Expression of monocyte chemoattractant protein-1 in the cerebral artery after experimental subarachnoid hemorrhage

Monocyte chemoattractant protein-1 (MCP-1) is a potent chemokine that plays an important role in the recruitment of macrophages. Although previous studies have demonstrated that MCP-1 has been shown to be involved in the damaging inflammatory processes associated with stroke, infection, neoplasia, and others in the central nervous system, the role of MCP-1 in the cerebral artery after experimental subarachnoid hemorrhage (SAH) in rats has been largely unexplored. This study was undertaken to investigate the expression of the MCP-1 in SAH model and to clarify the potential role of MCP-1 in cerebral vasospasm. A total of 80 rats were randomly divided into four groups: control group; day 3, day 5, and day 7 groups. Day 3, day 5, and day 7 groups were all SAH groups. The animals in day 3, day 5 and day 7 groups were subjected to injection of autologous blood into cisterna magna twice on day 0 and day 2 and were killed on days 3, 5, and 7, respectively. Cross-sectional area of basilar artery was measured and the MCP-1 expression was assessed by real-time PCR, Western blot and immunohistochemistry. The cross-sectional area of basilar artery was found to be 85,373+/-8794 mum(2) in control group, 59,210+/-7281 mum(2) in day 3, 50,536+/-6519 mum(2) in day 5, and 66,360+/-7452 mum(2) in day 7, respectively. The basilar arteries exhibited vasospasm after SAH and became more severe on day 5. The elevated mRNA and protein of MCP-1 were detected after SAH and peaked on day 5. MCP-1 is increasingly expressed in a parallel time course to the development of cerebral vasospasm in a rat experimental model of SAH and these findings might have important implications during the administration of specific MCP-1 antagonists in order to prevent or reduce cerebral vasospasm caused by SAH.