Salivary peptide P-C potentiates insulin release and inhibits glucagon release from isolated perfused pancreas of the diabetic GK rat.
We investigated the effects of the salivary peptide P-C (P-C), a saliva-derived peptide, on glucose (8.3 mM)- and arginine (10 mM)-induced insulin release and arginine (10 mM)-induced glucagon release using the perfused pancreas of spontaneously diabetic GK rats. Both its potentiating effect on insulin release and its inhibitory effect on glucagon release were concentration-dependent in diabetic GK rats. The ratio of insulin release obtained with P-C (194 nM) to that without P-C in GK rats was the same as ratio in normal Wistar rats. The ratio (0.40) of glucagon release obtained with P-C (194 nM) to that without P-C was smaller in diabetic GK rats than that (0.75) in normal Wistar rats. These results indicate that P-C inhibits arginine-induced glucagon release in diabetic GK rat pancreas more effectively than in normal Wistar rat pancreas.
Nakashima
N
N
Department of Chemical Pharmacology, Faculty of Pharmaceutical Sciences, Toyama Medical and Pharmaceutical University, Japan.
Kimura
I
I
Kimura
M
M
D000818:Animals; D001120:Arginine / Q000494:pharmacology; D003921:Diabetes Mellitus, Experimental; D005934:Glucagon / Q000378:metabolism*; D007150:Immunohistochemistry; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D008297:Male; D010179:Pancreas / Q000378:metabolism*; D010455:Peptides / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar
D007328:Insulin; D010455:Peptides; D005934:Glucagon; D001120:Arginine