Liu L, Wang Y, Simon S A
Department of Neurobiology, Duke University Medical Center, Durham, NC 27710, USA Department of Anesthesiology, Duke University Medical Center, Durham, NC 27710, USA.
Pain. 1996 Jan;64(1):191-195. doi: 10.1016/0304-3959(94)00097-2.
Capsaicin is a pungent-tasting compound produced by plants in the Capsium family that activates a subset of primary afferent neurons associated with pain and thermoreception. Previous studies from dorsal root ganglion (DRGs) neurons suggest that many of capsaicin's physiological responses are a consequence of its activating a cation-selective current. To further characterize the responses to capsaicin whole-cell patch-clamp measurements were performed on rat DRGs to which 0.1-10 microM capsaicin was continuously applied. The capsaicin-activated currents exhibited marked variability in their thresholds, amplitude (to 15 nA), rates of desensitization, and the number of distinct maxima in the evoked current. Similar responses were found in rat trigeminal ganglion cells. The heterogeneity in the magnitude of the currents evoked by 0.1 microM capsaicin likely reflects different types of capsaicin-sensitive neurons; a result consistent with in vitro extracellular recordings from capsaicin-sensitive sensory afferents (Seno and Dray 1993).
辣椒素是辣椒属植物产生的一种具有辛辣味道的化合物，它能激活与疼痛和温度感受相关的一部分初级传入神经元。先前来自背根神经节（DRG）神经元的研究表明，辣椒素的许多生理反应是其激活阳离子选择性电流的结果。为了进一步表征对辣椒素的反应，对大鼠DRG进行了全细胞膜片钳测量，并持续施加0.1 - 10微摩尔的辣椒素。辣椒素激活的电流在阈值、幅度（高达15纳安）、脱敏速率以及诱发电流中不同最大值的数量方面表现出显著的变异性。在大鼠三叉神经节细胞中也发现了类似的反应。0.1微摩尔辣椒素诱发的电流大小的异质性可能反映了不同类型的辣椒素敏感神经元；这一结果与辣椒素敏感感觉传入纤维的体外细胞外记录结果一致（塞诺和德雷，1993年）。
