Sex hormones, and acid gastric secretion induced with carbachol, histamine, and gastrin.

This study confirms previous reports that satisfactory gastric acid secretory responses to intravenous administration of histamine, carbachol, and gastrin can be obtained. Bilateral castration of the male rats significantly reduced acid gastric secretory responses to carbachol but not to histamine. Overiectomized rats treated with 17B-oestradiol (short-term treatment) showed a statistically significant reduction in gastric acid secretion induced with all the secretagogues, but the results when rats were treated with testosterone were inconsistent. In animals given gastrin or histamine gastric acid secretion was reduced and was of statistical significance with gastrin (0.02 < p < 0.05) but not with histamine (0.05 < p > 0.1). It is concluded that a high oestrogen blood level is capable of inhibiting effectively acid gastric secretion in both sexes except that a higher level of blood oestrogen is required in the male. The results showed further that of all the sex hormones used, only oestrogen had a significant effect on gastric acid secretion.