The interaction of both male and female sex hormones with neurotransmitters has been widely investigated. In the present study different effect of scopolamine on learning and memory of male and female rats was investigate. Forty rats were divided into four groups: (1) Male, (2) Male-Scopolamine (Male-Sco), (3) Female and (4) Female-Scopolamine (Female- Sco). On a training trial, the rats were placed in the light compartment and when entered completely into the dark compartment received an electric shock . The latency time to enter the dark compartment was recorded and defined as retention trial. The animals of Male-Sco and Female-Sco groups received scopolamine(2 mg/kg, ip) 30 min before each retention trial. The time latency to enter the dark compartment in both Male-Sco and Female-Sco groups was lower than male and female groups respectively (P<0.001). The time latency in Female- Sco group was higher than Male-Sco group (P<0.001). These results suggest that deleterious effects of scopolamine on memory are gender dependent and therefore male or female hormones have probably an interaction with cholinergic system.

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