Effect of posttraining injections of glucocorticoid agonist and antagonist into the dorsal hippocampus on spatial memory storage in place avoidance learning task

How to Cite:Abbas Ali Vafaei, Ali RashidiPor, MohammadReza Sharifi, Jahn Borsh, Effect of posttraining injections of glucocorticoid agonist and antagonist into the dorsal hippocampus on spatial memory storage in place avoidance learning task.koomesh.2000;1(3):e153107.

Abstract

Introduction. T he presen t ex periment exam ined th e effec t of posttraining injections of glucocorticoid ago nist and a ntagonist into th e dorsal hippocamp us (DH) o n re te nt ion of spa tia l memory in p lace avoida nce lea rn ing task. Materials and Methods. Ma le Long-Eva ns strai n rats wer e surgically implanted bi late ra lly with cannu lae a imed at the DH a nd were train ed to avoid a f,O degree segment of th e are na en tering which was punished by mild fnotsh ock. Pla ce avo ida nce tra in ing occu rred in a singl e 30-min sess ion a nd th e avo ida nce memory was assess e e! duri ng a 30-min extinctio n tr ial 24 h later. T he time to the first e ntry a nd th e num ber of entran ces into the p unished sector d ur ing extinctio n we re use d to me asure the place avoida nce memory. Dexame th asone (0. 1 ,u g/O,(~u J, pe r side ) as a glucocort ico id agonist and RU384486 (3 ng/0.6 ,ul pe r s ide ) as a gluco corticoid antagonist were inject ed bilaterally int o DH immediate ly and 60 and J20 min a fte r trai ning. Re tentio n test was doneone days later. Results. Results indicated that infusio n of glu coc ortico id ago nist a nd antagonist immed iately a nd 60 min but not 120 min afte r tr aining into DH significa ntly e nhanced and impa ired ret e ntion pe rformance, respective ly. Conclusion. T he above results show that glucocorticoid receptor plays a n important ro le in consolidation of sp atial memory in place avoidance learni ng at least 60 min afte r training.

Keywords

H ippocampus: Spatia l memory

گیرنده گلوکوکورتیکویید

هیپوکمپ

ذخیره حافظه فضایی

یادگیری احترازی مکانی

comments