Electrogenic NBCel (SLC4A4), but not electroneutral NBCnl (SLC4A7),cotransporter undergoes cholinergic-stimulated endocytosis in salivary parC5 cells

摘要

Moreover, mutations and deletions of NBC genes are major culprits of poor dentition in humans and mice (16, 19, 23). NBC was functionally detected in bovine and sheep parotid acinar cells before cloning of the SLC4 gene family (45, 50, 59). These reports were confirmed by a more recent report that electrogenic NBCel (SLC4A4) is present and functional in bovine parotid acinar cells (66). Additionally, several groups reported abundant expression of NBCel and NBCnl in parotid acinar cells of different species (53). However, nothing is known about regulation of NBC by cholinergic secretory stimuli in parotid acinar cells. In fact, so little attention has been given to potential roles that NBC could play in the fluid secretion process that current models of fluid secretion proposed for parotid acinar cell do not include NBC (20, 39, 41). It is critical to clarify the roles of NBC in parotid acinar cells for a thorough understanding of the molecular physiology of the fluid secretion process