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Intranasal Administration of CNS Therapeutics to Awake Mice
Published on: April 8, 2013
Systemic administration of WIN 55,212-2 increases norepinephrine release in the rat frontal cortex
V C Oropeza1, M E Page, E J Van Bockstaele
1Department of Neurosurgery, Farber Institute for Neurosciences, Thomas Jefferson University, Philadelphia, PA 19107, USA. veronica.oropeza@jefferson.edu
Brain Research
|June 2, 2005
Summary
Cannabinoid agonists, like WIN 55,212-2, increase norepinephrine release in the rat frontal cortex. This effect is mediated by cannabinoid receptors and activates neurons in the locus coeruleus.
Area of Science:
- Neuroscience
- Pharmacology
Background:
- Cannabinoid receptors are widely distributed in the central nervous system and influence behavior.
- Norepinephrine is a key neurotransmitter involved in attention, arousal, and anxiety.
Purpose of the Study:
- To investigate the effect of a synthetic cannabinoid agonist, WIN 55,212-2, on norepinephrine efflux in the rat frontal cortex.
- To identify the specific neural pathways and cellular mechanisms involved in this process.
Main Methods:
- Systemic administration of WIN 55,212-2 to rats.
- Measurement of norepinephrine efflux in the frontal cortex.
- Immunocytochemical detection of c-Fos and tyrosine hydroxylase (TH) in the locus coeruleus (LC).
- Administration of cannabinoid receptor antagonist SR 141716A.
Main Results:
- WIN 55,212-2 dose-dependently increased norepinephrine release in the frontal cortex.
- WIN 55,212-2 increased c-Fos expression in TH-containing neurons in the LC.
- The cannabinoid receptor antagonist SR 141716A blocked both the norepinephrine release and the c-Fos expression induced by WIN 55,212-2.
Conclusions:
- Systemic cannabinoid agonists stimulate norepinephrine release in the frontal cortex by activating noradrenergic neurons in the LC.
- These findings suggest that cannabinoid-induced changes in attention, arousal, and anxiety may be partly mediated by this pathway.
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