Inhibitory zinc-enriched terminals in the mouse cerebellum: double-immunohistochemistry for zinc transporter 3 and glutamate decarboxylase.
In the present study, we showed for the first time the presence of inhibitory zinc-enriched neuron terminals in the mouse cerebellar cortex by means of double-immunohistochemistry for zinc transporter 3 (ZnT3) and glutamate decarboxylase (GAD). The co-localization of ZnT3 and GAD in the cerebellar cortex was analyzed by confocal microscopy. Strong, punctuate ZnT3-immunoreactivity (Ir) was predominantly distributed in the granule cell layer, while GAD-Ir was seen throughout the cerebellar cortical layers. All of the ZnT3-immunoreactive structures were also immunopositive to GAD, but not vice versa. Based on size and position, these double-labeled elements were axonal terminals of the Golgi and basket cells, in the granule cell and molecular layers, respectively. Observations by electron microscopy revealed that ZnT3-immunoreactive terminals showed typical characteristics of the inhibitory synapses like the following: (1) presynaptic terminals containing flat vesicles; and (2) symmetrical synaptic contacts with dendritic elements. The present results indicate that a zinc-containing GABAergic system exists in the mouse cerebellar cortex.
Wang
Zhanyou
Z
Department of Anatomy and Cell biology, Goteborg University, Medicinaregatan 3-5, Box 420, SE-405 30 Goteborg, Sweden.
Danscher
Gorm
G
Kim
Yong Kuk
YK
Dahlstrom
Annica
A
Mook Jo
Seung
S
D000818:Animals; D002352:Carrier Proteins / Q000378:metabolism*; D002525:Cerebellar Cortex / Q000201:enzymology* / Q000648:ultrastructure; D005968:Glutamate Decarboxylase / Q000378:metabolism*; D007150:Immunohistochemistry; D007395:Interneurons / Q000201:enzymology / Q000648:ultrastructure; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008854:Microscopy, Electron; D009433:Neural Inhibition / Q000502:physiology*; D017729:Presynaptic Terminals / Q000201:enzymology* / Q000648:ultrastructure; D015032:Zinc / Q000378:metabolism*; D005680:gamma-Aminobutyric Acid / Q000378:metabolism*
D002352:Carrier Proteins; C017800:zinc-binding protein; D005680:gamma-Aminobutyric Acid; D005968:Glutamate Decarboxylase; D015032:Zinc