The essential amino acid domains in salivary peptide P-C that potentiate glucose-induced insulin release and inhibit arginine-induced glucagon release from perfused rat pancreas.
The amino acid domains in salivary peptide P-C (1-44 peptide fragments, P-C) that are essential to potentiate insulin release and inhibit glucagon release were investigated using isolated perfused rat pancreas. P-C significantly potentiated not only glucose (8.3 mM)-induced insulin release, but also arginine (10 mM)-induced insulin release. The essential domain responsible for potentiation of insulin release was the P-C-(23-29) fragment, 23KPQGPPP29, while that inhibiting glucagon release was the P-C-(12-18) fragment, 12HQQGPPP18. Since both domains share a common fragment, QGPP, these findings indicate that the functional amino acid sequences KP and HQ may potentiate insulin release and inhibit glucagon release, respectively.
Kimura
M
M
Department of Chemical Pharmacology, Faculty of Pharmaceutical Sciences, Toyama Medical and Pharmaceutical University, Japan.
Nakashima
N
N
Kimura
I
I
D000596:Amino Acids / Q000737:chemistry; D000818:Animals; D001120:Arginine / Q000494:pharmacology; D005934:Glucagon / Q000378:metabolism*; D007150:Immunohistochemistry; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D008297:Male; D010179:Pancreas / Q000502:physiology*; D010455:Peptides / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar
D000596:Amino Acids; D007328:Insulin; D010455:Peptides; D005934:Glucagon; D001120:Arginine