[Tanshinone IIA sulfonate upregulated pulmonary artery smooth muscle peroxisome proliferator-activated receptor γ expression in monocrotaline induced pulmonary hypertension rat].

OBJECTIVE: To investigate the effect of sodium tanshinone IIA sulfonate (STS) on rat right ventricular systolic pressure (RVSP), mean right ventricular pressure (MRVP), right ventricular hypertrophy index [RV/(LV+S)], pulmonary vascular remodeling, and PPARγ protein expression in pulmonary artery smooth muscle of monocrotaline (MCT) induced rat pulmonary hypertension model.

METHODS: The pulmonary hypertension model was established by subcutaneously injection of MCT, and the rats were treated with or without STS for 21 days. After that, RVSP, mRVP and RV/(LV+S) were measured. Lung histopathological sections were prepared, and the lumen area, the wall thickness and arterial radius of pulmonary arteries were quantified using the Image Pro Plus 6.0 software. PPARγ protein expression in rat pulmonary artery smooth muscle was detected by Western blot.

RESULTS: Compared with control group, the RVSP, mRVP were significantly increased in MCT group (P < 0.05), while in the MCT+STS group, it was decreased from (81.2 ± 1.9) and (28.6 ± 2.0) mmHg to (35.4 ± 8.3) and (14.1 ± 5.4) mmHg, respectively (P < 0.05). The RV/(LV+S) of MCT group was (0.57 ± 0.04), markedly higher than those of control group and control+STS group (0.33 ± 0.02) and (0.34 ± 0.02) , respectively, P < 0.05, while in MCT+STS group, the RV/(LV+S) was (0.43 ± 0.02), lower than that of MCT group (P < 0.05) ;The luminal area/total area of MCT group decreased to (27 ± 6)%compared with control rats (56.00 ± 3.00) % (P < 0.05) . The wall thickness/artery radius (WT%) of MCT group increased from (20 ± 4) % (control group) to (40 ± 3) % (P < 0.05) .In MCT+STS treated rats, luminal area/ total area and WT% were (39.0 ± 2.0) %and (31.0 ± 2.0) %, both statistically different from MCT group (P < 0.05) . The level of PPARγ protein in pulmonary artery smooth muscle of MCT group was (48 ± 4) %, lower than control group (100 ± 0) % (P < 0.05) .In the MCT+STS group, PPARγ protein expression was recovered (102 ± 3) %, (P < 0.05) .

CONCLUSION: STS markedly decreased RVSP,MRVP, RV/(LV+S) and pulmonary vascular remodeling in MCT induced pulmonary hypertension rat, and PPARγ might be targeted as a key molecule during STS treatment.