Hyper-Formation of GABA and Glycine Co-Releasing Terminals in the Mouse Cerebellar Nuclei after Deprivation of GABAergic Inputs from Purkinje Cells.
Neuroscience
; 426: 88-100, 2020 02 01.
Article
em En
| MEDLINE
| ID: mdl-31846755
ABSTRACT
GABA and glycine are inhibitory neurotransmitters. However, the mechanisms underlying the formation of GABAergic and glycinergic synapses remain unclear. The influence of GABAergic input deprivation on inhibitory terminal formation was investigated using Purkinje cell (PC)-specific vesicular GABA transporter (VGAT) knockout (L7-VGAT) mice, in which GABA release from PCs diminishes in an age-dependent manner. We compared the late development of GABAergic and glycinergic terminals in the cerebellar nucleus (CN) between control and L7-VGAT mice. In the control CN, the density of glutamate decarboxylase (GAD)-positive dots remained unchanged between postnatal 2â¯months (P2M) and 13â¯months (P13M), whereas glycine transporter 2 (GlyT2)-positive dots increased in density during this time frame. No difference in the density of GlyT2-positive dots was observed between control and L7-VGAT mice at P2M, but the density was significantly higher in the L7-VGAT fastigial nuclei (FN) than the control FN at P13M. When VGAT was absent from PC terminals, GlyT2-positive dots included GAD and VGAT and formed synapses. These results indicated that GABAergic terminals were formed by P2M, glycinergic terminals were actively formed after P2M, and more glycinergic terminals were formed in the L7-VGAT FN than in the control FN, suggesting that the increased glycinergic terminals may derive from interneurons within the FN and may also release GABA. These results suggest that the deprivation of GABAergic inputs from PCs may accelerate the formation of co-releasing terminals derived from interneurons and that the inhibitory terminal numbers and types may be regulated by the quantity of functional GABAergic inputs.
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Texto completo:
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Células de Purkinje
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Sinapses
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Núcleos Cerebelares
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Neurotransmissores
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Ácido gama-Aminobutírico
Limite:
Animals
Idioma:
En
Ano de publicação:
2020
Tipo de documento:
Article