Effects of carbachol and gastrin on 14C-aminopyrine accumulated in rabbit gastric glands and cells.

The present study examines the possible existence of a mechanism regulating emptying of the secretory canaliculi content of the parietal cell and the possible effects of carbachol and gastrin on such a mechanism. In rabbit gastric glands stimulated with carbachol, 14C-aminopyrine accumulation reached a maximum after 15 min and then started to decrease. This decrease was not accompanied by a decrease in oxygen consumption, nor was any decrease of accumulated 14C-aminopyrine seen in dispersed gastric cells. In glands but not in cells stimulated with histamine together with 3-isobutyl-1-methylxanthine (IMX), carbachol induced a reduction in the accumulated 14C-aminopyrine content, whereas the effect of gastrin was less pronounced. The carbachol-induced reduction was counteracted by atropine but was not accompanied by a decrease in oxygen consumption. It is suggested that there exists a mechanism that controls the emptying of the secretory canaliculi content of the parietal cell, and that carbachol, in addition to stimulating acid production, also contributes to this emptying. Paracrine factors may be involved in this latter mechanism.