▁signal ing ▁in ▁the ▁brain , ▁thereby ▁acting ▁as ▁a ▁buffer ▁against ▁stress - related ▁dise ases ▁like ▁de pression . ▁ ▁Gl ut am ate ▁and ▁G AB A ▁ ▁Gl ut am ate , ▁one ▁of ▁the ▁most ▁common ▁ne uro chem ical s ▁in ▁the ▁brain , ▁is ▁an ▁exc itat ory ▁ne uro trans mit ter ▁involved ▁in ▁many ▁aspects ▁of ▁brain ▁function , ▁including ▁learning ▁and ▁memory . ▁Based ▁upon ▁animal ▁models , ▁exercise ▁appears ▁to ▁normal ize ▁the ▁excess ive ▁levels ▁of ▁gl ut am ate ▁ne uro trans mission ▁into ▁the ▁nucle us ▁acc umb ens ▁that ▁occurs ▁in ▁drug ▁add iction . ▁A ▁review ▁of ▁the ▁effects ▁of ▁exercise ▁on ▁ne uro card iac ▁function ▁in ▁pre cl in ical ▁models ▁noted ▁that ▁exercise - indu ced ▁ne uro pl astic ity ▁of ▁the ▁ro str al ▁vent rol ater al ▁med ulla ▁( R V LM ) ▁has ▁an ▁in hib itory ▁effect ▁on ▁gl ut am ater g ic ▁ne uro trans mission ▁in ▁this ▁region , ▁in ▁turn ▁reducing ▁sympath etic ▁activity ; ▁the ▁review ▁hypoth es ized ▁that ▁this ▁ne uro pl astic ity ▁in ▁the ▁R V LM ▁is ▁a ▁mechanism ▁by ▁which ▁regular ▁exercise ▁prevents ▁in activity - related ▁card i ov asc ular ▁disease . ▁ ▁Mon o am ine ▁ne uro trans mit ters ▁ ▁Ac et yl ch oline ▁ ▁Effect s ▁in ▁children ▁ ▁S ible y ▁and ▁E tn ier ▁( 2 0 0