scispace - formally typeset
Search or ask a question
Topic

GABAergic

About: GABAergic is a research topic. Over the lifetime, 9595 publications have been published within this topic receiving 473568 citations.


Papers
More filters
Journal ArticleDOI
TL;DR: The results demonstrate that the dopaminergic cell population of the striatum responds to dopamine denervation by increasing in number, apparently to compensate for loss of extrinsic dopaminaergic innervation.
Abstract: Intrinsic, striatal tyrosine hydroxylase-immunoreactive (TH-i) cells have received little consideration. In this study we have characterized these neurons and their regulatory response to nigrostriatal dopaminergic deafferentation. TH-i cells were observed in the striatum of both control and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated monkeys; TH-i cell counts, however, were 3.5-fold higher in the striatum of MPTP-lesioned monkeys. To establish the dopaminergic nature of the TH-i cells, sections were double-labeled with antibodies to dopamine transporter (DAT). Immunofluorescence studies demonstrated that nearly all TH-i cells were double-labeled with DAT, suggesting that they contain the machinery to be functional dopaminergic neurons. Two types of TH-i cells were identified in the striatum: small, aspiny, bipolar cells with varicose dendrites and larger spiny, multipolar cells. The aspiny cells, which were more prevalent, corresponded morphologically to the GABAergic interneurons of the striatum. Double-label immunofluorescence studies using antibodies to TH and glutamate decarboxylase (GAD67), the synthetic enzyme for GABA, showed that 99% of the TH-i cells were GAD67-positive. Very few (

241 citations

Journal ArticleDOI
TL;DR: After neuronal trauma, GABA exerted a novel and opposite effect, depolarizing neurons and increasing intracellular Ca2+.
Abstract: GABA is the dominant inhibitory neurotransmitter in the CNS. By opening Cl − channels, GABA generally hyperpolarizes the membrane potential, decreases neuronal activity, and reduces intracellular Ca 2+ of mature neurons. In the present experiment, we show that after neuronal trauma, GABA, both synaptically released and exogenously applied, exerted a novel and opposite effect, depolarizing neurons and increasing intracellular Ca 2+ . Different types of trauma that were effective included neurite transection, replating, osmotic imbalance, and excess heat. The depolarizing actions of GABA after trauma increased Ca 2+ levels up to fourfold in some neurons, occurred in more than half of the severely injured neurons, and was long lasting (>1 week). The mechanism for the reversed action of GABA appears to be a depolarized Cl − reversal potential that results in outward rather than inward movement of Cl − , as revealed by gramicidin-perforated whole-cell patch-clamp recording. The consequent depolarization and resultant activation of the nimodipine sensitive L- and conotoxin-sensitive N-type voltage-activated Ca 2+ channel allows extracellular Ca 2+ to enter the neuron. The long-lasting capacity to raise Ca 2+ may give GABA a greater role during recovery from trauma in modulating gene expression, and directing and enhancing outgrowth of regenerating neurites. On the negative side, by its depolarizing actions, GABA could increase neuronal damage by raising cytosolic Ca 2+ levels in injured cells. Furthermore, the excitatory actions of GABA after neuronal injury may contribute to maladaptive signal transmission in affected GABAergic brain circuits.

241 citations

Journal ArticleDOI
Yan Zhu1, Hua Shun Li1, Lijuan Zhou1, Jane Y. Wu1, Yi Rao1 
01 Jul 1999-Neuron
TL;DR: It is found that the ventricular zone of the LGE is repulsive to GABAergic neuronal migration, and the secreted protein Slit is a chemorepellent guiding the migratory direction of GABAergic neurons, and blockade of endogenous Slit signaling inhibits the repulsive activity in the VZ.

241 citations

Journal Article
TL;DR: In this article, the authors characterized the dopaminergic nature of striatal tyrosine hydroxylase-immunoreactive (TH-i) cells and their regulatory response to nigrostriatal deafferentation.
Abstract: Intrinsic, striatal tyrosine hydroxylase-immunoreactive (TH-i) cells have received little consideration. In this study we have characterized these neurons and their regulatory response to nigrostriatal dopaminergic deafferentation. TH-i cells were observed in the striatum of both control and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated monkeys; TH-i cell counts, however, were 3.5-fold higher in the striatum of MPTP-lesioned monkeys. To establish the dopaminergic nature of the TH-i cells, sections were double-labeled with antibodies to dopamine transporter (DAT). Immunofluorescence studies demonstrated that nearly all TH-i cells were double-labeled with DAT, suggesting that they contain the machinery to be functional dopaminergic neurons. Two types of TH-i cells were identified in the striatum: small, aspiny, bipolar cells with varicose dendrites and larger spiny, multipolar cells. The aspiny cells, which were more prevalent, corresponded morphologically to the GABAergic interneurons of the striatum. Double-label immunofluorescence studies using antibodies to TH and glutamate decarboxylase (GAD67), the synthetic enzyme for GABA, showed that 99% of the TH-i cells were GAD67-positive. Very few (

241 citations

Journal ArticleDOI
TL;DR: The results suggest that some OB interneurons are derived from progenitors outside the LGE and that precursors expressing what has classically been considered a pallial transcription factor generate GABAergic interneeurons.
Abstract: The subventricular zone (SVZ) of the postnatal brain continuously generates olfactory bulb (OB) interneurons. We show that calretinin+, calbindin+, and dopaminergic (TH+) periglomerular OB interneurons correspond to distinct subtypes of GABAergic cells; all were produced in the postnatal mouse brain, but they matured and were eliminated at different rates. The embryonic lateral ganglionic eminence (LGE) is thought to be the site of origin of postnatal SVZ neural progenitors. Consistently, grafts of the embryonic LGE into the adult brain SVZ generated many OB interneurons, including TH+ and calbindin+ periglomerular interneurons. However, calretinin+ cells were not produced from these LGE grafts. Surprisingly, pallial and septal embryonic progenitors transplanted into the adult brain SVZ also resulted in the generation of OB interneurons, including calretinin+ cells. A subset of Dlx2+ OB interneurons was derived from cells expressing Emx1, a transcription factor largely restricted to the pallium during development. Emx1 lineage-derived cells contributed a substantial portion of GABAergic cells in the OB, including calretinin+ interneurons. This is in contrast to cortex, in which Emx1 lineage-derived cells do not differentiate into GABAergic neurons. Our results suggest that some OB interneurons are derived from progenitors outside the LGE and that precursors expressing what has classically been considered a pallial transcription factor generate GABAergic interneurons.

241 citations


Network Information
Related Topics (5)
Hippocampal formation
30.6K papers, 1.7M citations
95% related
Synaptic plasticity
19.3K papers, 1.3M citations
95% related
Glutamate receptor
33.5K papers, 1.8M citations
95% related
Dopaminergic
29K papers, 1.4M citations
94% related
Hippocampus
34.9K papers, 1.9M citations
93% related
Performance
Metrics
No. of papers in the topic in previous years
YearPapers
2023371
2022749
2021341
2020320
2019301
2018297