[Stereospecificity of hypothalamo-hypophysial dopamine receptors involved in the control of prolactin secretion in normal man: effects of sulpiride stereoisomers].

The sterical requirements of dopamine (DA) receptors involved in the control of prolactin (PL) secretion have been analyzed by studying the effects of the administration of d- and l-sulpiride (25 mg i.v.) on PL serum levels in five normal male volunteers. Both d- and l-sulpiride cause a remarkable rise in PL serum levels, the only difference between the two drugs being the lower decay rate of hormone levels after the l-isomer. The results obtained are discussed in the frame of a possible low steric selectivity of DA receptors controlling PL secretion in the hyposthalamo-pituitary axis.