Abstract
Potassium channels are key determinants of neuronal excitability. We recently identified KChIPs as a family of calcium binding proteins that coassociate and colocalize with Kv4 family potassium channels in mammalian brain (An et al. [2000] Nature 403:553). Here, we used light microscopic immunohistochemistry and multilabel immunofluorescence labeling, together with transmission electron microscopic immunohistochemistry, to examine the subcellular distribution of KChIPs and Kv4 channels in adult rat cerebellum. Light microscopic immunohistochemistry was performed on 40-μm free-floating sections using a diaminobenzidine labeling procedure. Multilabel immunofluorescence staining was performed on free-floating sections and on 1-μm ultrathin cryosections. Electron microscopic immunohistochemistry was performed using an immunoperoxidase pre-embedding labeling procedure. By light microscopy, immunoperoxidase labeling showed that Kv4.2, Kv4.3, and KChIPs 1, 3, and 4 (but not KChIP2) were expressed at high levels in cerebellar granule cells (GCs). Kv4.2 and KChIP1 were highly expressed in GCs in rostral cerebellum, whereas Kv4.3 was more highly expressed in GCs in caudal cerebellum. Immunofluorescence labeling revealed that KChIP1 and Kv4.2 are concentrated in somata of cerebellar granule cells and in synaptic glomeruli that surround synaptophysin-positive mossy fiber axon terminals. Electron microscopic analysis revealed that KChIP1 and Kv4.2 immunoreactivity is concentrated along the plasma membrane of cerebellar granule cell somata and dendrites. In synaptic glomeruli, KChIP1 and Kv4.2 immunoreactivity is concentrated along the granule cell dendritic membrane, but is not concentrated at postsynaptic densities. Taken together, these data suggest that A-type potassium channels containing Kv4.2 and KChIP1, and perhaps also KChIP3 and 4, play a critical role in regulating postsynaptic excitability at the cerebellar mossy-fiber/ granule cell synapse.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 144-155 |
| Number of pages | 12 |
| Journal | Journal of Comparative Neurology |
| Volume | 484 |
| Issue number | 2 |
| DOIs | |
| State | Published - Apr 4 2005 |
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Keywords
- A current
- Cerebellum
- Dendrite
- Excitability
- Shal
- Synaptic plasticity
ASJC Scopus subject areas
- Neuroscience(all)
Cite this
Light and electron microscopic analysis of KChIP and Kv4 localization in rat cerebellar granule cells. / Strassle, Brian W.; Menegola, Milena; Rhodes, Kenneth J.; Trimmer, James.
In: Journal of Comparative Neurology, Vol. 484, No. 2, 04.04.2005, p. 144-155.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Light and electron microscopic analysis of KChIP and Kv4 localization in rat cerebellar granule cells
AU - Strassle, Brian W.
AU - Menegola, Milena
AU - Rhodes, Kenneth J.
AU - Trimmer, James
PY - 2005/4/4
Y1 - 2005/4/4
N2 - Potassium channels are key determinants of neuronal excitability. We recently identified KChIPs as a family of calcium binding proteins that coassociate and colocalize with Kv4 family potassium channels in mammalian brain (An et al. [2000] Nature 403:553). Here, we used light microscopic immunohistochemistry and multilabel immunofluorescence labeling, together with transmission electron microscopic immunohistochemistry, to examine the subcellular distribution of KChIPs and Kv4 channels in adult rat cerebellum. Light microscopic immunohistochemistry was performed on 40-μm free-floating sections using a diaminobenzidine labeling procedure. Multilabel immunofluorescence staining was performed on free-floating sections and on 1-μm ultrathin cryosections. Electron microscopic immunohistochemistry was performed using an immunoperoxidase pre-embedding labeling procedure. By light microscopy, immunoperoxidase labeling showed that Kv4.2, Kv4.3, and KChIPs 1, 3, and 4 (but not KChIP2) were expressed at high levels in cerebellar granule cells (GCs). Kv4.2 and KChIP1 were highly expressed in GCs in rostral cerebellum, whereas Kv4.3 was more highly expressed in GCs in caudal cerebellum. Immunofluorescence labeling revealed that KChIP1 and Kv4.2 are concentrated in somata of cerebellar granule cells and in synaptic glomeruli that surround synaptophysin-positive mossy fiber axon terminals. Electron microscopic analysis revealed that KChIP1 and Kv4.2 immunoreactivity is concentrated along the plasma membrane of cerebellar granule cell somata and dendrites. In synaptic glomeruli, KChIP1 and Kv4.2 immunoreactivity is concentrated along the granule cell dendritic membrane, but is not concentrated at postsynaptic densities. Taken together, these data suggest that A-type potassium channels containing Kv4.2 and KChIP1, and perhaps also KChIP3 and 4, play a critical role in regulating postsynaptic excitability at the cerebellar mossy-fiber/ granule cell synapse.
AB - Potassium channels are key determinants of neuronal excitability. We recently identified KChIPs as a family of calcium binding proteins that coassociate and colocalize with Kv4 family potassium channels in mammalian brain (An et al. [2000] Nature 403:553). Here, we used light microscopic immunohistochemistry and multilabel immunofluorescence labeling, together with transmission electron microscopic immunohistochemistry, to examine the subcellular distribution of KChIPs and Kv4 channels in adult rat cerebellum. Light microscopic immunohistochemistry was performed on 40-μm free-floating sections using a diaminobenzidine labeling procedure. Multilabel immunofluorescence staining was performed on free-floating sections and on 1-μm ultrathin cryosections. Electron microscopic immunohistochemistry was performed using an immunoperoxidase pre-embedding labeling procedure. By light microscopy, immunoperoxidase labeling showed that Kv4.2, Kv4.3, and KChIPs 1, 3, and 4 (but not KChIP2) were expressed at high levels in cerebellar granule cells (GCs). Kv4.2 and KChIP1 were highly expressed in GCs in rostral cerebellum, whereas Kv4.3 was more highly expressed in GCs in caudal cerebellum. Immunofluorescence labeling revealed that KChIP1 and Kv4.2 are concentrated in somata of cerebellar granule cells and in synaptic glomeruli that surround synaptophysin-positive mossy fiber axon terminals. Electron microscopic analysis revealed that KChIP1 and Kv4.2 immunoreactivity is concentrated along the plasma membrane of cerebellar granule cell somata and dendrites. In synaptic glomeruli, KChIP1 and Kv4.2 immunoreactivity is concentrated along the granule cell dendritic membrane, but is not concentrated at postsynaptic densities. Taken together, these data suggest that A-type potassium channels containing Kv4.2 and KChIP1, and perhaps also KChIP3 and 4, play a critical role in regulating postsynaptic excitability at the cerebellar mossy-fiber/ granule cell synapse.
KW - A current
KW - Cerebellum
KW - Dendrite
KW - Excitability
KW - Shal
KW - Synaptic plasticity
UR - http://www.scopus.com/inward/record.url?scp=14644440566&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=14644440566&partnerID=8YFLogxK
U2 - 10.1002/cne.20443
DO - 10.1002/cne.20443
M3 - Article
C2 - 15736227
AN - SCOPUS:14644440566
VL - 484
SP - 144
EP - 155
JO - Journal of Comparative Neurology
JF - Journal of Comparative Neurology
SN - 0021-9967
IS - 2
ER -