, van Groen T, Tanila H: The effects of long-term treatment with metrifonate, a cholinesterase inhibitor, on cholinergic activity, amyloid pathology, and cognitive function in APP and PS1 doubly transgenic mice. Exp Neurol. 2002 Feb;173(2):196-204.


To investigate whether acetylcholinesterase inhibitors (ChEIs) could decrease production of amyloid beta-peptide (A (beta)) and slow down the accumulation of A (beta) also in vivo, we chronically administered metrifonate (100 mg/kg, po), a second-generation ChEI, to 7-month-old doubly transgenic APP+PS1 mice and their nontransgenic littermate controls for 7 months.
2(0,0,0,2) Details
9720485 Tariot PN: Evaluating response to metrifonate. J Clin Psychiatry. 1998;59 Suppl 9:33-7.


Metrifonate, administered orally to patients with probable Alzheimer's disease in a once-daily dose, readily enters the brain and inhibits brain acetylcholinesterase (AChE) activity in a dose-dependent fashion.
2(0,0,0,2) Details
11558939 Pakaski M, Papp H, Rakonczay Z, Fakla I, Kasa P: Effects of acetylcholinesterase inhibitors on the metabolism of amyloid precursor protein in vitro. Neurobiology. 2001;9(1):55-7.

1(0,0,0,1) Details
10733052 Shikiar R, Shakespeare A, Sagnier PP, Wilkinson D, McKeith I, Dartigues JF, Dubois B: The impact of metrifonate therapy on caregivers of patients with Alzheimer's disease: results from the MALT clinical trial. J Am Geriatr Soc. 2000 Mar;48(3):268-74.


CONCLUSIONS: This study provides the first evidence from a randomized clinical trial of any acetylcholinesterase inhibitor used in the treatment of AD demonstrating a positive impact on the patient's caregiver as well as benefits to the patient.
1(0,0,0,1) Details
11311445 Rakonczay Z, Papp H: Effects of chronic metrifonate treatment on cholinergic enzymes and the blood-brain barrier. Neurochem Int. 2001 Jul;39(1):19-24.


In vitro, metrifonate proved to be a more potent inhibitor of butyryl- than of acetylcholinesterase in both the cortex and the hippocampus.
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1288683 Anishchenko TG, Mamontov BN, Shorina LN: [Sex differences in the cholinergic status of white rats] . Biull Eksp Biol Med. 1992 Oct;114(10):351-3.


Female rats injected with organophosphate inhibitor of acetylcholinesterase chlorophose at doses of 10 mg/kg and 360 mg/kg showed less considerable decrease in blood acetylcholinesterase activity than did male animals.
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10395091 Ikonen S, Schmidt BH, Riekkinen P Jr: Characterization of learning and memory behaviors and the effects of metrifonate in the C57BL strain of mice. Eur J Pharmacol. 1999 May 14;372(2):117-26.


These experiments were complemented by an investigation of the effects of acute treatment with an acetylcholinesterase inhibitor, metrifonate, in these behavioral tests.
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718420 Nordgren I, Bergstrom M, Holmstedt B, Sandoz M: Transformation and action of metrifonate. Arch Toxicol. 1978 Oct 13;41(1):31-41.


The effect of metrifonate and dichlorvos on acetylcholine levels, acetylcholinesterase activity and synthesis rate of acetylcholine in mouse brain was also studied.
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9726626 Giovannini MG, Scali C, Bartolini L, Schmidt B, Pepeu G: Effect of subchronic treatment with metrifonate and tacrine on brain cholinergic function in aged F344 rats. Eur J Pharmacol. 1998 Jul 31;354(1):17-24.


The effects of 21-day treatment with the acetylcholinesterase inhibitors metrifonate (80 mg kg (-1) per os (p.o.)) and tacrine (3 mg kg (-1) p.o.), twice daily, on cortical and hippocampal cholinergic systems were investigated in aged rats (24-26 months).
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9718228 McKeith IG: The clinical trial protocol of the Metrifonate in Alzheimer's Trial (MALT). Dement Geriatr Cogn Disord. 1998;9 Suppl 2:2-7.


The promising results of early trials in Alzheimer's disease with the acetylcholinesterase inhibitor metrifonate prompted initiation of the Metrifonate in ALzheimer's Trial (MALT).
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12093157 Liste I, Bernard V, Bloch B: Acute and chronic acetylcholinesterase inhibition regulates in vivo the localization and abundance of muscarinic receptors m2 and m4 at the cell surface and in the cytoplasm of striatal neurons. Mol Cell Neurosci. 2002 Jun;20(2):244-56.

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8231460 Moriearty PL, Thornton SL, Becker RE: Transdermal patch delivery of acetylcholinesterase inhibitors. . Methods Find Exp Clin Pharmacol. 1993 Jul-Aug;15(6):407-12.

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10599773 Farlow MR, Cyrus PA, Nadel A, Lahiri DK, Brashear A, Gulanski B: Metrifonate treatment of AD: influence of APOE genotype. Neurology. 1999 Dec 10;53(9):2010-6.


BACKGROUND: Metrifonate is a new acetylcholinesterase inhibitor for the treatment of AD symptoms.
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11106308 Dronfield S, Egan K, Marsden CA, Green AR: Comparison of donepezil-, tacrine-, rivastigmine- and metrifonate-induced central and peripheral cholinergically mediated responses in the rat. J Psychopharmacol. 2000;14(3):275-9.


The data are consistent with clinical results and indicate that simple in-vivo models may assist in the selection of acetylcholinesterase inhibitors with a suitable response profile for use in the symptomatic treatment of Alzheimer's disease.
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9595967 Morris JC, Cyrus PA, Orazem J, Mas J, Bieber F, Ruzicka BB, Gulanski B: Metrifonate benefits cognitive, behavioral, and global function in patients with Alzheimer's disease. Neurology. 1998 May;50(5):1222-30.


OBJECTIVE: To evaluate the efficacy and safety of metrifonate, an acetylcholinesterase inhibitor, in patients clinically diagnosed with probable Alzheimer's disease (AD) of mild to moderate severity.
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9595966 Cummings JL, Cyrus PA, Bieber F, Mas J, Orazem J, Gulanski B: Metrifonate treatment of the cognitive deficits of Alzheimer's disease. Neurology. 1998 May;50(5):1214-21.


The efficacy and safety of metrifonate, an acetylcholinesterase inhibitor, was evaluated clinically in patients diagnosed with mild to moderate Alzheimer's disease (AD).
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2955651 Wang GF, Zheng H, Huang ZY: [Schistosomicides and acetylcholinesterase in the tegument of the male Schistosoma japonicum] Zhongguo Yao Li Xue Bao. 1986 Nov;7(6):567-9.

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10362441 Raskind MA, Cyrus PA, Ruzicka BB, Gulanski BI: The effects of metrifonate on the cognitive, behavioral, and functional performance of Alzheimer's disease patients. J Clin Psychiatry. 1999 May;60(5):318-25.


BACKGROUND: The objective of this study was to evaluate the efficacy and safety of metrifonate, a long-acting acetylcholinesterase inhibitor, in patients clinically diagnosed with probable Alzheimer's disease of mild-to-moderate severity.
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11193171 Giacobini E: Cholinesterase inhibitors stabilize Alzheimer's disease. Ann N Y Acad Sci. 2000;920:321-7.


In order to explain the stabilizing effect of ChEI, a mechanism other than AChE inhibition, based on beta-amyloid metabolism, is postulated.
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1115426 Silvestri R, Himes JA, Edds GT: Repeated oral administration of coumaphos in sheep: effects on erythrocyte acetylcholinesterase and other constituents. Am J Vet Res. 1975 Mar;36(3):283-7.

Treatment of sheep with an intravenous injection of the organophosphorous compound trichlorfon, insufficient to produce a significant effect on erythrocyte cholinesterase activity, produced additive effects with those of coumaphos.
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10753002 Gelinas I, Gauthier S, Cyrus PA: Metrifonate enhances the ability of Alzheimer's disease patients to initiate, organize, and execute instrumental and basic activities of daily living. J Geriatr Psychiatry Neurol. 2000 Spring;13(1):9-16.


The objective of this analysis was to evaluate comprehensively the efficacy of metrifonate, a long-acting acetylcholinesterase inhibitor, in improving the ability of mild-to-moderate Alzheimer's disease (AD) patients to perform activities of daily living (ADLs).
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10509429 Abdelsalam EB: Neurotoxic potential of six organophosphorus compounds in adult hens. Vet Hum Toxicol. 1999 Oct;41(5):290-2.

The neurotoxic potential of trichlorfon, diazinon, phosmet, dichlorvos, phosphamidon and coumaphos was evaluated for their ability to inhibit brain neurotoxic esterase (NTE) activity in adult hens.
All compounds were administered at high single oral doses and the NTE and acetylcholinesterase (AchE) activities were measured at 24 h and 6 w later.
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1945043 Hosono R, Kamiya Y: Additional genes which result in an elevation of acetylcholine levels by mutations in Caenorhabditis elegans. Neurosci Lett. 1991 Jul 22;128(2):243-4.


In addition to the abnormal accumulation of ACh, mutants in these 7 genes possess common phenotypes in locomotion, resistance to inhibitors of acetylcholinesterase (AChE) and in post-embryonic development.
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11590700 Yavo B, Brunetti IL, da Fonseca LM, Catalani LH, Campa A: Selective activity of butyrylcholinesterase in serum by a chemiluminescent assay. Luminescence. 2001 Sep-Oct;16(5):299-304.


Addition of aliesterase inhibitors, such as fluoride ion and trichlorfon or the cholinesterase inhibitor eserine, totally prevents light emission.
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1914997 Dunier M, Siwicki AK, Demael A: Effects of organophosphorus insecticides: effects of trichlorfon and dichlorvos on the immune response of carp (Cyprinus carpio). Ecotoxicol Environ Saf. 1991 Aug;22(1):79-87.

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10743648 Gimenez-Pardo C, Ros Moreno RM, De Armas-Serra C, Rodriguez-Caabeiro F: Presence of cholinesterases in Echinococcus granulosus protoscolices. Parasite. 2000 Mar;7(1):47-50.


To characterize these activities as acetylcholinesterases or pseudocholinesterases, BW284C51 and the organophosphate anthelmintic Neguvon were assayed as specific inhibitors of acetylcholinesterases, while Iso-OMPA was employed as specific inhibitor of pseudocholinesterases.
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12654229 Hou Y, Fu F, Liu S, Liu C, Sun Y, Qiu S: [The profiles of free organophosphorus poisons in the bile of rabbits poisoned with different organophosphates]. Zhonghua Nei Ke Za Zhi. 2002 Dec;41(12):795-7.

METHODS: Seventy two livid blue rabbits, male, 2 - 2.5 kg in weight, were divided into 3 groups: trichlorfon (556.0 mg/kg), monocrotophos (11.12 mg/kg) and methyl parathion (37.05 mg/kg).
Acetylcholinesterase (AChE) activity was measured with dithiobisnitrobenzoic acid (DTNB) enzyme kinetic method.
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2311566 Cossarini-Dunier M, Demael A, Siwicki AK: In vivo effect of the organophosphorus insecticide trichlorphon on the immune response of carp (Cyprinus carpio). Ecotoxicol Environ Saf. 1990 Feb;19(1):93-8.


Contamination of organs was analyzed by acetylcholinesterase activity.
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10556869 Dubois B, McKeith I, Orgogozo JM, Collins O, Meulien D: A multicentre, randomized, double-blind, placebo-controlled study to evaluate the efficacy, tolerability and safety of two doses of metrifonate in patients with mild-to-moderate Alzheimer's disease: the MALT study. Int J Geriatr Psychiatry. 1999 Nov;14(11):973-82.


BACKGROUND: Metrifonate is a long-lasting acetylcholinesterase inhibitor being developed for the symptomatic treatment of Alzheimer's disease (AD).
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3840091 Tomlinson G, Albuquerque CA, Woods RA: The effects of amidantel (BAY d 8815) and its deacylated derivative (BAY d 9216) on Caenorhabditis elegans. Eur J Pharmacol. 1985 Jul 17;113(2):255-62.


The drugs were moderately potent inhibitors of both E. electricus and C. elegans acetylcholinesterase but at concentrations too high to account for their abilities to contract cut worms.
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