Acid secretion and intracellular pH in isolated oxyntic cells

Abstract

This study demonstrates that isolated oxyntic cells are capable of secreting hydrochloric acid. Transitory peaks of medium acidification were observed when isolated oxyntic cells were stimulated with diffferent secretagogues. The duration of these peaks was of about 3 min and had a magnitude of about 0.5 muEquiv/hr mg dry weight. These peaks were abolished by selective inhibitors of acid secretion and/or secretagogue action. Cell pH, as measured by the DMO14C technique increases 0.13 pH units upon stimulation with db-cAMP. This change was abolished by pretreatment with SCN-. From acidification and cell pH experiments an increase of 5-10mM in base concentration inside the cell upon stimulation is calculated. These results are interpreted on the basis of the existence of a neutral anion exchange mechanism at the serosal side that serves to control the cell acid-base balance.

Simultaneous measurement and imaging of intracellular Ca2+ and H+ transport in isolated rabbit gastric glands

“…Studies of acid secretion at the cellular level have been based on isolated oxyntic cells or glands in vitro Michelangeli, 1978). The measurement of secretory activity in these preparations has relied upon indirect indices of activation.…”

“…The measurement of secretory activity in these preparations has relied upon indirect indices of activation. These include oxygen consumption, extracellular pH transients, intracellular pH and morphological changes Michelangeli, 1978;Thibodeau et al 1994). Acridine orange fluorescence has been used to localize the site of acid secretion in isolated gastric glands (Berglindh et al 1980).…”

Simultaneous measurement and imaging of intracellular Ca2+ and H+ transport in isolated rabbit gastric glands

“…Studies of acid secretion at the cellular level have been based on isolated oxyntic cells or glands in vitro (Berglindh & Obrink, 1976; Michelangeli, 1978). The measurement of secretory activity in these preparations has relied upon indirect indices of activation.…”

“…The measurement of secretory activity in these preparations has relied upon indirect indices of activation. These include oxygen consumption, extracellular pH transients, intracellular pH and morphological changes (Berglindh et al 1976; Michelangeli, 1978; Thibodeau et al 1994). Acridine orange fluorescence has been used to localize the site of acid secretion in isolated gastric glands (Berglindh et al 1980).…”

Na+-H+ exchange in gastric glands as measured with a cytoplasmic-trapped, fluorescent pH indicator.

“…In contrast, there have been few studies of the cytosolic pH (pHj) of gastric cells (1)(2)(3)(4) and none concerned with how these cells might regulate their pHc. Regulation of pH, is likely to be an important problem for all cells of the gastric mucosa.…”