Cell-Type-Specific Expression Pattern of Proton-Sensing Receptors and Channels in Pituitary Gland.

Autor: Wang K; Section on Cellular Signaling, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland., Kretschmannova K; Section on Cellular Signaling, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland., Prévide RM; Section on Cellular Signaling, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland., Smiljanic K; Section on Cellular Signaling, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland., Chen Q; Section on Cellular Signaling, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland., Fletcher PA; Laboratory of Biological Modeling, National Institute of Diabetes, Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland., Sherman A; Laboratory of Biological Modeling, National Institute of Diabetes, Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland., Stojilkovic SS; Section on Cellular Signaling, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland. Electronic address: stojilks@mail.nih.gov.
Jazyk: angličtina
Zdroj: Biophysical journal [Biophys J] 2020 Dec 01; Vol. 119 (11), pp. 2335-2348. Date of Electronic Publication: 2020 Oct 22.
DOI: 10.1016/j.bpj.2020.10.013
Abstrakt: In mammalian cells, extracellular protons act as orthosteric and allosteric ligands for multiple receptors and channels. The aim of this study is to identify proton sensors in the rat pituitary gland. qRT-PCR analysis indicated the expression of G-protein-coupled receptor 68 gene (Gpr68) and acid-sensing ion channel (ASIC) genes Asic1, Asic2, and Asic4 in anterior pituitary cells and Asic1 and Asic2 in immortalized GH3 pituitary cells. Asic1a and Asic2b were the dominant splice isoforms. Single anterior pituitary cell RNA sequencing and immunocytochemical analysis showed that nonexcitable folliculostellate cells express GPR68 gene and protein, whereas excitable secretory cells express ASIC genes and proteins. Asic1 was detected in all secretory cell types, Asic2 in gonadotrophs, thyrotrophs, and somatotrophs, and Asic4 in lactotrophs. Extracellular acidification activated two types of currents in a concentration-dependent manner: a fast-developing, desensitizing current with an estimated EC 50 -value of pH 6.7 and a slow-developing, non-desensitizing current that required a higher proton concentration for activation. The desensitizing current was abolished by removal of bath sodium and application of amiloride, a blocker of ASIC channels, whereas the non-desensitizing current was amiloride insensitive and voltage dependent. Activation of both currents increased the excitability of secretory pituitary cells, consistent with their potential physiological relevance in control of voltage-gated calcium influx and calcium-dependent cellular functions.
(Published by Elsevier Inc.)
Databáze: MEDLINE
Externí odkaz: