Stimulation of insulin secretion by beta-endorphins (1-27 & 1-31).
Synthetic human beta-endorphin potentiates insulin secretion by the isolated perfused rat pancreas when glucose is present in the perfusate at concentrations of either 125 or 200 mg/dl, whereas it fails to exert any effect on insulin secretion in the presence of a substimulatory concentration of 100 mg/dl. Similar potentiation of insulin secretion occurred in response to the 1-27 fragment (beta-endorphin1-27) of beta-endorphin. This transient potentiation lasts only 3 to 4 minutes, whereupon secretion returns toward control levels. Thus beta-endorphin produces only a transient spike-like secretory profile similar to the first phase of glucose-induced insulin secretion and it fails to produce any chronic insulin secretory response comparable to the second phase of insulin secretion. The insulinotropic effect of beta-endorphins occurred at concentrations varying from 0.1 to 5.0 ug/ml. These data suggest that beta-endorphin and beta-endorphin1-27 potentiate insulin secretion via a common beta cell opioid receptor, and that beta-endorphin may exert a paracrine control of insulin secretion. However, any such regulation appears to be via short-term alterations in the secretory process per se.
D000818:Animals; D004723:Endorphins / Q000138:chemical synthesis / Q000494:pharmacology*; D005215:Fasting; D005947:Glucose / Q000008:administration & dosage / Q000502:physiology; D006801:Humans; D066298:In Vitro Techniques; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D010446:Peptide Fragments / Q000138:chemical synthesis / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D011956:Receptors, Cell Surface / Q000187:drug effects; D013997:Time Factors; D001615:beta-Endorphin
D004723:Endorphins; D007328:Insulin; D010446:Peptide Fragments; D011956:Receptors, Cell Surface; D001615:beta-Endorphin; C035581:beta-endorphin (1-27); D005947:Glucose