Effects of SCH-23390 and Sulpiride on Active Avoidance in Ovariectomized Rats Treated with a Low Dose of 17[beta]-Estradiol

• Published in: Bulletin of experimental biology and medicine 2014-03, Vol.156 (5), p.612
• Main Authors: Fedotova, Yu O, Sapronov, N S
• Format: Article
• Language: English
• ISSN: 0007-4888; 1573-8221
• DOI: 10.1007/s10517-014-2407-2

We studied the effects of dopamine D^sub 1^/D^sub 2^ receptor antagonists on the dynamics of acquisition and extinction of active avoidance responses and open field behavior in ovariectomized female rats. Dopamine D^sub 1^ receptor antagonist SCH-23390 (0.1 mg/kg intraperitoneally) and dopamine D^sub 2^ receptor antagonist sulpiride (10.0 mg/kg intraperitoneally) were administered chronically (14 days) either alone or in combination with a low dose of 17[beta]-estradiol (0.5 [mu]g per rat subcutaneously) to females after ovariectomy. It was found that SCH-23390 in combination with a low dose of 17[beta]-estradiol completely restored impaired conditioning and retention of a conditioned avoidance response in ovariectomized animals. Simultaneous correction of behavioral patterns in the open field test was also observed in ovariectomized females receiving SCH-23390. Sulpiride injected alone or in combination with low dose of 17[beta]-estradiol did not correct conditioning and reproduction of active avoidance response in females with estrogen deficiency and did not significantly affect animal behavior. The results indicate positive effect of dopamine D^sub 1^ receptor blockade on active learning under conditions of estrogen deficiency.