| 11495692 |
Yoshida M, Yoshida H, Kitaichi K, Hiramatsu K, Kimura T, Ito Y, Kume H, Yamaki K, Suzuki R, Shibata E, Hasegawa T, Takagi K: Adrenomedullin and proadrenomedullin N-terminal 20 peptide induce histamine release from rat peritoneal mast cell. Regul Pept. 2001 Sep 15;101(1-3):163-8.
Adrenomedullin (ADM)-induced histamine release from rat peritoneal mast cells was investigated. We compared the ability of full-length ADM to induce histamine release to the fragments ADM-(1-25) and ADM-(22-52), as well as proadrenomedullin N-terminal 20 peptide (PAMP). ADM (10 (-8) to 10 (-5) M) and PAMP (10 (-8) to 10 (-5) M) dose-dependently increased histamine release from peritoneal mast cell preparations. The effect of ADM-(1-25) was similar to ADM, whereas ADM-(22-52) did not show any effects. These data suggest the relative importance of the ADM C-terminal fragment, which contains a six-membered ring structure. Histamine release, induced by ADM, was significantly and dose-dependently inhibited by the addition of ADM-(22-52) (10 (-5) M), Ca (2+) (0.5 to 2.0 mM), and benzalkonium chloride (3 to 7 microM), a selective inhibitor of Gi type G proteins. In contrast, PAMP (10 (-5) M)-induced histamine release was not inhibited by Ca (2+). These results suggest that ADM induce histamine release via a putative ADM receptor in a manner sensitive to Gi-protein function and extracellular Ca (2+) concentration, and that PAMP might produce its effect by a different mechanism than ADM. |
81(1,1,1,1) |