RT Book, Section
A1 Freeman, Brian S.
A2 Freeman, Brian S.
A2 Berger, Jeffrey S.
SR Print(0)
ID 1102570019
T1 Dopaminergic Drugs
T2 Anesthesiology Core Review: Part One Basic Exam
YR 2014
FD 2014
PB McGraw-Hill Education
PP New York, NY
SN 9780071821377
LK accessanesthesiology.mhmedical.com/content.aspx?aid=1102570019
RD 2024/04/19
AB Dopamine  is  one  of  several  endogenous  catecholamines  that  serve  as  neurotransmitters  within  the  central  and  autonomic  (sympathetic)  nervous  systems.  Dopamine  is  synthesized  in  neurons  of  the  central  nervous  system,  particularly  the  substantia  nigra  and  the  ventral  tegmental  area,  and  the  adrenal  medulla.  Dopamine  is  derived  from  its  precursor,  l-dihydroxyphenylalanine  (l-DOPA),  by  the  enzyme  DOPA  decarboxylase.  Dopamine  then  becomes  a  precursor  in  the  synthesis  of  norepinephrine  and  epinephrine,  two  very  important  catecholamines.  It  does  not  cross  the  blood-brain  barrier.  Endogenous  dopamine  has  a  half-life  of  one  minute.  It  is  rapidly  metabolized  into  inactive  metabolites  by  the  enzymes  monoamine  oxidase  (MAO)  and  catechol-o-methyl  transferase  (COMT).  Homovanillic  acid,  the  primary  metabolite,  is  excreted  into  the  urine.