Hirakawa M, Kawata M
Department of Anatomy, Kyoto Prefectural University of Medicine, Japan.
J Hirnforsch. 1993;34(3):431-44.
c-Fos expression in the rat central nervous system following sciatic nerve section was compared using an immunohistochemical procedure with control skin-incisions. c-Fos-immunoreactive (IR) materials were localized in the nuclei of nerve cells, and these positive cells were most abundantly observed 120 min after the operation. In the spinal cord, c-Fos-IR cells were seen in the posterior horn on the operated, but not in the contralateral side. The anterior horn and the dorsal root ganglia did not contain c-Fos-IR cells. The experimental animals had the largest number of c-Fos-IR cells in the lumbosacral segments, especially in laminae I and II of L4 and L5 segments. The difference in the number of c-Fos-IR cells and IR intensity between the experimental and control animals was conspicuous in the lumbosacral segments, but there was no significant difference between them in the cervical and thoracic segments. In the brain, an apparent difference in positive cell distribution was not recognized between the experimental and control animals. c-Fos-IR cells were observed in various regions of the brain. A high concentration of positive cells was seen in the temporal cortex, the clastrum, the lateral septal nucleus (ventral part), the hypothalamic nuclei such as periventricular, suprachiasmatic, paraventricular, arcuate, dorsomedial and supramammillary nuclei, the paraventricular thalamic nucleus, the ventral lateral geniculate nucleus (magnocellular part), the pontine nuclei, the dorsal and dorsolateral tegmental nuclei, the parabrachial nucleus (Kölliker-Fuse nucleus), the locus coeruleus, and the nucleus of the solitary tract. Among them, the paraventricular and suprachiasmatic hypothalamic nuclei exhibited the most dense concentration of c-Fos-IR cells and intensity. These results indicate that the c-Fos expression in the brain is induced by transsynaptic stimulation. The findings that there was a clear difference in the distribution of c-Fos-IR cells and in intensity between the experimental and control animals in the lumbosacral segment of the spinal cord but not in the upper portion and the brain, suggested that there is poor discrimination of nociceptive information in the brain between stimulation by nerve section and skin-incision.
采用免疫组织化学方法，将坐骨神经切断后大鼠中枢神经系统中c-Fos的表达与对照皮肤切口进行比较。c-Fos免疫反应性（IR）物质定位于神经细胞核内，术后120分钟观察到这些阳性细胞数量最多。在脊髓中，c-Fos-IR细胞出现在手术侧的后角，而对侧未出现。前角和背根神经节不含c-Fos-IR细胞。实验动物在腰骶段c-Fos-IR细胞数量最多，尤其是在L4和L5节段的I层和II层。实验动物和对照动物之间，腰骶段c-Fos-IR细胞数量和IR强度存在明显差异，但在颈段和胸段无显著差异。在脑中，实验动物和对照动物之间未发现阳性细胞分布有明显差异。在脑的各个区域均观察到c-Fos-IR细胞。在颞叶皮质、屏状核、外侧隔核（腹侧部分）、下丘脑核如室周核、视交叉上核、室旁核、弓状核、背内侧核和乳头体上核、丘脑室旁核、腹侧外侧膝状核（大细胞部分）、脑桥核、背侧和背外侧被盖核、臂旁核（ Kölliker-Fuse核）、蓝斑核和孤束核中可见高浓度的阳性细胞。其中，室旁下丘脑核和视交叉上核的c-Fos-IR细胞浓度和强度最高。这些结果表明，脑中的c-Fos表达是由跨突触刺激诱导的。实验动物和对照动物在脊髓腰骶段c-Fos-IR细胞分布和强度存在明显差异，而在上部和脑中无差异，这一发现表明，在脑内，神经切断刺激和皮肤切口刺激之间对伤害性信息的辨别能力较差。
