Role of Nitric Oxide in the alterations in HPA Axis induced in prenatally stressed offspring

MAUR, D.; BURDET, B.; RIOS, H.; GENARO, A.; ZORRILLA ZUBILETE.M.A.

Congreso; Sociedad Argentina de Investigación en Neurociencias; 2011

A great amount of evidence has shown that prenatal restraint stress (PRS) induces alterations in hypothalamic-pituitary-adrenal (HPA) axis responsiveness. Evidence has pointed out to a role of the hippocampus in modulating the response to stress. The aim of the present work was to find a possible link between the alterations induced in nitric oxide (NO) and the reported alterations in HPA axis. Methods: pregnant Wistar rats were restrained three times a day during the last week of pregnancy. Offspring was sacrificed at early ages and at adulthood for corticosterone (cort) determination and NADPH diaphorase histochemistry. Anxiety-like behaviour was evaluated in an open field. Results: We found an increase in immovility time in the open field in PRS rats, together with a decrease in cort secretion and NADPH diaphorase staining. To evaluate a link between NO and cort, animals were treated with an nNOS inhibitor prior to sacrifice. We found that nNOS inhibition led to a decrease in cort secretion in controls, but not in PRS rats. Discussion: Alterations in HPA axis due to PRS has previously been established. The results found here point to a role of nNOS in the modulation of corticosterone secretion, and to a participation of NO in PRS induced alterations.