Role of endogenous calcitonin in the secretion of gastrin and gastric acid in rats.

Following pyloric ligation, serum immunoreactive gastrin levels and gastric acid accumulation in acutely thyroidectomized rats with autotransplanted parathyroid glands were significantly higher than those in thyroid intact rats. Furthermore, serum immunoreactive gastrin levels were higher in the absence than in the presence of the thyroid gland following the oral administration of glycine or rat chaw. These results suggest that endogeneous calcitonin has an inhibitory action on gastric acid secretion probably through the inhibitory action on gastrin secretion in rats.