TY  - CHAP
M1  - Book, Section
TI  - Widely Projecting Systems: Monoamines, Acetylcholine, and Orexin
A1  - Nestler, Eric J.
A1  - Hyman, Steven E.
A1  - Holtzman, David M.
A1  - Malenka, Robert C.
Y1  - 2015
N1  - 
T2  - Molecular Neuropharmacology: A Foundation for Clinical Neuroscience, 3e
AB  - The  monoamine  neurotransmitters  (dopamine  [DA],  norepinephrine  [NE],  epinephrine,  serotonin,  and  histamine),  the  related  small  molecule  neurotransmitter,  acetylcholine  (ACh),  and  the  neuropeptides,  orexin  A  and  B,  have  an  unusual  but  functionally  significant  organization  in  the  brain.  Their  cell  bodies  are  restricted  to  a  small  number  of  nuclei  in  the  brainstem,  hypothalamus,  and  basal  forebrain,  but  their  axons  project  widely  throughout  the  central  nervous  system.  This  widely  projecting  organization  permits  each  of  these  neurotransmitters  to  modulate  activity  in  diverse  circuits,  sometimes  in  a  coordinated  fashion.For  example,  these  systems  play  critical  roles  in  sleep,  arousal,  and  attention,  and  in  survival  responses  to  relevant  stimuli.Widely  projecting  DA  neurons  have  their  cell  bodies  in  the  midbrain,  within  the  substantia  nigra  pars  compacta  and  the  ventral  tegmental  area.  DA  is  also  produced  by  neurons  in  the  arcuate  nucleus  of  the  hypothalamus,  and  by  local  circuit  neurons  in  the  retina.  Midbrain  DA  neurons  project  widely  to  the  forebrain  and  influence  motivation,  motor  behavior,  and  multiple  forms  of  memory.  DA  released  from  the  hypothalamus  suppresses  synthesis  and  release  of  prolactin  by  the  anterior  pituitary.NE  is  synthesized  in  nuclei  within  the  medulla  and  pons,  the  most  prominent  of  which  is  the  locus  ceruleus  (LC).  The  LC  provides  virtually  all  of  the  NE  to  the  cerebral  cortex.  NE  regulates  arousal,  attention,  vigilance,  and  memory.  Descending  NE  fibers  modulate  afferent  pain  signals.Serotonin  (5HT  or  5-hydroxytryptamine)  is  synthesized  by  neurons  within  the  raphe  nuclei  of  the  midbrain.  Their  axons  project  very  widely  in  the  brain  to  influence  diverse  circuits  involved  in  arousal,  sensory  processing,  mood,  and  emotions.ACh  is  the  neurotransmitter  at  the  neuromuscular  junction  (nerve–muscle  synapses).  In  the  brain  it  is  produced  by  widely  projecting  neurons  with  cell  bodies  in  the  brainstem  and  in  the  basal  forebrain  that  project  to  the  cerebral  cortex  and  hippocampus.  It  is  also  produced  by  interneurons  in  the  striatum.  ACh  in  the  forebrain  influences  many  processes  including  motivation,  learning,  and  memory.Histamine  is  produced  by  neurons  in  the  tuberomammillary  nucleus  that  lies  within  the  posterior  hypothalamus.  These  neurons  project  throughout  the  brain  to  regulate  arousal.  Inactivity  of  histamine  neurons  promotes  sleep.  Peripherally,  histamine  in  the  stomach  promotes  secretion  of  gastric  acid  via  H2  receptors;  histamine  released  from  mast  cells  is  involved  in  allergic  responses  mediated  via  H1  receptors.Orexin  A  and  B  (also  known  as  hypocretin  1  and  2)  are  related  neuropeptides  that  regulate  sleep  and  wakefulness  by  interacting  with  monoaminergic  and  cholinergic  neurons  that  in  turn  regulate  arousal,  emotion,  motivation,  and  feeding.  Orexin  neurons  have  cell  bodies  in  the  lateral  hypothalamus,  and  project  widely  throughout  the  brain.  Among  the  major  recipients  of  orexinergic  projections  are  the  LC,  a  source  of  NE,  and  the  tuberomammillary  nucleus  of  the  hypothalamus,  the  source  of  histamine.All  receptors  for  DA,  NE,  and  histamine  and  12  of  the  13  5HT  receptors  are  G  protein–coupled  receptors.  The  5HT3  receptor  is  a  ligand-gated  ion  channel.  ACh  receptors  are  divided  into  two  major  classes:  nicotinic  receptors,  which  are  ligand-gated  ion  channels,  and  muscarinic  receptors,  which  are  G  protein–coupled  receptors.  Like  most  neuropeptide  receptors,  both  orexin  receptors,  OX1  and  OX2  ...
SN  - 
PB  - McGraw-Hill Education
CY  - New York, NY
Y2  - 2024/04/19
UR  - accessbiomedicalscience.mhmedical.com/content.aspx?aid=1105915674
ER  -