RESUMEN
OBJECTIVE@#To investigate the effect of bilateral superior cervical sympathetic ganglion occlusion (SCG) on aortic dissection and its possible mechanism.@*METHODS@#Forty-five SD rats were randomly divided into three groups with 15 in each:blank control group, sham operation group and SCG group. β-aminopropione (666 mg·kg·d) was given by subcutaneous injection for 4 weeks to establish the aortic dissection model. Rats in SCG group were given SCG before the injection of β-aminopropione. Blood pressure and heart rate of the rats were monitored using noninvasive tail artery blood pressure measuring instrument; sympathetic activity was monitored using drug block method; the structure of aortic wall was observed using HE staining; collagen fibers in aortic wall was observed using Sirius red staining; protein expression of Apelin was detected by immunohistochemistry; and the protein expression of matrix metalloproteinase (MMP)-2, 9 was detected by Western blotting.@*RESULTS@#During the experiment, the body mass of the sham operation group and SCG group was smaller than that of the blank control group (all <0.05), and the body mass of the SCG group was larger than that of the sham operation group (all <0.05). The heart rate and sympathetic activity of the sham operation group were higher than those of the blank control group (all <0.05), while the SCG group were lower (all <0.05). Compared with the blank control group, the aortic wall in the sham operation group was thickening, while that in the SCG group was improved. A large number of collagen-1 in the aortic wall of the blank control group was stained brown by Sirius red, which was lighter in SCG group, and the staining in the sham operation group was the lightest. Compared with the blank control group, the expression of Apelin, MMP-2 and MMP-9 protein in the sham operation group increased (all <0.05), while those in the SCG group decreased (all <0.05).@*CONCLUSIONS@#SCG can effectively reduce the incidence and mortality of aortic dissection in rats, which may be related to the inhibition of sympathetic activity and the decrease of collagen-1, Apelin, MMP-2 and MMP-9 expression.