Anterior pituitary tissue from rats was incubated at 37 C in Krebs’ Ringer’s bicarbonate in an atmosphere of 95% O2 and 5% CO2 with hourly changes of the incubation media. After a one hour preincubation, 45Ca++ was added to the media and its uptake by the pituitary tissue was determined. The digitalis glycoside, ouabain, in concentrations of 5 X 10-4 and 1 × 10-3M significantly augmented pituitary 45Ca++. This effect was dose and time dependent. Ouabain did not alter the washout kinetics for 14C inulin or affect pituitary weights suggesting that the observed changes in 45Ca++ content were the result of increased 45Ca++ accumulation. The effect of ouabain on calcium flux may be related to the stimulation of ACTH and GH release by ouabain.
ASJC Scopus subject areas