The adenyl cyclase present in rabbit gastric mucosa is stimulated by histamine and fluoride when derived from the fundic area, but from the antral area histamine does not affect the activity of the enzyme. Burimamide inhibits the histamine stimulated component as does Mn++. Of the various histamine analogs tested, those which stimulate adenyl cyclase also stimulate secretion. Guanyl cyclase activity is not affected by any of the hormones tested, and antrum has a higher specific activity than fundus.
