Cultured tumor cells of murine submandibular gland origin: a model to investigate pH(i) regulation of salivary cells

Intracellular pH (pH(i)) and several ion transport mechanisms in cultured m urine salivary gland cells (SCA-9) were studied using a videomicrofluoromet ric method and the H+-specific probe C-SNARF-1. The aim of this study was t o test SCA-9 cells' pHi regulation mechanisms and evaluate if this cell lin e is representative of submandibular gland cells. Resting pHi in unstimulat ed cells was estimated to be 7.17+/-0.07. To investigate the presence of Na +/H+ and Cl-/HCO3- antiports as well as Na+/K+/2Cl(-) symports in SCA-9 cel ls, we used different specific blockers, dimethyl-amiloride, disulfonic sti lbene, bumetanide and furosemide. In order to study SCA-9 cell capacity to regulate their pHi in response to alkaline and acid loads, we applied the N H4Cl prepulse method to all these blockers. The results showed that SCA-9 c ells possess both antiports and symports involved in pHi regulation, and th at this cell line can be used as a convenient model to study pHi regulatory mechanisms in salivary cells.