【Animal Modeling】-What is the role of RhoA/ROCK signaling pathway in the rat model of pulmonary hypertension caused by left heart disease?

  Objective: To investigate the expression level and role of RhoA/ROCK signaling pathway in a rat model of left heart disease-related pulmonary hypertension.

  Method: 20 male SD rats aged 3-4 weeks and weighing 90-100 g were randomly divided into a control group (group C: n = 10) and a pulmonary hypertension group (group H: n = 10). In group H, we fixed and contracted the ascending aorta to construct a rat model of pulmonary hypertension associated with left heart disease. Rats in group C received sham operation (titanium clamps were fixed in the paravascular mediastinum tissue instead of the ascending aorta). , And all other operations are the same as group H), 60 days after modeling, test the hemodynamics (right ventricular systolic pressure, pulmonary artery pressure) of each group of rats, and test in vivo at the expense of rats with PBS Perform cardiopulmonary lavage. Both lungs turned white, the left lung tissue was fixed with 4% paraformaldehyde to observe the pathological changes of the lung tissue, and the right lung tissue was frozen for biomolecular detection (Rho. Kinase mRNA, RhoA mRNA, ET-A receptor mRNA ).

  Result: Compared with group C, the pulmonary artery pressure and right ventricular systolic pressure in group H were significantly increased (P\u003c0.01), the pulmonary artery wall was significantly thickened, the pulmonary artery became narrow or narrowed, and even obstruction occurred. The wall enlargement index increased significantly. Large (P\u003c0.01); Compared with group C, the expression level of Rho kinase mRNA in the lung tissue of group H was significantly increased, and the expression levels of RhoA mRNA and ET-A receptor mRNA also increased. Significance and difference are statistically significant (P\u003c0.01).

  Conclusion: A rat model of left heart disease-related pulmonary hypertension was successfully established through the fixation and contraction of the ascending aorta. Compared with group C, small lung vessel walls in group H were significantly thickened, and the expression of Rho kinase mRNA, RhoA mRNA and RhoA mRNA and ET-A receptor mRNA in lung tissue were significantly increased, which may be related to signal transduction pathways. In the formation of pulmonary hypertension associated with left heart disease.