Effects of dexamethasone injection into dentate gyrus of the hippocampus on memory storage in rat

authors:

avatar AbbasAli Vaffae , * , avatar Ali RashidiPor , avatar MohmmadReza Sharfi

Koomesh: Vol.1, issue 2; 25-31
published online: February 15, 2000
article type: Research Article

how to cite: Vaffae A, RashidiPor A, Sharfi M. Effects of dexamethasone injection into dentate gyrus of the hippocampus on memory storage in rat. koomesh. 2000;1(2):e151897. 

Abstract

Introduction. The present experiments examined the role of glucocorticoids in de nta t gyrus (DG) of the hippocampus on retention of passive avoida nce learning. Materials and Methods. Male wistar rats were implanted bilaterally with ca nnulae a imed at DG and were trained in one trial step-through passive avoidance task (1 rnA footshock, 1.5 s). Glucocorticoids receptor agonist dexamethasone (2.5 ,u g/ul per side) was injected bilaterally into DG immediately and 60, 90 or 120 min after training. Retention test was done two days later. Results. The dat a indicated that infusion of dexamethasone immediately and 60 min but not 90 or 120 min after training into DG significantly enhanced retention performance. Conclusion. The above results show that gluco corticoids play an important role in consolida tion of emotional memory in DG of the hippocampus at least 60 min after training.