Intracellular pH changes induced by exposure to weak acids and bases in submandibular cells of early postnatal rats.

The intracellular pH of submandibular cells of adult, 1-day-old and 1-week-old rats was measured with the pH sensitive fluorimetric indicator SNARF-1, following shifts induced by exposure to a weak acid (sodium butyrate) or a weak base (NH4Cl). The effects of several ion transport inhibitors and agonists on both the pH change and the rate of recovery were examined. The results indicate that, in most respects, the processes involved in pH regulation were similar in the neonatal and mature cells. However, cholinergic and peptidergic stimulation accelerated recovery from sodium butyrate-induced acidification more, and from NH4Cl-induced alkalinization less, in cell preparations from 1-day-old animals.