...). Whether and to what extent V-ATPase contributes to intracellular pH (pH i ) regulation in unstimulated gland cells is unknown. We used the fluorescent dye BCECF to study intracellular pH i regulation microfluorometrically and show that: (1) under resting conditions, the application of Na + -free...

... with submicromolar serotonin. In the present study we investigated the mechanisms of strong luminal alkalinization using the intracellular fluorescent indicator BCECF-AM. Following stimulation with serotonin, we observed that intracellular pH (pH i ) of the anterior midgut increased from a mean of 6.89 to a mean...

...Bettina Schewe; Elmar Schmälzlin; Bernd Walz SUMMARY Blowfly salivary gland cells have a vacuolar-type H + -ATPase(V-ATPase) in their apical membrane that energizes secretion of a KCl-rich saliva upon stimulation with serotonin (5-hydroxytryptamine, 5-HT). We have used BCECF to study...

... and whether and to what extent the apical V-ATPase contributes to pH i regulation. pH i measurements with double-barrelled pH-sensitive microelectrodes and the fluorescent dye BCECF have revealed: (1) the steady-state pH i is 7.3±0.1; (2) dopamine induces a dose-dependent acidification up to pH 6.9±0.1 at 1...