title: Increased expression of TRPV1 in the cortex and hippocampus from patients with mesial temporal lobe epilepsy.
abstract: Transient receptor potential vanilloid type-1 (TRPV1) is a ligand-gated nonselective cation channel that has been well characterized in peripheral pain pathway. Recent evidence from animal models of temporal lobe epilepsy (TLE) has supported the important role of TRPV1 in epileptogenesis. In this study, we investigated the expression and cellular distribution of TRPV1 in the temporal cortex (CTX) and hippocampus (HPC) from 26 patients with mesial TLE (MTLE) compared with 12 histologically normal samples. Reverse transcription-PCR and Western blotting revealed up-regulated mRNA and protein levels of TRPV1 in the MTLE group versus the control group. Immunohistochemistry data demonstrated that TRPV1 was mainly distributed in the cell bodies and dendrites of neurons. Double-labeled immunofluorescence further revealed that TRPV1 was localized on NeuN-positive neurons and GFAP-positive astrocytes, but not on HLA-positive microglia. In addition, its co-localization with glutamate and gamma-aminobutyric acid (GABA) indicated that TRPV1 was distributed on both glutamatergic and GABAergic neurons. Moreover, nerve growth factor, a sensitizing factor for TRPV1, was showed a higher expression pattern in MTLE patients. Taken together, our findings suggest that the overexpression and distribution patterns of TRPV1 might be involved in the pathogenesis and epileptogenesis of human MTLE.
authors.affiliation: Department of Neurosurgery, Xinqiao Hospital, Third Military Medical University, 2-V Xinqiao Street, Chongqing 400037, China.
authors.forename: Fei-Ji
authors.initials: FJ
authors.lastname: Sun
authors.forename: Wei
authors.initials: W
authors.lastname: Guo
authors.forename: Da-Hai
authors.initials: DH
authors.lastname: Zheng
authors.forename: Chun-Qing
authors.initials: CQ
authors.lastname: Zhang
authors.forename: Song
authors.initials: S
authors.lastname: Li
authors.forename: Shi-Yong
authors.initials: SY
authors.lastname: Liu
authors.forename: Qing
authors.initials: Q
authors.lastname: Yin
authors.forename: Hui
authors.initials: H
authors.lastname: Yang
authors.forename: Hai-Feng
authors.initials: HF
authors.lastname: Shu
mesh_terms: D000293:Adolescent; D000328:Adult; D001253:Astrocytes / Q000378:metabolism; D016022:Case-Control Studies; D002540:Cerebral Cortex / Q000378:metabolism* / Q000473:pathology; D003712:Dendrites / Q000378:metabolism; D004833:Epilepsy, Temporal Lobe / Q000151:congenital* / Q000175:diagnosis / Q000235:genetics; D005260:Female; D059330:GABAergic Neurons / Q000378:metabolism; D018698:Glutamic Acid / Q000378:metabolism; D006624:Hippocampus / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D008297:Male; D017628:Microglia / Q000378:metabolism; D020932:Nerve Growth Factor / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000096:biosynthesis; D050916:TRPV Cation Channels / Q000235:genetics* / Q000378:metabolism; D015854:Up-Regulation; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
chemical_list: D012333:RNA, Messenger; D050916:TRPV Cation Channels; C494482:TRPV1 protein, human; D018698:Glutamic Acid; D005680:gamma-Aminobutyric Acid; D020932:Nerve Growth Factor