The study of effects of inhibition of the renin angiotensin system on memory in rats

Background: The existence of an independent renin angiotensin aldosterone system (RAAS) has been well-established and is known to modulate various pathological processes such as neuroinflammation, neurodegeneration, and neural injury, in addition to the RAAS in the cardiovascular system.Methods: Eighteen Wistar rats were divided into 3 study groups (n=6; Losartan, Ramipril, Normal Saline), trained on the Cook’s Pole climbing apparatus till the conditioned avoidance response (CAR) rate was 100%. The retention of CAR was tested each week for 4 consecutive weeks. The number of times that the animal successfully avoided the shock, and the time taken for this avoidance were measured and compared with placebo (Normal Saline). The values have been expressed as Mean±Standard Deviation (SD). A p-value of less than 0.05 has been considered as significant.Results: The retention of the conditioned avoidance response in the group receiving study drugs was significantly more than the placebo group. However, there was no show significant difference between Losartan and Ramipril in the rate of retention, or the time taken for avoidance.Conclusions: In this study, Ramipril and Losartan have a beneficial effect on learning and memory as compared to plcebo