Homologous beta-adrenergic desensitization in isolated rat hepatocytes.
Hepatocytes from hypothyroid rats have a marked beta-adrenergic responsiveness. Preincubation of these hepatocytes with isoprenaline induced a time-dependent and concentration-dependent desensitization of the beta-adrenergic responsiveness without altering that to glucagon (homologous desensitization). The desensitization was evidenced both in the cyclic AMP accumulation and in the stimulation of ureagenesis induced by the beta-adrenergic agonists. Under the same conditions, preincubation with glucagon induced no desensitization. Propranolol was also unable to induce desensitization, but blocked that induced by isoprenaline. Pertussis-toxin treatment did not alter the homologous beta-adrenergic desensitization induced by isoprenaline.
García-Sáinz
J A
JA
Departamento de Bioenergética, Universidad Nacional Autónoma de México, D.F.
Michel
B
B
D000818:Animals; D000242:Cyclic AMP / Q000378:metabolism; D005260:Female; D005934:Glucagon / Q000378:metabolism / Q000494:pharmacology; D007037:Hypothyroidism / Q000378:metabolism; D066298:In Vitro Techniques; D007545:Isoproterenol / Q000494:pharmacology*; D008099:Liver / Q000187:drug effects / Q000378:metabolism*; D037342:Pertussis Toxin; D051381:Rats; D011919:Rats, Inbred Strains; D014508:Urea / Q000096:biosynthesis; D010566:Virulence Factors, Bordetella / Q000494:pharmacology
D010566:Virulence Factors, Bordetella; D014508:Urea; D005934:Glucagon; D000242:Cyclic AMP; D037342:Pertussis Toxin; D007545:Isoproterenol