[D2-type dopaminergic receptors and anxiety-depression-like behavior in female rats]

Results of a comparative study of the effects of chronic administration of the D2-receptor agonist quinperole (0.1 mg/kg, i.p.) and the D2-receptor antagonist sulpiride (10.0 mg/kg, i.p.) for 14 days on anxiety- and depressive-like behavior in key phases of the ovarian cycle in adult female rats are presented. The model of depression in rats was implemented in Porsolt test, while the anxiety level was assessed in the elevated plus maze test. It is established that the chronic administration of quinperole produced an anxiolytic action in female rats during diesrous, estrous and proestrous phases, but failed to modify depression-like behavior during the entire ovarian cycle. Sulpiride administration resulted in anxiogenic effect in all phases of the ovarian cycle. It was also found that sulpiride produced some modulation of depression-like behavior in connection to ovarian cycle phases, which was a prodepressive action at a moderate level of estrogens and an antidepressant effect at a reduced/enhanced level of estrogen. It is suggested that the extent of involvement of D2-receptors in the mechanisms of anxiety-depressive-like behavior can vary depending on alterations of the hormonal balance during the ovarian cycle. The data obtained are indicative of a close interaction between ovarian hormonal and dopaminergic systems of the brain involved in the mechanisms of anxiety and depression.