Identification of beta-adrenergic sensitive adenylate cyclase in rat thoracic duct.
The effect of L-isoproterenol on the 3',5'-cyclic adenosine monophosphate (cAMP) generating system in rat thoracic duct membranes was investigated in order to identify beta-adrenergic receptors. L-Isoproterenol elicited a dose-dependent stimulation of cAMP formation; L-noradrenaline was less effective than L-isoproterenol in stimulating cAMP increase, whereas L-phenylephrine was without important effects on cAMP levels. L-Propranolol, a selective antagonist of beta-adrenergic receptors, caused a dose-dependent decrease of the effects of L-isoproterenol. In contrast, the L-isoproterenol-elicited increase of cAMP was unaffected by the alpha-adrenergic and dopamine receptor-blocking agents phentolamine and haloperidol. These data indicate that L-isoproterenol stimulates cAMP formation in the rat thoracic duct by a specific interaction with beta-adrenergic receptors positively coupled to adenylate cyclase.
Amenta
F
F
Dipartimento di Scienze Neurologiche, Università la Sapienza, Rome, Italy.
De Rossi
M
M
Fruschelli
C
C
Gerli
R
R
D000262:Adenylyl Cyclases / Q000378:metabolism*; D000818:Animals; D000242:Cyclic AMP / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D007545:Isoproterenol / Q000494:pharmacology; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D011943:Receptors, Adrenergic, beta / Q000502:physiology*; D013566:Sympathomimetics / Q000494:pharmacology; D013897:Thoracic Duct / Q000378:metabolism / Q000502:physiology*
D011943:Receptors, Adrenergic, beta; D013566:Sympathomimetics; D000242:Cyclic AMP; D000262:Adenylyl Cyclases; D007545:Isoproterenol