【Animal modeling】-Changes and significance of protein expression of microRNA-97a and TGF-β1 in myocardial tissue of spontaneously hypertensive rats

  Objective: To observe the expression changes and relationship between Micro RNA-97a and TGF-β1 protein in myocardial tissue of spontaneously hypertensive rats (SHR).

  Methods: Eight 8-week-old male spontaneously hypertensive rats were selected as the SHR group, and 8 8-week-old male Wistar rats were selected as the control group. The rats were sacrificed by bloodletting, HE staining was used to observe the morphological changes of the rat heart, the expression of miRNA-97a in the rat heart was detected by PCR, and TGF-β1, angiotensin II (AngⅡ) protein and collagen type I (Col- I) and collagen type III (Col-III) protein expression levels.

  Results: The systolic blood pressure and diastolic blood pressure in the SHR group were significantly increased, the myocardial CVF and PVCA were significantly increased, the expression levels of TGF-β1 protein, Col-I and Col-III proteins were significantly increased, and the expression level of miRNA-97a was significantly decreased. Compared with the control group, the difference was statistically significant (P<0.01). The PCR results showed that the expression level of myocardial miRNA-97a in the SHR group was (24.6±4.7)% of that in the control group, and there was a negative correlation between the expression level of miRNA-97a and TGF-β1 protein in the myocardial tissue of the SHR group (r=-0.785, P<0.01). .

  Conclusion: The expression of miRNA-97a in SHR myocardial tissue is down-regulated, accompanied by the increase of TGF-β1 protein expression and collagen synthesis. miRNA-97a and TGF-β1 may be involved in myocardial fibrosis in SHR rats.