Part I Inhibition of canine gastric secretion by compound SC 15396 given orally and parenterally

A new compound, 2-phenyl-2-(2-pyridyl) thioacetamide (Fig. 1) with a powerful inhibitory effect on gastric secretion has recently been synthesised.' Bedi, Gillespie, and Gillespie (1967), using vagally innervated and Heidenhain pouch dogs, have shown it to inhibit gastrin-stimulated acid secretion. In that they failed to demonstrate any effect on histaminestimulated or amechol-stimulated gastric secretion, they claim that it is a specific gastrin antagonist. The compound has a molecular weight of 228-3 and melting point of 133 to 141°C. It is almost insoluble in water, sparingly soluble in petroleum ether, ethanol and propylene glycol, but readily soluble in chloroform and acetone or dimethyl sulphoxide. In preliminary testing it has been shown to have a low acute and chronic toxicity in rats and dogs. Because of its theoretical and practical potential, we have assessed its effect on gastric secretion stimulated in various ways. The three papers presented here report work undertaken independently, N