Prolactin secretion by cultured anterior pituitary cells: influence of culture conditions and endocrine status of the pituitary donor.

The characteristics of prolactin (PRL) secretion by cultured anterior pituitary cells in the presence and absence of catecholamines were studied. PRL secretion was markedly influenced by culture conditions such as cell density, culture duration and length of short-term incubation. Dopamine (DA) inhibited PRL release in a dose-dependent manner within a physiological range, and this inhibition was reversed by the stereospecific DA receptor antagonist (+)-butaclamol. In contrast, the inhibition of PRL secretion by norepinephrine (NE) required much higher doses and lacked specificity. Cells obtained from male donors had the lowest basal PRL secretion and were the least responsive to DA inhibition, whereas those obtained from females in late pregnancy had the highest basal PRL secretion and were the most sensitive to DA.