PMID- 10704782
OWN - NLM
STAT- MEDLINE
DCOM- 20000324
LR  - 20190719
IS  - 0361-9230 (Print)
IS  - 0361-9230 (Linking)
VI  - 51
IP  - 4
DP  - 2000 Mar 1
TI  - Hippocampal norepinephrine-like voltammetric responses following infusion of 
      corticotropin-releasing factor into the locus coeruleus.
PG  - 319-26
AB  - Intracerebroventricular (i.c.v.) administration of corticotropin-releasing factor 
      (CRF) increases the activity of noradrenergic neurons in the locus coeruleus (LC) 
      assessed by electrophysiological and neurochemical studies. It has been suggested 
      that this effect of i.c.v. CRF is exerted directly on LC noradrenergic (LC-NE) 
      neurons. Infusion of CRF directly into the LC increases cortical and hippocampal 
      release of norepinephrine (NE) as indicated by in vivo microdialysis studies, but 
      the electrophysiological studies have shown both increases and decreases. The 
      present study used in vivo voltammetry to study changes in the extracellular 
      concentrations of NE in the rat hippocampus in response to infusion of CRF (100 
      ng) into the LC. When the infusion cannula was located in or very close to the 
      LC, the immediate response to CRF was a small decrease in the NE-like oxidation 
      current, followed by a robust increase after about 6-7 min. The oxidation current 
      reached a peak around 13 min and returned to baseline by about 30 min after CRF 
      infusion. By contrast with CRF, infusion of glutamate into the LC increased the 
      oxidation current with a delay of around 30 s and a peak within 90 s. The 
      responses to LC infusion of CRF in rats treated with DSP-4 to deplete hippocampal 
      NE were substantially smaller than those in untreated rats, suggesting that the 
      oxidation signals in untreated rats reflected changes in concentrations of NE. 
      The response to glutamate was markedly augmented by pretreatment with the NE 
      reuptake inhibitor, desmethylimipramine, suggesting that the observed responses 
      reflected changes in NE. Infusion of the same dose of CRF into brain structures 
      outside the LC did not elicit consistent changes in oxidation current in the 
      hippocampus. The time course of the responses to CRF is compatible with 
      previously reported electrophysiological responses of LC-NE neurons to CRF and 
      with neurochemical evidence indicating that CRF can affect the activity of LC-NE 
      neurons. The results indicate that CRF may act in or close to the LC to induce 
      release of hippocampal NE, but the delayed response to CRF compared with that to 
      glutamate, suggests that CRF does not directly activate LC-NE neurons.
FAU - Palamarchouk, V S
AU  - Palamarchouk VS
AD  - Department of Pharmacology and Therapeutics, Louisiana State University Medical 
      Center, Shreveport, LA 71130-3932, USA.
FAU - Zhang, J
AU  - Zhang J
FAU - Zhou, G
AU  - Zhou G
FAU - Swiergiel, A H
AU  - Swiergiel AH
FAU - Dunn, A J
AU  - Dunn AJ
LA  - eng
GR  - MH50947/MH/NIMH NIH HHS/United States
PT  - Journal Article
PT  - Research Support, U.S. Gov't, Non-P.H.S.
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - United States
TA  - Brain Res Bull
JT  - Brain research bulletin
JID - 7605818
RN  - 9015-71-8 (Corticotropin-Releasing Hormone)
RN  - X4W3ENH1CV (Norepinephrine)
SB  - IM
MH  - Animals
MH  - Corticotropin-Releasing Hormone/*pharmacology
MH  - Electrophysiology
MH  - Hippocampus/*metabolism
MH  - Injections
MH  - *Locus Coeruleus
MH  - Male
MH  - Microdialysis
MH  - Norepinephrine/*metabolism
MH  - Rats
MH  - Rats, Sprague-Dawley
EDAT- 2000/03/08 09:00
MHDA- 2000/04/01 09:00
CRDT- 2000/03/08 09:00
PHST- 2000/03/08 09:00 [pubmed]
PHST- 2000/04/01 09:00 [medline]
PHST- 2000/03/08 09:00 [entrez]
AID - S0361923099002415 [pii]
AID - 10.1016/s0361-9230(99)00241-5 [doi]
PST - ppublish
SO  - Brain Res Bull. 2000 Mar 1;51(4):319-26. doi: 10.1016/s0361-9230(99)00241-5.