Cognitive, Behavioral, and Systems NeuroscienceResearch PaperIn vivo voltammetric monitoring of catecholamine release in subterritories of the nucleus accumbens shell
Section snippets
Animals
Adult male Sprague–Dawley rats (320–400 g) were purchased from Charles Rivers (Wilmington, MA, USA) and housed in temperature and humidity controlled rooms with ad libitum food and water with a 12/12 h light/dark cycle. All procedures for handling and caring for the laboratory animals were in accordance with the NIH Guide for Care and Use of Laboratory Animals and were approved by the Institutional Animal Care and Use Committee of the University of North Carolina at Chapel Hill.
Surgery
Rats were
Catecholamine content of the rostral and caudal NAc shell
The rostral and caudal NAc shell were dissected from fresh brains and their catecholamine content determined by HPLC (Table 1). The dopamine tissue content in the rostral and caudal NAc regions was not significantly different (t=0.99, df =25, P=0.33). Dopamine was a major catecholamine in the rostral NAc shell. Only a very low amount of norepinephrine was found (norepinephrine was present in 1 of 15 samples from five rats), but both dopamine and norepinephrine were present in significant
Discussion
Here, we examined the evoked release of catecholamines in two NAc sub regions with FSCV. The sensor employed, the carbon-fiber microelectrode, has micron dimensions allowing investigation of these two sub regions that are only separated by ∼800 μm. Catecholamine release was evoked by either stimulation of the MFB, a major ascending pathway that contains both dopaminergic and noradrenergic neurons (Ungerstedt, 1971), or the VTA/SN region. Stimulation in the latter region activates dopamine cell
Conclusion
The present results show that norepinephrine is regulated in the caudal NAc shell by norepinephrine autoreceptors and uptake transporters. This result suggests that dopaminergic and noradrenergic transmission within the caudal NAc shell may play significantly different roles in regulating the behavioral and physiologic responses associated with drug abuse, physical stressors and other rewarding and aversive stimuli, compared to the rostral NAc shell.
Acknowledgments
We thank Khristy Fontillas for providing technical assistance and thank Richard B. Keithley and Dr. Nii Addy for supporting data analysis. This work was supported by NIH (NS 15841 to RMW and DA 17318 to RMC and RMW).
References (44)
- et al.
Correlation between behavior and extracellular dopamine levels in rat striatum: comparison of microdialysis and fast-scan cyclic voltammetry
Neurosci Lett
(2000) - et al.
Origin of noradrenergic afferents to the shell subregion of the nucleus accumbens: anterograde and retrograde tract-tracing studies in the rat
Brain Res
(1998) The role of dopamine in drug abuse viewed from the perspective of its role in motivation
Drug Alcohol Depend
(1995)- et al.
Short-acting cocaine and long-acting GBR-12909 both elicit rapid dopamine uptake inhibition following intravenous delivery
Neuroscience
(2008) - et al.
Simultaneous quantification of serotonin, dopamine and noradrenaline levels in single frontal cortex dialysates of freely-moving rats reveals a complex pattern of reciprocal auto- and heteroreceptor-mediated control of release
Neuroscience
(1998) - et al.
Sucrose sham feeding decreases accumbens norepinephrine in the rat
Physiol Behav
(2004) Dopamine reward circuitry: two projection systems from the ventral midbrain to the nucleus accumbens-olfactory tubercle complex
Brain Res Rev
(2007)- et al.
Multivariate concentration determination using principal component regression with residual analysis
TrAc Trends Anal Chem
(2009) - et al.
Real-time monitoring of endogenous noradrenaline release in rat brain slices using fast cyclic voltammetry: 1Characterisation of evoked noradrenaline efflux and uptake from nerve terminals in the bed nucleus of stria terminalis, pars ventralis
Brain Res
(1992) The projections of the ventral tegmental area and adjacent regions: a combined fluorescent retrograde tracer and immunofluorescence study in the rat
Brain Res Bull
(1982)