Serotonin-immunoreactive CPT interneurons in Hermissenda: identification of sensory input and motor projections.
Serotonin-immunoreactive CPT interneurons in Hermissenda: identification of sensory input and motor projections.
复制标题
Hermissenda 中的血清素免疫反应性 CPT 中间神经元：感觉输入和运动投射的识别。
DOI：
10.1152/jn.00035.2006
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发表时间：
2006
影响因子：
2.5
通讯作者：
Crow,Terry
中科院分区：
文献类型：
--
作者：
Tian,Lian-Ming;Kawai,Ryo;Crow,Terry
脑胸膜神经节三胞胎（CPTs）的5-羟色胺免疫反应（5-HT-IR）神经元可能与其他蛇支软体动物的5-HT-IR神经元同源。在分离神经系统和半完整制剂的研究中，我们在研究了感觉输入和运动神经元投射后，结合使用免疫组织化学技术和路西弗黄荧光标记来识别5-HT-IR CPT神经元。在这里，我们发现鉴定的5-HT-IR CPT中间神经元接受来自机械感受器和光感受器的感觉输入。在具有完整踏板神经P1和P2的半完整的制备中，用标定的von Frey毛对足中部或尾部区域进行皮肤刺激，可以从鉴定的CPT中间神经元中记录到尖峰。眼睛的光照引起了一个小的复杂兴奋性突触后电位（EPSP），并导致CPT中间神经元的尖峰放电适度增加。路西法黄标记神经元的免疫染色显示CPT中间神经元向对侧足神经节投射轴突过程。外源电流下CPT中间神经元的去极化诱发了EPSPs和从确定的VP2踏板神经元记录的峰值，运动神经元先前被证明引起前足的运动。外源性电流刺激半完整制备的CPT中间神经元引起前足运动，但不促进纤毛活动或唤起已鉴定的VP1纤毛运动神经元中记录的psp。我们的研究结果表明，CPT神经元是多感觉中间神经元，有助于反射性足部收缩。
Serotonin immunoreactive (5-HT-IR) neurons identified as cerebropleural ganglion triplets (CPTs) inHermissendamay be homologues of 5-HT-IR neurons identified in other opisthobranch molluscs. In studies of isolated nervous systems and semi-intact preparations we used a combination of immunohistochemical techniques and fluorescent labeling with Lucifer yellow to identify 5-HT-IR CPT neurons after investigating sensory inputs and motor neuron projections. Here we show that identified 5-HT-IR CPT interneurons receive sensory input from mechanoreceptors and photoreceptors. In semi-intact preparations with intact pedal nerves P1 and P2, cutaneous stimulation of the middle or tail regions of the foot with calibrated von Frey hairs elicited spikes recorded from identified CPT interneurons. Illumination of the eyes evoked a small complex excitatory postsynaptic potential (EPSP) and resulted in a modest increase in the spike discharge of CPT interneurons. Immunostaining of Lucifer yellow–labeled neurons revealed that CPT interneurons projected an axonal process to the contralateral pedal ganglion. Depolarization of CPT interneurons with extrinsic current evoked EPSPs and spikes recorded from identified VP2 pedal neurons, motor neurons previously shown to elicit movement of the anterior foot. Extrinsic current stimulation of CPT interneurons in semi-intact preparations evoked movement of the anterior foot but did not facilitate ciliary activity or evoke PSPs recorded in identified VP1 ciliary motor neurons. Our results show that CPT neurons are polysensory interneurons that contribute to reflexive foot contractions inHermissenda.