GABA and enkephalin projection from the nucleus accumbens and ventral pallidum to the ventral tegmental area

doi:10.1016/0306-4522(93)90048-K

Neuroscience

Volume 57, Issue 4, December 1993, Pages 1047-1060

https://doi.org/10.1016/0306-4522(93)90048-K Get rights and content

Abstract

GABAergic and enkephalinergic afferents to the ventral tegmental area were investigated in the rat using retrograde tracing techniques combined with in situ hybridization. Following iontophoretic deposit of Fluoro-Gold in the ventral tegmental area labeling in the forebrain was most dense in the shell of the nucleus accumbens, rostral ventromedial ventral pallidum and diagonal band of Broca. A smaller density was also observed in the lateral septum. In these forebrain regions, the portion of retrogradely labeled cells that contained mRNA for glutamate decarboxylase ranged from 25% to 50%, whereas only 5% to 15% were double-labeled for preproenkephalin mRNA. Cells double-labeled with either glutamate decarboxylase or preproenkephalin mRNA were most numerous in the lateral septum, shell of the nucleus accumbens, rostral ventral pallidum and diagonal band of Broca. Large Fluoro-Gold deposits which invaded the medial substantia nigra resulted in a significant number of retrogradely labeled cells in the core of the nucleus accumbens, and a portion of these neurons also contained mRNA for glutamate decarboxylase or preproenkephalin.

These data demonstrate the presence of GABAergic and enkephalinergic neurons projecting from the nucleus accumbens, ventral pallidum and diagonal band of Broca to the ventral tegmental area.

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GABA and enkephalin projection from the nucleus accumbens and ventral pallidum to the ventral tegmental area

Abstract

Neuropharmacology

Brain Res.

Neuron

Brain Res.

Brain Res.

Neuroscience

Neuroscience

Brain Res. Rev.

Neurosci. Lett.

Brain Res.

Brain Res. Bull.

Neuropharmacology

Neuroscience

Brain Res.

Brain Res.

Neuroscience

Brain Res.

Neuroscience

Opioid delta agonists and endogenous enkephalins induce different emotional reactivity than μ agonists after injection in the rat ventral tegmental area

Psychopharmacology

Excitotoxin lesions suggest an aspartatergic projection from rat medial prefrontal cortex to ventral tegmental area

Acta physiol. scand.

GABAA receptors containing α1 and β2 subunits are mainly localized on neurons in the ventral pallidum

Synapse

Evidence for the existence of monoamine-containing neurons in the central nervous system. I. Demonstration of monoamines in the cell bodies of brain stem neurons

Acta physiol. scand.

GABA_A receptors containing α₁ and β₂ subunits are mainly localized on neurons in the ventral pallidum