成年大鼠背根神经节电生理分类细胞的化学反应性和组织化学表型。
文章的细节
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引用
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Petruska JC, Napaporn J, Johnson RD, Cooper BY
成年大鼠背根神经节电生理分类细胞的化学反应性和组织化学表型。
神经科学。2002;115(1):15 - 30。
- PubMed ID
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12401318 (PubMed视图]
- 摘要
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从中等直径(35-45微米)的背根神经节神经元中获得全细胞贴片记录。利用电生理参数,我们能够将急性游离背根神经节细胞细分为三种统一的(5、6和9型)和一种混合的(8型)神经元。所有亚型(5、6、8和9型)均具有广泛的动作电位(7.0+/-0.2、5.2+/-0.4、7.3+/-0.5和6.0+/-0.4 ms)和超极化后异常长(112+/-9、178+/-19、124+/-31和204+/-33 ms)。长期以来,超极化已被其他实验室与机械不敏感(沉默)伤害感受器联系在一起[Djouhri等,J. Physiol. 513(1998) 857-872]。化学敏感性因细胞类别而异。5、8和9型细胞对辣椒素敏感(45+/-13、87+/-30和28+/-13 pA/pF;5 microM)组,而6型细胞对辣椒素不敏感。所有类型的细胞都表达asic样(酸敏感离子通道)阿米洛利敏感的质子激活电流,阈值为pH 6.8,峰值接近pH 5.0。所有中等大小的细胞都对ATP(50微米)敏感,并表现出“混合”形式的ATP门控电流[Burgard等人,J.神经生理学. 82 (1999)1590-1598;格拉布和埃文斯,欧洲。 J. Neurosci. 11 (1999) 149-154]. Immunohistochemistry performed on individual cells indicated the expression of both P2X(1) and P2X(3) subunits. Electrophysiologically defined classes were histochemically uniform. All types were examined for the presence of substance P (SP), calcitonin gene related peptide (CGRP) and binding of isolectin B4 (IB4). All subtypes expressed CGRP immunoreactivity. Types 5 and 8 co-expressed SP and CGRP immunoreactivity and also bound IB4. Subtypes 6 and 9 were positive for neurofilament m. It is likely that these cells represent major classes of myelinated and unmyelinated peptide expressing nociceptors.