Abstract
Background: Angiotensin II receptor blockers and Angiotensin-converting enzyme inhibitors are widely used drugs for cardiovascular disorders, renal disease, and diabetes. Recently, they have been recognized for neuroprotective activity and are used in many brain disorders.

Aim and Objective: The present study was done to explore effects of perindopril and valsartan on experimentally induced learning and memory impairment in Wistar rats.

Materials and Methods: 40 Wistar rats were divided into 5 groups, eight rats in each group, namely normal control, disease control, positive control (Piracetam 600 mg/kg), test group I (Perindopril 4 mg/kg), and test group II (Valsartan 15 mg/kg). Except normal control group, all animals received intraperitoneal injection of Scopolamine 1 mg/kg for 21 days to induce memory impairment. Piracetam and Test drugs were administered once daily orally for 21 consecutive days. On day 0, 7th, 14th, and 21st of the experiment, muscle grip strength (Wire hanging grip test) and memory functions Elevated plus maze (EPM) of all the animals were assessed. On 8th, 15th, and 22nd day of the experiment, retention memory functions (EPM) were assessed.

Results: Animals treated with Scopolamine showed significant reduction in grip strength and significant rise in transfer latency (TL) (EPM model). Rats treated with piracetam and test drugs showed significant increase in grip strength. The animals treated with piracetam and test drugs showed significant reduction in TL (EPM model) when compared with disease control group. Similar results were seen in retention memory test.

Conclusion: Perindopril and valsartan demonstrated neuroprotective effect in scopolamine-induced memory impairment in rats. Memory improvement by these test drugs was comparable with positive control piracetam.

Key words: Scopolamine; Perindopril; Valsartan; Neuroprotection