Effect of pertussis toxin on hormonal responsiveness of rat hepatocytes.
The ureogenic action of epinephrine in hepatocytes from normal adult rats is mediated through activation of alpha 1-adrenoceptors. beta-Adrenoceptors in addition to alpha 1-adrenoceptors, became involved in mediating this effect in cells from animals treated with pertussis toxin. The accumulation of cyclic-AMP in response to epinephrine or isoproterenol was markedly increased in hepatocytes from pertussis-treated rats as compared to that observed in control cells. The accumulation of cyclic-AMP due to glucagon was also increased. It is suggested that pertussis toxin may release a constraint on adenylate cyclase activity by blocking the inhibitory coupling mechanism (Ni) or some other entity involved in the regulation of the activity of this enzyme.
D037361:Adenylate Cyclase Toxin; D000818:Animals; D001427:Bacterial Toxins / Q000494:pharmacology*; D000242:Cyclic AMP / Q000378:metabolism; D004837:Epinephrine / Q000494:pharmacology*; D005260:Female; D005934:Glucagon / Q000494:pharmacology*; D066298:In Vitro Techniques; D007545:Isoproterenol / Q000494:pharmacology*; D007700:Kinetics; D008099:Liver / Q000187:drug effects / Q000378:metabolism*; D037342:Pertussis Toxin; D010716:Phosphatidylinositols / Q000096:biosynthesis; D011224:Prazosin / Q000494:pharmacology*; D011799:Quinazolines / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D014508:Urea / Q000378:metabolism*; D010566:Virulence Factors, Bordetella
D037361:Adenylate Cyclase Toxin; D001427:Bacterial Toxins; D010716:Phosphatidylinositols; D011799:Quinazolines; D010566:Virulence Factors, Bordetella; D014508:Urea; D005934:Glucagon; D000242:Cyclic AMP; D037342:Pertussis Toxin; D007545:Isoproterenol; D011224:Prazosin; D004837:Epinephrine