The effect s of muscimol injection into basolateral amygdala on spatial memory processing in place avoidance learning task

Introduction. The present experiment examined the effect of pre and posttraining and before of re tre ival test injections of muscimol, a GABA agonist, into ba solateral amygdala (BLA) on reten tion of spatia l memory in place avoida nce learning tas k. Materials and Methods. Male Long-Evans strain rats were surgi cally impl anted bila te ra lly with cannulae aimed at the BLA and were tra ined to avoid a 60 degree.segment of the are na entering which was punished by mild footshock. Place avoidance training occ urred in a single 30-min sess ion an d the avoidance memory was assesse d during a 30-min extinction tria l 24 h later. Th e time to the first entry and the num ber of entra nces into the punished sector during exti nction we re used to me asure the place avo ida nce memo ry. Mu scimo! (0.5 ,ug/0.6,u I, per side) as a GABAergic ago nist wer e injected bilatera lly and unilatera lly into BLA immediately after tra ining and before ret reival test. Retention test was done one day la ter. Results. Results indica ted that infu sion of muscimol before and immediately a ft e r tr aining into BLA significant ly impaired retention performan ce. Infusio n of muscimol be fore re treival test into BLA bil at erally and unil a terally o nly righ t amygda la not le ft significant ly impaired retention pe rformance. Conclusion. The above r esu lts show t hat GABAergi c receptor pl ays an importa nt ro le in acquisition and consolidation of spatia l memory in place avo ida nce learning. Also this res ults show that GABAergic system play an important rol e on re trei val of spa tial memory in BLA of the amygd ala and this role is very impor tant in right BLA.