The influence of stimulation and blockade of D 2-type dopaminergic receptors on behavioral processes in female rats during key phases of ovary cycle

The present work was devoted to the comparative analysis of influence of chronic administration of D2-receptors agonist -quinperoie (0,1 mg/kg, i.p.) and D2-receptors antagonist - sulpiride (10,0 mg/kg, i.p.) for 14 days on learning/memory processes, anxiety-like and depressive-like behaviors in the adult female rats. Learning of these animals was assessed in different models: passive avoidance performance and Morris water maze. Model of depression in rats was carried out in Porsolt test. Anxiety level was assessed in the elevated plus maze. Chronic quinperoie administration to females resulted in the appearance of the passive avoidance performance in proestrous and estrous, as distinct from the control animals. Also, quinperoie improved spatial learning in proestrous and stimulated it in estrous in Morris water maze. Chronic sulpiride administration similarly impaired non-spatial and spatial learning in females during all phases of ovary cycle. It was established that chronic quinperoie administration rendered an anxiolytic action in females during diestrous, estrous and proestrous phases, but failed to modify depression-like behavior during ovary cycle. Sulpiride administration resulted in anxiogenic effect in all phases of ovary cycle in females. Also, it was noted definite modulation of depression-like behavior in connection of ovary cycle phases in rats treated with sulpiride; at moderate level of estrogens was prodepressive action while at reduced/enhanced levels of estrogen - antidepressant effect. It is suggested different extent of D2-receptors receptors involvement in the mechanisms of anxiety-depressive-like behavior at alterations of hormonal balance during ovary cycle. The results of the study suggest modulating role of D2-receptors in behavioral processes during ovary cycle in the adult female rats. Also, the data obtained indicate in a close interaction between ovary hormonal and dopaminergic systems of the brain in mechanisms of anxiety and depression.

quinperoie, sulpiride, D2-type dopaminergic receptors, learning, anxiety, depression, ovary cycle