Liu Kang, Li Zhen, Wu Tao, Ding Suju
Department of Neurology, Changhai Hospital, Second Military Medical University, Shanghai 200433, China; E-Mails:
Int J Mol Sci. 2011 Feb 18;12(2):1222-31. doi: 10.3390/ijms12021222.
Rho kinase (ROCK) is a well-known downstream effector of Rho and plays an important role in various physiopathological processes. In this study, we aim to investigate the correlation between ROCK and microvascular damage in rat brain subjected to middle cerebral artery occlusion (MCAO) and reperfusion, and to elucidate the mechanisms underlying the microvascular damage. ROCK and matrix metalloproteinase 9 (MMP9) mRNA levels were determined by real time quantitative PCR, Laminin was detected by immunofluorescence and Blood Brain Barrier (BBB) permeability was examined by Evans Blue (EB) in rat MCAO models. We observed similar patterns of changes in ROCK expression, brain EB content, and Laminin expression at different time points after brain ischemia. Statistical analysis further confirmed a significant linear correlation of ROCK expression with the onset of microvascular damage in brain. Furthermore, the ROCK inhibitor fasudil decreased brain EB content but increased Laminin expression. These results provide strong evidence that ROCK mediates microvascular damage. In addition, we found that fasudil could significantly inhibit MMP9 expression induced by ischemia. Thus, our findings suggest that ROCK promotes microvascular damage by upregulating MMP9 and reveal ROCK as a promising therapeutic target for stroke.
Rho激酶（ROCK）是Rho众所周知的下游效应器，在各种生理病理过程中发挥重要作用。在本研究中，我们旨在探讨ROCK与大脑中动脉闭塞（MCAO）及再灌注大鼠脑微血管损伤之间的相关性，并阐明微血管损伤的潜在机制。通过实时定量PCR测定ROCK和基质金属蛋白酶9（MMP9）的mRNA水平，在大鼠MCAO模型中通过免疫荧光检测层粘连蛋白，并用伊文思蓝（EB）检测血脑屏障（BBB）通透性。我们观察到脑缺血后不同时间点ROCK表达、脑EB含量和层粘连蛋白表达的变化模式相似。统计分析进一步证实ROCK表达与脑微血管损伤的发生之间存在显著的线性相关性。此外，ROCK抑制剂法舒地尔降低了脑EB含量，但增加了层粘连蛋白表达。这些结果提供了强有力的证据表明ROCK介导微血管损伤。此外，我们发现法舒地尔可显著抑制缺血诱导的MMP9表达。因此，我们的研究结果表明ROCK通过上调MMP9促进微血管损伤，并揭示ROCK是中风的一个有前景的治疗靶点。
