Kinetics of somatostatin inhibition of pentagastrin-stimualted gastric acid secretion.
Dogs with gastric fistulae and denervated gastric pouches received graded doses of pentagastrin with and without a background infusion of somatostatin (1 microgram kg-1 h-1). Similarly, graded doses of somatostatin (0.25, 0.5, 1, 2 and 4 microgram kg-1 h-1) were infused after a steady state gastric secretion had been achieved with pentagastrin (1.5 microgram kg-1 h-1), about twice the dose required to produce half maximal (D50) response. Somatostatin inhibited pentagastrin-stimulated gastric acid secretion with competitive inhibition kinetics, but its precise site of action remains uncertain. The minimum effective dose of somatostatin on a twice D50 dose of pentagastrin was 0.25 microgram kg-1 h-1.
D000818:Animals; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D005750:Gastric Juice / Q000187:drug effects / Q000378:metabolism*; D007700:Kinetics; D010418:Pentagastrin / Q000037:antagonists & inhibitors*; D013004:Somatostatin / Q000494:pharmacology*
D013004:Somatostatin; D010418:Pentagastrin