ons ▁perform ▁neur om od ulation , ▁which ▁is ▁the ▁release ▁of ▁neur om od ul ators . ▁ ▁Ne ur om od ul ators ▁differ ▁from ▁classical ▁ne uro trans mit ters . ▁Typ ically , ▁neur om od ul ators ▁do ▁not ▁directly ▁generate ▁elect rical ▁responses ▁in ▁target ▁neur ons . ▁ ▁R ather , ▁the ▁release ▁of ▁neur om od ul ators ▁often ▁al ters ▁the ▁effic acy ▁of ▁ne uro trans mission ▁in ▁nearby ▁chemical ▁syn aps es . ▁ ▁Furthermore , ▁the ▁impact ▁of ▁neur om od ul ators ▁is ▁often ▁quite ▁long ▁last ing ▁in ▁comparison ▁to ▁classical ▁ne uro trans mit ters . ▁ ▁A ▁number ▁of ▁ne uro trans mit ters ▁can ▁act ▁as ▁neur om od ul ators , ▁particularly ▁bi ogen ic ▁am ines ▁such ▁as ▁dop am ine ▁and ▁ser ot on in . ▁These ▁neur om od ul ators ▁use ▁G - prote in ▁couple d ▁re cept ors ▁which ▁medi ate ▁slower ▁mod ul atory ▁effects ▁and ▁neither ▁hyper pol ar ize ▁nor ▁dep olar ize ▁cells . ▁Due ▁to ▁these ▁qual ities , ▁G PC R ▁can ▁initi ate ▁long - last ing ▁changes ▁in ▁heter os yn apt ic ▁strength . ▁ ▁The ▁use ▁of ▁these ▁neur om od ul ators ▁is ▁an ▁example ▁of ▁heter os yn apt ic ▁pl astic ity . ▁Re leased ▁by ▁a ▁neur on ▁called ▁an ▁inter neur on , ▁neur om od ul ators ▁can ▁affect ▁another ▁neur on '