The effect of different histamine H2-receptor antagonists on the gastric acid secretion of the isolated whole stomach of the mouse and on the heart rate of spontaneously beating atrium of the guinea-pig.

The effect of metiamide, cimetidine and 2-[2-[5-(dimethylaminomethyl)furan-2-ylmethylthio]ethylamino]- 5-(6-methylpyrid-3-ylmethyl)-pyrimidin-4-one (SK & F 93 479) was studied on the acid secretion of the isolated stomach of the mouse and on the heart rate of the right atrium of the guinea-pig. The order of potency of histamine H2-antagonists investigated was identical on atrium and stomach, however, the pA2 values obtained on acid secretion were approximately 10 times lower than those found on atrium.