Long-term treatment of anterior pituitary cells with nitric oxide induces programmed cell death.

Nitric oxide (NO) plays a complex role in modulating programmed cell death. It can either protect the cell from apoptotic death or mediate apoptosis, depending on its concentration and the cell type and/or status. In this study, we demonstrate that long-term exposition to NO induces cell death of anterior pituitary cells from Wistar female rats.

Estrogen decreases the sensitivity of anterior pituitary to the inhibitory effect of nitric oxide on prolactin release.

Objective: We investigated the effect of chronic estrogen treatment on the inhibitory action of nitric oxide (NO) on prolactin release.

Methods: The effect of NO on prolactin release was studied in anterior pituitaries of female Wistar rats, intact at random stages, ovariectomized (OVX), and OVX treated for 15 days with 17beta-estradiol (OVX-E(2)).

Results: Sodium nitroprusside (NP, 0.