Tanaka M, Takeda N, Senba E, Tohyama M, Kubo T, Matsunaga T
Department of Otolaryngology, Osaka University School of Medicine, Japan.
Brain Res. 1989 Dec 11;504(1):31-5. doi: 10.1016/0006-8993(89)91593-x.
The localization, origin and fine structure of nerve terminals immunoreactive for calcitonin gene-related peptide (CGRP) were examined in the vestibular end-organs of rats using immunocytochemistry. Many CGRP-like immunoreactive (CGRP-IR) fibers were observed in the vestibular sensory epithelial layer. By electronmicroscopy, CGRP-IR terminals were found to make synaptic contacts with the chalyces of the vestibular nerves terminating on type I cells. The origin of these vestibular CGRP-IR fibers was examined by a combination of a retrograde fiber tracing technique (using Fast blue) and immunocytochemistry. Injections of the tracer into the vestibular cistern, resulted in fast blue-labeled neurons bilaterally in the area dorsolateral to the genu of the facial nerve; these labeled neurons also contained CGRP. These findings indicate that CGRP-IR fibers originate bilaterally from the area dorsolateral to the genu of the facial nerve and that CGRP plays a modulatory role in the transmission of vestibular information from type I cells.
利用免疫细胞化学方法，对大鼠前庭终器中降钙素基因相关肽（CGRP）免疫反应阳性神经终末的定位、起源及精细结构进行了研究。在前庭感觉上皮层观察到许多CGRP样免疫反应（CGRP-IR）纤维。通过电子显微镜观察发现，CGRP-IR终末与终止于I型细胞的前庭神经壶腹形成突触联系。采用逆行纤维追踪技术（使用快蓝）和免疫细胞化学相结合的方法，研究了这些前庭CGRP-IR纤维的起源。将示踪剂注入前庭池后，在面神经膝部背外侧区域双侧出现快蓝标记的神经元；这些标记的神经元也含有CGRP。这些结果表明，CGRP-IR纤维双侧起源于面神经膝部背外侧区域，并且CGRP在前庭I型细胞信息传递中起调节作用。
