Stimulation of anterior pituitary adenyl cyclase activity and adenosine 3':5'-cyclic phosphate by hypothalamic extract and prostaglandin E1.

Hypothalamic extract, containing the releasing factors for anterior pituitary hormones, within minutes stimulated adenyl cyclase activity and adenosine 3':5'-cyclic phosphate (cyAMP) concentrations in rat anterior pituitary in vitro. Cerebral cortical extract was ineffective and hypothalamic extract had no effect on these parameters in posterior pituitary or thyroid. Prostaglandin E(1) also increased adenyl cyclase activity and cyAMP levels in anterior pituitary tissue.

Thyroid-stimulating hormone and prostaglandin E1 stimulation of cyclic 3',5'-adenosine monophosphate in thyroid slices.

Thyroid-stimulating hormone increased the cyclic 3',5'-adenosine monophosphate concentration in dog thyroid slices during a 1-minute incubation period and produced a maximum effect soon thereafter. The elevation persisted for at least 30 minutes. The concentrations of the cyclic 3',5'-adenosine monophosphate increased as the TSH concentration was increased from 0.