| BackgroundInformation | Thechemicalcompoundnorepinephrine(NC(8)O(3)H(11),alsoknownasnoradrenaline,isacatecholaminethatfunctionsasbothaneurotransmitterandahormone.Itisreleasedfromtheadrenalglandsandalsobycertainneurons.Itaffectspartsofthehumanbrainwhereattentionandimpulsivityarecontrolled.Thiscompoundaffectsthefight-or-flightresponse,activatingthesympatheticnervoussystemtodirectlyincreaseheartrate,releaseenergyfromfatandincreasemusclereADIness.
 
 
  Thehostofphysiologicalchangesactivatedbyastressfuleventareunleashedinpartbyactivationofanucleusinthebrainstemcalledthelocusceruleus.Thisnucleusistheoriginofmostnorepinephrinepathwaysinthebrain.Neuronsusingnorepinephrineastheirneurotransmitterprojectbilaterallyfromthelocusceruleusalongdistinctpathwaystothecerebralcortex,limbicsystem,andthespinalcord,amongotherprojections. |