Nitric oxide involvement in estrous cycle-dependent changes of the behavioral responses of female rats in the elevated plus-maze test.

Nitric oxide (NO)/cGMP pathway is known as a mediator in anxiety modulation. In this study, we assessed the involvement of NO pathway in the estrous cycle-related changes of anxiety level in rat. By using elevated plus-maze test, we studied the changes of serum nitrate and nitrite (NO(x)) levels in comparison to the estrous cycle-dependent changes of anxiety state.