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Pharmacological Dissection of the Crosstalk between NaV and CaV Channels in GH3b6 Cells.

ABSTRACT: Thanks to the crosstalk between Na+ and Ca2+ channels, Na+ and Ca2+ homeostasis interplay in so-called excitable cells enables the generation of action potential in response to electrical stimulation. Here, we investigated the impact of persistent activation of voltage-gated Na+ (NaV) channels by neurotoxins, such as veratridine (VTD), on intracellular Ca2+ concentration ([Ca2+]i) in a model of excitable cells, the rat pituitary GH3b6 cells, in order to identify the molecular actors involved in Na+-Ca2+ homeostasis crosstalk. By combining RT-qPCR, immunoblotting, immunocytochemistry, and patch-clamp techniques, we showed that GH3b6 cells predominantly express the NaV1.3 channel subtype, which likely endorses their voltage-activated Na+ currents. Notably, these Na+ currents were blocked by ICA-121431 and activated by the β-scorpion toxin Tf2, two selective NaV1.3 channel ligands. Using Fura-2, we showed that VTD induced a [Ca2+]i increase. This effect was suppressed by the selective NaV channel blocker tetrodotoxin, as well by the selective L-type CaV channel (LTCC) blocker nifedipine. We also evidenced that crobenetine, a NaV channel blocker, abolished VTD-induced [Ca2+]i elevation, while it had no effects on LTCC. Altogether, our findings highlight a crosstalk between NaV and LTCC in GH3b6 cells, providing a new insight into the mode of action of neurotoxins.

SUBMITTER: Rethore L

PROVIDER: S-EPMC8775721 | biostudies-literature | 2022 Jan

REPOSITORIES: biostudies-literature

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Pharmacological Dissection of the Crosstalk between NaV and CaV Channels in GH3b6 Cells.

Réthoré Léa L Park Joohee J Montnach Jérôme J Nicolas Sébastien S Khoury Joseph J Le Seac'h Elodie E Mabrouk Kamel K De Pomyers Harold H Tricoire-Leignel Hélène H Mattei César C Henrion Daniel D Fajloun Ziad Z De Waard Michel M Legendre Claire C Legros Christian C

International journal of molecular sciences 20220113 2

Thanks to the crosstalk between Na+ and Ca2+ channels, Na+ and Ca2+ homeostasis interplay in so-called excitable cells enables the generation of action potential in response to electrical stimulation. Here, we investigated the impact of persistent activation of voltage-gated Na+ (NaV) channels by neurotoxins, such as veratridine (VTD), on intracellular Ca2+ concentration ([Ca2+]i) in a model of exc ...[more]

PMID: 35055012

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Dataset Information

Pharmacological Dissection of the Crosstalk between NaV and CaV Channels in GH3b6 Cells.

Publications

Pharmacological Dissection of the Crosstalk between Na<sub>V</sub> and Ca<sub>V</sub> Channels in GH3b6 Cells.

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