Abstract
In rat portal vein myocytes, α2A-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 α-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.
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References
Leprêtre N, Mironneau J, Morel JL (1994) Both α1a- and α2a-adrenoreceptor subtypes stimulate voltage-operated L-type calcium channels in rat portal vein myocytes: evidence for two distinct transduction pathways. J Biol Chem 269:29546–29552
Leprêtre N, Mironneau J (1994) α2adrenoceptors activate dihydropyridine-sensitive calcium channels via Gi-protein and protein kinase C in rat portal vein myocytes. Pflügers Arch 429:253–261
Rouot B, Charpentier N, Chabbert C, Carrette J, Zumbihl R, Bockaert J, Homburger V (1991) Specific antibodies against Go isoforms reveal the early expression of the Go2α submit and appearance of Go1α during neuronal differentiation. Mol Pharmacol 41:273–280
Guillon G, Butlen D, Rajerison R (1984) Evidence for two molecular forms of solubilized vasopressin receptors in rat kidney membranes. Regulation by guanyl nucleotides. Mol Pharmacol 26:241–247
Spiegel AM, Schenker A, Weinstein LS (1992) Receptor-effector coupling by G-proteins. Endocr Rev 13:536–565
Remaury A, Larrouy D, Daviaud D, Rouot B, Paris H (1993) Coupling of the α2-adrenergic receptor to the inhibitory G-protein Gi and adenylate cyclase in HT29 cells. Biochem J 292:283–288
Gollasch M, Kleuss C, Hescheler J, Wittig B, Schulte G (1993) Gi2 and protein kinase C are required for thyrotropin-releasing hormone-induced stimulation of voltage-dependent Ca2+ channels in rat pituitary GH3 cells. Proc Natl Acad Sci USA 90: 6265–6269
Kurose H, Regan JW, Caron MG, Lefkowitz RJ (1991) Functional interactions of recombinant α2 adrenergic receptor subtypes and G proteins in reconstituted phospholipid vesicles. Biochemistry 30:3335–3341
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Macrez-Leprêtre, N., Ibarrondo, J., Arnaudeau, S. et al. A Gi1–2-protein is required for α2A-adrenoceptor-induced stimulation of voltage-dependent Ca2+ channels in rat portal vein myocytes. Pflugers Arch. 430, 590–592 (1995). https://doi.org/10.1007/BF00373897
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DOI: https://doi.org/10.1007/BF00373897