白明胶酶与囊性脑动脉瘤发病关系的研究

In situ localization of mRNA gelatinases in cerebral aneurysms

目的检测囊性脑动脉瘤及正常脑动脉标本中白明胶酶A，B及其组织抑制因子的mRNA。方法用地高辛标记的RNA探针与脑动脉瘤和正常脑动脉组织进行原位杂交。结果所有脑动脉瘤标本中均见白明胶酶BmRNA阳性杂交信号；在内膜，尤其是内弹力层断裂、消失部位，阳性杂交信号密集存在。得回归方程：y＝9．014＋0．963x，说明二者呈正相关。正常脑动脉标本中未发现白明胶酶BmRNA阳性杂交信号。在脑动脉瘤和正常脑动脉组织中未发现白明胶酶A及其组织抑制因子的mRNA的阳性杂交信号。结论白明胶酶B增多，可导致内弹力层断裂、消失，甚至动脉壁全层结构的破坏，从而进一步引发脑动脉瘤的形成。

Objective To explore the role of gelatinases A and B and their tissue inhibitors,TIMP-1 and TIMP-2, in the formation of cerebral aneurysm. Methods In situ hybridization with digoxigenin RNA probes localized cells responsible for gelatinases A and B, TIMP-1 and TIMP-2 mRNA production in histologic sections of aneurysmal (n =12), and normal (n = 6) cerebral arteries. Results The levels of geatinase B mRNA were found very high in cerebral aneurysms, especially in the site of internal elastic lamella. Gelatinase B mRNA was not found in normal cerebral arteries.Gelatinase A TIMP-1 and TIMP-2 mRNA were not found in both cerebral aneurysms and normal cerebral arteries. Conclusions Differential patterns of expression can be seen in situ, and tissue gelatinase B mRNA levels are elevaed in aneurysms, suggesting that gelatinase B maybe responsible for the destruction of internal elastic lamina or even all laminae of cerebral arteries, leading to cerebral aneurysms.