猫体感皮质内脏伤害性感受神经元的染料偶联及缝隙连接

Study on dye-coupling and gap-junction with intracellular injection of neurobiotin to the visceral nociceptive neurons of somatosensory cortex in cats

利用在体实验探讨猫体感皮质的神经生物素的染料偶联现象及其细胞的连接方式 ,研究其存在电突触的可能性 ,为内脏伤害性感受神经元间存在神经微环路的推测提供实验资料。在 S 、S 区的内脏大神经代表区 ,用神经生物素标记内脏伤害性感受神经元的同时 ,观察单细胞注射而多重细胞标记即染料偶联现象。在标记成功的 52例中 ,共 1 5例 ( 2 8.8%)出现多种排列方式的神经生物素染色的色素偶联细胞 ,此情况在 S 区更为多见 ( 34.0 %)。提示其间可能存在缝隙连接 ,从而组成交互的环路联系 ,使相关神经元的活动呈现同步化 ,以介导复杂的痛觉反应活动。

With intracellular injection of neurobiotin in vivo , fifty two neurons were successfully labeled in somatosensory cortex of cats. Iontophoretic injection of the neurobiotin into single visceral nociceptive neurons of SⅠ and SⅡ areas resulted in the staining of more than one cell. Out of the 52 labeled cells, dye coupling was found in 15 cases in different cortical layers of SⅠ and SⅡ areas and often organized to vertical column. Most couplings were pyramidal pyramidal,a few of them were seen among non pyramidal cells. These findings suggest that the pattern of junctional connection among the coupling cells may be the gap junction which forms neurons network to intervene the same activity of painful sensation.