RESEARCH ARTICLE
Functional Exploration Of T-Type Calcium Channels (Cav3.2 And Cav3.3) And Their Sensitivity To Zinc
Tahar Hazzaz Abouamal*, Zineb Choukairi, Fechtali Taoufiq
Article Information
Identifiers and Pagination:
Year: 2018Volume: 12
First Page: 280
Last Page: 287
Publisher ID: TOMICROJ-12-280
DOI: 10.2174/1874285801812010280
Article History:
Received Date: 30/3/2018Revision Received Date: 28/6/2018
Acceptance Date: 2/7/2018
Electronic publication date: 31/7/2018
Collection year: 2018
open-access license: This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International Public License (CC-BY 4.0), a copy of which is available at: (https://creativecommons.org/licenses/by/4.0/legalcode). This license permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Abstract
Introduction:
T-type Ca2+ channels (TTCC) are low Voltage-gated calcium channels, expressed in various tissues such as the brain and heart, and contribute to a variety of physiological functions including neuronal excitability, hormone secretion, muscle contraction, and pacemaker activity. At high concentrations, Zinc (Zn2+) is naturally attached to cell membranes and is therefore considered a reversible inhibitor of calcium. Zinc is also involved in the kinetics of sodium and potassium currents. Zinc is essential for many functions. A low zinc tenor is associated with emotional instability, digestive disorders, slow-growing and alteration of protein synthesis.
Material and Methods:
For the Cell Culture we used HEK-293/tsA-201, and for transfection, the pCDNA3 plasmid constructs encoding human CaV3.2, and CaV3.3 subunits. Electrophysiological experiments were performed using the whole cell configuration of the patch-clamp technique. T-type currents were recorded using a test pulse from a holding potential at (-100mV) to (-30 mV), data Acquisition and Analysis for Current-voltage relationships (I-V curves) were recorded for the two cloned T-type Ca2+ channels (Cav3.2, Cav3.3).
Results:
Our studies describe the behavior of these channels Cav3.2 and Cav3.3 and also their current sensitivity to Zinc (Zn2+) in transfected HEK-293/tsA-201cells. Our results show that Zn2+ applies a modulatory effect on T-type calcium channels. We observe that Zn2+ differentially modulates the CaV3.2 and CaV3.3 channels. Zn2+ preferably inhibits Cav3.2.
Conclusion:
We have demonstrated that Zn2+ differentially modulates two CaV3 channels (Cav3.2 and Cav3.3): It is a preferential blocker of CaV3.2 channels and it alters the gating behaviour of CaV3.3 channels.