Human pharmacological effects of SMS 201-995 on gastric secretion.

The inhibition of pentagastrin-stimulated-(3 micrograms kg-1 h-1) gastric acid secretion by various doses of intravenous and subcutaneous SMS 201-995, a somatostatin analogue, was investigated in healthy volunteers by means of gastric aspiration, using phenol red as a volume marker. The intravenous doses were compared with the standard dose of somatostatin-14, 3.5 micrograms kg-1 h-1. Similarly, SMS 201-995-induced inhibition of gastric acid secretion was compared with that of exocrine pancreatic secretion assessed by gastroduodenal aspiration. The results can be summarized as follows: SMS 201-995 is a potent inhibitor of gastric acid secretion, exerting near maximal inhibition at a dose of greater than or equal to 0.56 micrograms kg-1 h-1. Near maximal inhibition equals that achieved with SST-14 (3.5 micrograms kg-1 h-1). Pancreatic enzyme secretion appears to be strongly inhibited by lower doses of SMS 201-995 than gastric secretion. Single subcutaneous injections of SMS 201-995 produce an inhibition of gastric acid secretion lasting for many hours. Near maximal inhibition was obtained with a dose of 100 micrograms.