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Angiotensin II-induced increase of T-type Ca2+ current and decrease of L-type Ca2+ current in heart cells.

Ghassan Bkaily·Adrian Sculptoreanu·Shimin Wang·Moni Nader·Khaled M Hazzouri·Danielle Jacques·Domenico Regoli·Pedro D'Orleans-Juste·Levon Avedanian
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Abstract

The effect of angiotensin II (Ang II) on the T- and L-type calcium currents (I(Ca)) in single ventricular heart cells of 18-week-old fetal human and 10-day-old chick embryos was studied using the whole-cell voltage clamp technique. Our results showed that in both, human and chick cardiomyocytes, Ang II (10(-7)M) increased the T-type calcium current and decreased the L-type I(Ca). The effect of Ang II on both types of currents was blocked by the AT1 peptidic antagonist, [Sar1, Ala8] Ang II (2 x 10(-7)M). Protein kinase C activator, phorbol 12,13-dibutyrate, mimicked the effect of Ang II on the T- and L-type calcium currents. These results demonstrate that in fetal human and chick embryo cardiomyocytes Ang II affects the T- and L-type Ca2+ currents differently, and this effect seems to be mediated by the PKC pathway.

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Angiotensin IIAnimalsCalciumCalcium Channels, L-TypeCalcium Channels, T-TypeChick EmbryoDose-Response Relationship, DrugElectrophysiologyHeart VentriclesHumansIndolesMaleimidesMyocytes, CardiacPhorbol 12,13-DibutyrateProtein Kinase CSignal TransductionTime FactorsVentricular FunctionJournal ArticleResearch Support, Non-U.S. Gov't

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Ghassan Bkaily, Adrian Sculptoreanu, Shimin Wang, Moni Nader, Khaled M Hazzouri, Danielle Jacques, Domenico Regoli, Pedro D'Orleans-Juste, Levon Avedanian. 2005-04-08. Angiotensin II-induced increase of T-type Ca2+ current and decrease of L-type Ca2+ current in heart cells.. https://doi.org/10.1016/j.peptides.2005.03.021

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