THE EFFECTS OF 2 FMRFAMIDE RELATED PEPTIDES (A-18-F-AMIDE AND F-8-F-AMIDE - MORPHINE MODULATING PEPTIDES) ON THE ENDOCRINE AND EXOCRINE RAT PANCREAS

The effects of two recently isolated mammalian FMRFamide related peptides (A-18-F-amide and F-8-F-amide) on the encocrine and exocrine rat pancreas were investigated. A-18-F-amide (10, 100, 1000 pM) inhibited concentration dependently glucose (10 mM)- and arginine (10 mM)-induced insulin secretion from the isolated perfused rat pancreas during the first (controls: 100%; 10 pM: 114%; 100 pM: 63%, p < 0.05; 1000 pM: 31%, p < 0.05) and the second secretion phase (controls: 100%; 10 pM: 102%; 100 pM: 78%; 1000 pM: 27%, p < 0.05). The inhibitory actions of A-18-F-amide on pancreatic D-cell secretion were more pronounced during the first than the second phase (first phase: controls: 100%; 10 pM: 95%; 100 pM: 37%, p < 0.05; 1000 pM: 39%, p < 0.05%; second phase: controls: 100%; 10 pM: 113%; 100 pM: 72%; 1000 pM: 59%, p < 0.05). F-8-F-amide (at 1000 pM) inhibited stimulated insulin (controls: 100%; first phase: 26%, p < 0.05%; second phase: 20%, p < 0.05) and somatostatin release (controls: 100%; first phase: 14%, p < 0.05; second phase: 29%, p < 0.05). Both peptides were without effect on basal and CCK-8-stimulated amylase release from isolated incubated rat pancreatic acini. © 1990.