Protein kinase C regulation of cardiac calcium channels expressed in Xenopus oocytes - PubMed (original) (raw)
. 1992 Jun;421(2-3):247-55.
doi: 10.1007/BF00374834.
Affiliations
- PMID: 1326746
- DOI: 10.1007/BF00374834
Protein kinase C regulation of cardiac calcium channels expressed in Xenopus oocytes
E Bourinet et al. Pflugers Arch. 1992 Jun.
Abstract
L-Type cardiac Ca2+ channels expressed in Xenopus oocyte were studied following rat heart ribonucleic acid, messenger (mRNA) injection. We demonstrate that exogenous Ca2+ channels are sensitive to intracellular regulation by protein kinase C (PKC). This was performed by using two types of PKC activators [phorbol esters and a structural analogue of diacyl-glycerol (DAG)] and a specific peptidic inhibitor. Ca2+ channel modulation resulted in an initial increase of the inward current, without any modification of the voltage-dependent properties, and a second delayed phase, specifically observed with phorbol esters, characterized by a progressive decrease in current amplitude. Concomitantly, a reduction of membrane capacitance, reflecting a reduction of the total membrane surface area, was observed. We suggest that this phenomenon underlies the irreversible decrease of the expressed Ba2+ current via sequestration of Ca2+ channels and/or PKC. We also demonstrate that regulation of cardiac mRNA-directed Ca2+ channels by PKC activators was strictly dependent on intracellular Ca2+ concentration, and was partially additive with cyclic-adenosine-monophosphate-(cAMP) dependent regulation.
References
- Annu Rev Physiol. 1990;52:257-74 - PubMed
- Mol Cell Biochem. 1991 May 15;103(2):171-80 - PubMed
- Pflugers Arch. 1988 Aug;412(3):328-30 - PubMed
- N Engl J Med. 1982 Jul 22;307(4):205-11 - PubMed
- Nature. 1988 Aug 25;334(6184):661-5 - PubMed
Publication types
MeSH terms
Substances
LinkOut - more resources
Miscellaneous