Merck
  • Home
  • Search Results
  • The sodium leak channel NALCN regulates cell excitability of pituitary endocrine cells.

The sodium leak channel NALCN regulates cell excitability of pituitary endocrine cells.

FASEB journal : official publication of the Federation of American Societies for Experimental Biology (2021-04-02)
Hathaichanok Impheng, Céline Lemmers, Malik Bouasse, Christian Legros, Narawut Pakaprot, Nathalie C Guérineau, Philippe Lory, Arnaud Monteil
ABSTRACT

Anterior pituitary endocrine cells that release hormones such as growth hormone and prolactin are excitable and fire action potentials. In these cells, several studies previously showed that extracellular sodium (Na+ ) removal resulted in a negative shift of the resting membrane potential (RMP) and a subsequent inhibition of the spontaneous firing of action potentials, suggesting the contribution of a Na+ background conductance. Here, we show that the Na+ leak channel NALCN conducts a Ca2+ - Gd3+ -sensitive and TTX-resistant Na+ background conductance in the GH3 cell line, a cell model of pituitary endocrine cells. NALCN knockdown hyperpolarized the RMP, altered GH3 cell electrical properties and inhibited prolactin secretion. Conversely, the overexpression of NALCN depolarized the RMP, also reshaping the electrical properties of GH3 cells. Overall, our results indicate that NALCN is functional in GH3 cells and involved in endocrine cell excitability as well as in hormone secretion. Indeed, the GH3 cell line suitably models native pituitary cells that display a similar Na+ background conductance and appears as a proper cellular model to study the role of NALCN in cellular excitability.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
N-Methyl-D-glucamine, 99.0-100.5% (titration)
Sigma-Aldrich
Puromycin dihydrochloride from Streptomyces alboniger, powder, BioReagent, suitable for cell culture
Sigma-Aldrich
G 418 disulfate salt, powder, BioReagent, suitable for cell culture
Roche
cOmplete, Mini Protease Inhibitor Cocktail, Tablets provided in EASYpacks