Effect of nimodipine on the learning and memory in pentylenetetrazole-induced chronic epileptic rats

Objective To explore the effect of nimodipine （NIM） on learning and memory in pcntylcnetetrazole（PTZ）-induced chronic epileptic rats and the concentration of intracellular free calcium（ [ Ca^2＋ ]i ） in hippocampal cells. Methods 120 rats were divided into normal control group （group A ）, PTZ kindling epilepsy group（ group B） ,NIM 1.25mg/kg group（ group C） and NIM 2.5mg/kg group（ group D）. Use chronic model of epilepsy induced by PTZ intraperitoneal injection and NIM were administered intraperitoneally. The ability of learning and memory were assessed by the Morris water maze and Y maze. the intracellular [ Ca^2＋ ] ; was tested by flow cytometry. Results Compared with group B, the escape latency of group C and group D [ （5.94 ± 1.19 ） s, （5.69 ±1.03）s],[（7.71±1.30）s] was shortened （P〈0.05）,crossing times in platform [ （ 8. 58 ± 2.12 ） times , （ 7.51 ± 2.05 ） times, （5.73 ± 2.14 ） times ] area were increased in Morris water maze test （ P 〈 0.01 ）, the total error[（8.75 ± 2.22）times,（8.00 ± 3.16） times,（12.75±2.50） times]was decreased in Y maze test（P〈 0.05 ） and intracellular [ Ca^2 ＋ ] i [ （ 1.32 ± 0.26）, （ 1.31 ± 0.35 ）, （ 1.94 ± 0.33 ） ] was decreased （ P 〈 0.05 ）. Conclusion Phenomenon of calcium overload in chronic epileptic rats kindled by PTZ was relieved, and the ability of learning and memory were improved by NIM intraperitoneal injection. Key words: Nimodipine;  Epilepsy;  Learning and memory;  Morris water maze;  Y maze