Adrenergic regulation of ureogenesis in hepatocytes from adrenalectomized rats. Possible involvement of two pathways of signal transduction in alpha 1-adrenergic action.
In hepatocytes from control rats, the ureogenic action of epinephrine is mainly mediated through alpha 1-adrenoceptors and the effect is independent of the presence of extracellular calcium. In hepatocytes from adrenalectomized rats, both alpha 1- and beta-adrenoceptors are involved in the action of epinephrine. Furthermore, the alpha 1-adrenergic-mediated stimulation of ureogenesis in these cells is dependent on the presence of extracellular calcium. Our results indicate that glucocorticoids modulate the calcium dependency of alpha 1-adrenergic effects and are consistent with our suggestion that two pathways are involved in the transduction of the alpha 1-adrenergic signal.
D000315:Adrenalectomy; D000818:Animals; D004837:Epinephrine / Q000494:pharmacology*; D005260:Female; D007545:Isoproterenol / Q000494:pharmacology*; D008099:Liver / Q000187:drug effects / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D011942:Receptors, Adrenergic, alpha / Q000187:drug effects / Q000502:physiology*; D014508:Urea / Q000096:biosynthesis*
D011942:Receptors, Adrenergic, alpha; D014508:Urea; D007545:Isoproterenol; D004837:Epinephrine