A Gi1-2-protein is required for alpha 2A-adrenoceptor-induced stimulation of voltage-dependent Ca2+ channels in rat portal vein myocytes.
In rat portal vein myocytes, alpha 2A-adrenoceptors activate voltage-dependent Ca2+ channels via a transduction pathway requiring protein kinase C activation mediated by a pertussis-toxin-sensitive G-protein. As revealed by the use of antibodies directed against the different alpha-subunits expressed in portal vein myocytes, we show that the clonidine-induced stimulation of voltage-dependent Ca2+ channels is mainly mediated by a Gi1-2-protein.
D000316:Adrenergic alpha-Agonists / Q000494:pharmacology; D000818:Animals; D015220:Calcium Channels / Q000187:drug effects / Q000378:metabolism*; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism; D003000:Clonidine / Q000494:pharmacology; D004591:Electrophoresis, Polyacrylamide Gel; D004594:Electrophysiology; D004789:Enzyme Activation / Q000502:physiology; D019204:GTP-Binding Proteins / Q000378:metabolism*; D015151:Immunoblotting; D066298:In Vitro Techniques; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D018408:Patch-Clamp Techniques; D011169:Portal Vein / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D011493:Protein Kinase C / Q000378:metabolism; D011817:Rabbits; D051381:Rats; D018341:Receptors, Adrenergic, alpha-2 / Q000187:drug effects / Q000502:physiology*; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology
D000316:Adrenergic alpha-Agonists; D015220:Calcium Channels; D018341:Receptors, Adrenergic, alpha-2; D011493:Protein Kinase C; D019204:GTP-Binding Proteins; D003000:Clonidine