Effect of phenylarsine oxide on hepatic alpha 1-adrenoreceptor responsiveness. Dissociation between ionotropic and metabolic responses.
The present studies analyze the effect of the tervalent arsenical compound phenylarsine oxide (PAO) on hepatic response to alpha 1-adrenoreceptor stimulation. PAO, while not significantly altering the rate of glycogen breakdown, was found to inhibit many characteristic alpha 1-adrenoreceptor mediated responses including H+ and Ca2+ release, increased energy production, and vascular smooth muscle contraction. PAO inhibited basal gluconeogenesis but failed to inhibit the alpha 1-agonist induced stimulation of glucose production. These data suggest that alpha 1-adrenoreceptor mediated stimulation of metabolism and rates of ion flux across the plasma membrane are separate processes and that exchange in ion homeostasis is not essential to elicit the receptor-mediated metabolic responses. The selective effect of PAO offers an interesting tool for studying the alpha 1-adrenoreceptor signaling mechanisms.
Urcelay
E
E
Department of Human Pathology and Molecular Genetics, (CSIC), Madrid, Spain.
Butta
N
N
Ayuso
M S
MS
Parrilla
R
R
D000818:Animals; D001152:Arsenicals / Q000494:pharmacology*; D002118:Calcium / Q000378:metabolism; D005502:Food; D005943:Gluconeogenesis / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects; D017136:Ion Transport / Q000187:drug effects; D008099:Liver / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D011522:Protons; D051381:Rats; D017208:Rats, Wistar; D018340:Receptors, Adrenergic, alpha-1 / Q000187:drug effects*; D012964:Sodium / Q000378:metabolism; D013217:Starvation
D001152:Arsenicals; D011522:Protons; D018340:Receptors, Adrenergic, alpha-1; C029341:oxophenylarsine; D012964:Sodium; D002118:Calcium