Electrophysiological, morphological, and topological properties of two histochemically distinct subpopulations of cerebellar unipolar brush cells.
Electrophysiological, morphological, and topological properties of two histochemically distinct subpopulations of cerebellar unipolar brush cells.
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DOI：
10.1007/s12311-012-0380-8
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发表时间：
2012-12
期刊：
影响因子：
3.5
通讯作者：
Martina, Marco
中科院分区：
文献类型：
--
作者：
Kim, Jin-Ah;Sekerkova, Gabriella;Mugnaini, Enrico;Martina, Marco
Unipolar brush cells (UBCs) are excitatory cerebellar granular layer interneurons whose brush-like dendrites receive one-to-one mossy fiber inputs. Subclasses of UBCs differ primarily by expressing metabotropic glutamate receptor (mGluR) 1α or calretinin. We used GENSAT Tg(Grp-EGFP) BAC-transgenic mice, which selectively express EGFP in mGluR1α-positive UBCs to compare the functional properties of the two subclasses. Compared to EGFP-negative UBCs, which include the calretinin-positive cells, EGFP-positive UBCs had smaller somata (diameter 18 vs. 21 μm), lower specific membrane resistance (6.4 vs.13.7 KΩ*cm2), were less prone to intrinsic firing and showed more irregular firing (in cell-attached ~49% were firing vs. ~88%, and the CV was 0.53 vs. 0.32 for EGFP-negative cells). Some of these differences are attributable to higher density of background K+ currents in EGFP-positive cells (at −120 mV the barium-sensitive current was 94 pA, vs 37 pA in EGFP-negative cells); Ih, on the contrary, was more abundantly expressed in EGFP-negative cells (at −140 mV it was −122 pA vs. −54 pA in EGFP-positive neurons); furthermore, while group II mGluR modulation of the background potassium current in EGFP-negative UBCs was maintained after intracellular dialysis, mGluR modulation in EGFP-positive UBCs was lost in whole cell recordings. Finally, cell-attached firing was reversibly abolished by the GABAB activation in EGFP-positive, but not in EGFP-negative UBCs. Immunohistochemistry showed that EGFP-negative UBCs express GIRK2 at high density, while mGluR1 UBCs are GIRK2-negative, suggesting that GIRK2 mediates the mGluR-sensitive current in EGFP-negative UBCs. These data suggest that the two subclasses perform different functions in the cerebellar microcircuits.
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影响因子：
30.8
作者：
PATIL, N;COX, DR;PETERSON, AS
通讯作者：
PETERSON, AS
影响因子：
5.5
作者：
Forti, Lia;Cesana, Elisabetta;D'Angelo, Egidio
通讯作者：
D'Angelo, Egidio
影响因子：
5.5
作者：
Dieudonné, S
通讯作者：
Dieudonné, S
影响因子：
2
作者：
Diño, MR;Perachio, AA;Mugnaini, E
通讯作者：
Mugnaini, E
DOI：
10.1023/a:1007072105919
发表时间：
1999-02-01
期刊：
JOURNAL OF NEUROCYTOLOGY
影响因子：
--
作者：
Diño, MR;Willard, FH;Mugnaini, E
通讯作者：
Mugnaini, E