Effect of pertussis toxin on A1-receptor-mediated inhibition of insulin secretion.
Previous studies have provided evidence for the presence on B cell membrane of adenosine receptors (P1-purinoceptors) of the A1-subtype which inhibit insulin secretion. In this work we have investigated the implication of a guanosine triphosphate (GTP) binding protein (G protein) in the A1 purinoceptor-induced inhibition of insulin secretion from the isolated perfused pancreas of the rat. A group of rats was treated with pertussis toxin (10 micrograms kg-1, i.v.) 28 h prior to pancreas extirpation. This treatment totally abolished the 50% decrease in insulin secretion induced by (+)-N6-phenylisopropyl adenosine (1.65 microM), a P1-purinoceptor agonist. These results indicate that the A1-receptor-mediated inhibition of insulin secretion involves a pertussis toxin-sensitive G protein.
Hillaire-Buys
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Faculté de Médecine, UA 599 du CNRS, Institut de Biologie, Montpellier, France.
Gross
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Loubatières-Mariani
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MM
Ribes
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G
D000818:Animals; D019204:GTP-Binding Proteins / Q000502:physiology; D066298:In Vitro Techniques; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D008297:Male; D010179:Pancreas / Q000378:metabolism; D037342:Pertussis Toxin; D010660:Phenylisopropyladenosine / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D011983:Receptors, Purinergic / Q000187:drug effects* / Q000502:physiology; D010566:Virulence Factors, Bordetella / Q000494:pharmacology*
D007328:Insulin; D011983:Receptors, Purinergic; D010566:Virulence Factors, Bordetella; D010660:Phenylisopropyladenosine; D037342:Pertussis Toxin; D019204:GTP-Binding Proteins