title: Comparative effect of somatostatin-14 and somatostatin-28 on glucagon-induced glycogenolysis from the perfused rat liver.
abstract: The effect of somatostatin (SS)-14 and SS-28 on glycogenolysis was studied, using a rat liver perfusion technique. Livers from nonfasted rats were perfused with 5.5 mmol/L glucose or perfusate without the glucose addition. Glucagon-induced glucose output was lower in the presence of 5.5 mmol/L glucose than in glucose free perfusate at every concentration of glucagon. Under glucose free conditions, SS-14 given at five minutes prior to the glucagon addition reduced the glucagon-induced glucose output dose-dependently. SS-14 given 15 minutes after glucagon addition also inhibited glucagon-induced glucose output significantly. However, various concentrations of SS-28 failed to affect glucose output. On the other hand, in the presence of 5.5 mmol/L glucose, neither SS-14 nor SS-28 affected glucagon-induced glucose output. It is suggested, therefore, that glycogenolysis induced by glucagon from the liver is reduced by SS-14, but not by SS-28, only under glucose free conditions.
mesh_terms: D000818:Animals; D005934:Glucagon / Q000494:pharmacology*; D008112:Liver Glycogen / Q000378:metabolism*; D008297:Male; D010477:Perfusion; D051381:Rats; D011919:Rats, Inbred Strains; D013004:Somatostatin / Q000494:pharmacology*; D053561:Somatostatin-28; D013552:Swine
chemical_list: D008112:Liver Glycogen; D013004:Somatostatin; D053561:Somatostatin-28; D005934:Glucagon