脑源性多器官功能障碍综合征模型延髓内脏带c-fos蛋白表达变化研究

Study on c-fos protein expression in the medullary visceral zone of a model with cerebrogenic multiple organ dysfunction syndrome

目的研究脑出血致多器官功能障碍综合征模型延髓内脏带孤束核、迷走神经背核c-fos蛋白表达的变化规律,探讨延髓内脏带在脑源性多器官功能障碍综合征的应激调节作用。方法(1)于大鼠尾状核内注射Ⅶ型胶原酶(0.8U)建立脑出血模型。54只Wistar大鼠被随机分为正常对照组,假手术组及脑出血组(根据出血时间的不同又分为4、8、12、24、36、48h和72h等7个亚组)。(2)应用免疫组织化学ABC法观察脑出血后延髓内脏带内孤束核、迷走神经背核各时限c-fos蛋白的表达变化规律。结果正常对照组和假手术组大鼠延髓内脏带内孤束核、迷走神经背核的c-fos蛋白阳性表达极少;脑出血组大鼠孤束核、迷走神经背核c-fos蛋白阳性神经元呈密集表达,于脑出血后24～36h达高峰,其中孤束核在24h的表达密度为(49.58±12.61)μm2,36h为(64.32±15.14)μm2,与正常对照组及假手术组相比差异有显著性意义(均P<0.01);迷走神经背核在此两个时限的表达密度分别为(40.74±10.62)μm2,(50.62±12.31)μm2,差异亦有显著性意义(均P<0.01);至72h仍有阳性表达(P<0.05)。结论孤束核、迷走神经背核c-fos蛋白的阳性表达提示,延髓内脏带是脑源性多器官功能障碍综合征的应激调节中枢之一。

Objective To study the changes of c-fos protein expression in the solitary nucleus and dorsal nucleus of vagus nerve in medullary visceral zone （MVZ） of cerebral hemorrhage induced multiple organ dysfunction syndrome model and explore the possible stress regulation mechanism of MVZ in the cerebrogenic multiple organ dysfunction syndrome （CMODS）. Methods 1） Cerebral hemorrhage was induced by injecting 0.8 U collagenase VH into the caudate nucleus of rats. A total of 54 Wistar rats were randomly divid- ed into 9 groups ie. normal control group, sham-operation group and 7 hemorrhage groups including at 4, 8, 12, 24, 36, 48 and 72h seven time points. 2） The expression of c-fos protein in the solitary nucleus and dorsal nucleus in MVZ of vagus nerve were measured by immunohistochemistry （ABC）. Results A few of positive c-fos protein expression in the solitary nucleus and dorsal nucleus of vagus nerve of MVZ was found in normal control and sham-operation group. The positive c-fos neurons were densely expressed in the solitary nucleus and dorsal nucleus of vagus nerve in cerebral hemorrhage group, the peak of c-fos protein expression in the MVZ was reached at 24-36 h after hemorrhage. The expression density in the solitary nucleus at 24h was （49.58＋ 12.61 ） p.m2 and 36 h was （64.32＋ 15.14） Is.mz, with significant difference comparing to the normal con- tral group and sham-operation group （P〈 0.01）; in dorsal nucleus of vagus nerve was （40.74±10.62）μm^2, and （50.62±12.31）μm^2 at 24 h and 36 h respectively after hemorrhage with significant difference comparing to the normal control group and sham-operation group （P〈 0.01）; c-fos-like neurons can also be observed at 72 h after hemorrhage. Conclusion The positive c-fos protein expressions in the solitary nucleus and dorsal nucleus of vagus nerve demonstrate that MVZ is one of the stress regulation center in CMODS.