PKCγ免疫反应定位小鼠皮质脊髓束的实验研究

目的探讨显示皮质脊髓束在成年小鼠脑和脊髓中定位分布的简便有效方法。方法运用蛋白激酶Cγ（PKCγ）免疫组织化学染色法,观察成年ICR小鼠脑和脊髓中皮质脊髓束的定位和分布情况。结果PKCγ免疫阳性产物分布于大脑运动皮层第V层锥体细胞胞体和轴突中,锥体细胞的阳性纤维经内囊、中脑大脑脚底、脑桥基底部、下行至延髓锥体中。在延髓下段,PKCγ阳性纤维经锥体交叉后进入对侧脊髓灰质后联合背侧,形成背侧皮质脊髓束,在脊髓白质的后索腹侧深层下行,至骶髓3-4节段以下逐渐消失。在整个脊髓前索和外侧索中未见有PKCγ阳性纤维。结论PKCγ特异地表达于脊髓后索皮质脊髓束中,提示PKCγ免疫组织化学法是一种显示和观察皮质脊髓束精确定位的有效方法。

LOCALIZATION OF CORTICOSPINAL TRACT IN MICE BY USING PKCγ IMMUNOLOGICAL REACTION

Objective To find an effective method to localize the corticospinal tracts in brain and spinal cord of the adult mouse. Methods The localization and distribution of corticospinal tracts in brain and spinal cord of adult ICR mice were studied by using protein kinase CT （PKCγ） immunohistochemical staining. Results PKCγ immunoreactive products were distributed in cell body and axon of pyramid cells in the cerebral cortex, and the PKCγ-positive axons of pyramid cells passed through the internal capsule, cerebral peduncle of midbrain, basilar portion of pons, to the pyramid of medulla oblongata. At the lower part of medulla oblongata, most of the positive axons passed through the pyramidal decussation to the contralateral side, continued as the dorsal corticospinal tracts （dcsTs） . They （dcsTs） descended at the ventral part of posterior funiculus just dorsal to the gray commissure throughout most of the length of the spinal cord, and gradually disappeared down the 3-4 sacral spinal segments. The PKCγ positive axons were not seen in the lateral and anterior funiculi of the spinal cord. Conclusion PKCγ is expressed in the corticospinal tracts of posterior funiculus of mice, which suggests that the PKCγ immunohistochemistry is an effective method to reveal and visualize the localization of corticospinal tracts.