Interaction effects of intra-hippocampal injection of citalopram with estrogen and progesterone on passive avoidance memory and motor balance in male Wistar rats

This study was investigated the interaction effects of the intra-hippocampal injection of citalopram with estrogen and progesterone on passive avoidance memory and motor balance in male Wistar rats.

This experimental study was conducted on the 25 male Wistar rats. Passive avoidance memory measured by shuttle box device and movement balance examined by the rotarod device. Animal randomly assigned into 5 groups, group 1: saline, group 2: citalopram (2 nmol), group 3: citalopram (2 nmol) + estrogen (1 nmol), group 4: citalopram (2 nmol) + progesterone (1 nmol), and group 5 citalopram (2 nmol) + estrogen (1 nmol) + progesterone (1 nmol). In all groups, the final injection volume was 1.5 μl in left or right hippocampi.

Citalopram received group increased the latency for entering the dark areas and the total time the animals have spent in the light compartment. It shows that citalopram has increased passive avoidance memory (p < 0.001). When the citalopram was injected with steroid hormones into the hippocampus, there was a significant increase in learning and memory activity in rats (p < 0.01). In the motor balance test initially, there was no significant difference observed between the control groups. After receiving the injections at 1,3 and 24-h intervals, a significant decrease in motor balance was observed compared to the other control groups (p < 0.01).

Intra-hippocampal injection of citalopram increased the passive avoidance learning process in rats receiving the drug. On the other hand, citalopram reduces motor balance when combined with estrogen and progesterone.