Dual Alpha2C/5HT1A Receptor Agonist Allyphenyline Induces Gastroprotection and Inhibits Fundic and Colonic Contractility
The intracerebroventricularly (i.c.v.) injected presynaptic alpha2-adrenoceptor agonists, clonidine and oxymetazoline, exerted a dose-dependent inhibition on the gastric acid secretion in pylorus-ligated rats; the ED50 values were 20 and 7.5 nmol/rat, respectively. Moreover, beta-endorphin, given i.c.v., also decreased acid secretion (ED50=0.25 nmol/rat i.c.v.). The antisecretory effect of these compounds was highly reduced by glibenclamide (10 nmol/rat i.c.v.), a selective blocker of K(ATP) channels. These results suggest that K(ATP) channels in the central nervous system are likely to be involved in the centrally initiated antisecretory action of both alpha2-adrenoceptor agonists and beta-endorphin.