AJP - Gastrointestinal and Liver Physiology, Vol 268, Issue 6 889-G894, Copyright © 1995 by American Physiological Society

ARTICLES

Platelet-activating factor stimulates gastric acid secretion in isolated rabbit gastric glands

I. Sobhani, A. Bado, L. Moizo, J. P. Laigneau, T. Tarrade, P. Braquet and M. J. Lewin
Unite de Recherche de Gastroenterologie, Institut National de la Sante et de la Recherche Medicale Unite 10, Hopital Bichat, Paris. France.

We examined the effect of platelet-activating factor (PAF) on gastric acid secretion by isolated rabbit gastric glands as determined by [14C]aminopyrine ([14C]AP) uptake. PAF, histamine, and carbachol time- and concentration-dependently stimulated [14C]AP uptake, with estimated half-maximal effective concentrations of 60 pM, 0.25 microM, and 0.1 microM, respectively. PAF-induced [14C]AP uptake was inhibited by the specific PAF antagonists BN-50727 and SR-27417 and by the proton pump inhibitors omeprazole and lansoprazole. However, the H2-receptor antagonist famotidine had no effect. Buffering extracellular Ca2+ by ethylene glycol-bis(beta-amino-ethyl ether)-N,N,N',N'-tetraacetic acid resulted in a shift to the right of the time-course effect of PAF without altering the maximal response, whereas buffering intracellular Ca2+ by 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid 2-acetoxymethyl ester, as well as blocking Ca2+ channels by verapamil, inhibited PAF-induced [14C]AP uptake. Intracellular Ca2+ concentration in isolated rabbit gastric glands, as measured by fura 2-acetoxymethyl ester, concentration-dependently increased in response to PAF, to a maximum of 1.5-fold for 0.1 microM. These results suggest that PAF stimulates gastric acid secretion via specific receptors activating intracellular Ca2+ mobilization, which could be located on the parietal cells.

This article has been cited by other articles:

				I. Sobhani, S. Canedo, B. Alchepo, C. Vissuzaine, C. Chevalier, M. Buyse, L. Moizo, J. P. Laigneau, M. Mignon, J. M. Lewin, et al. Putative effect of Helicobacter pylori and gastritis on gastric acid secretion in cat Am J Physiol Gastrointest Liver Physiol, April 1, 2002; 282(4): G727 - G734. [Abstract] [Full Text] [PDF]

				I L P Beales and J Calam Interleukin 1beta and tumour necrosis factor alpha  inhibit acid secretion in cultured rabbit parietal cells by multiple pathways Gut, February 1, 1998; 42(2): 227 - 234. [Abstract] [Full Text] [PDF]