The Effect of Sympathetic Denervation on Cerebral Arteriogenesis After Chronic Cerebral Hypoperfusion.

OBJECTIVE

To explore the effect of perivascular sympathetic nerve on cerebral collateral arteriogenesis in chronic cerebral hypoperfusion models of rats.

MATERIALS AND

METHODS

Chronic cerebral hypoperfusion model was established by right common carotid artery ligation for 8 weeks, while sympathetic denervation was performed by superior cervical ganglionectomy. The male Sprague-Dawley rats were randomly divided into 4 groups including sham group (n = 21), denervation group (n = 21), artery ligation group (n = 21) and combined group with both artery ligation and denervation (n = 21). After 8 weeks of surgery, the rats in each group were randomly divided into 3 subgroups including subgroup A (n = 7), subgroup B (n = 7) and subgroup C (n = 7). The 3 subgroups were subjected to latex perfusion, permanent right middle cerebral artery occlusion and immunohistochemical staining, respectively.

RESULTS

The diameters of right leptomeningeal anastomoses in artery ligation group significantly enlarged compared with sham group. When sympathetic denervation was performed in the presence of artery ligation, diameter of collateral vessel decreased, although larger than in sham group. After 8 weeks of permanent right middle cerebral artery occlusion, the cerebral perfusion over the right middle cerebral artery area in combined group was significantly lower than in artery ligation group, although both were higher than in denervation group and sham group. Triphenyltetrazolium chloride staining showed that cerebral infarct volume in combined group was significantly larger than in artery ligation group, and smaller than in denervation group and sham group. Neurologic functional scoring showed that scores in combined group were significantly higher than in artery ligation group, and lower than in denervation group and sham group. Immunohistochemical staining for α-smooth muscle actin showed that compared with sham group, tunica media thickness of right leptomeningeal anastomoses in artery ligation group increased significantly. Thickness in combined group was thinner than in artery ligation group, although thicker than in sham group.

CONCLUSIONS

Perivascular sympathetic denervation can impair the cerebral collateral arteriogenesis under condition of chronic cerebral hypoperfusion.