Time Course of Changes in Passive Avoidance and Y-maze Performance in Male Diabetic Rats

Diabetes mellitus is accompanied with disturbances in learning, memory, and cognitive skills in the human society and experimental animals. Therefore, this research study was conducted to evaluate time-dependent changes in passive avoidance and Y-maze performance in male diabetic rats. For this purpose, male Wistar rats were randomly divided into control and diabetic groups. For induction of diabetes, streptozotocin (STZ) was injected i.p. at a single dose of 60 mg/kg. For evaluation of learning and memory, initial latency (IL) and step-through latency (STL) were determined at the end of 1 st , 2 nd , and 3 rd months using passive avoidance and Y-maze tasks. It was found out that mean IL exhibits a significant increase only at the end of 2 nd (p<0.05) and 3 rd (p<0.01) months. In addition, STL significantly reduced at the end of 2 nd (p<0.05) and 3 rd months (p<0.01). Regarding Y-maze task, alternation score of the diabetic rats was lower than that of the control ones at the end of 1 st (p<0.05), 2 nd (p<0.01), and 3 rd (p<0.01) months as compared to time-matched control group. To conclude, at least one month is strictly required for development of behavioral disturbances in passive avoidance and Y-maze tasks in STZ-diabetic rats.