OJECTIVETo observe the effect of tianma gouteng decoction (TGD) on the endothelial function and the renal protein expression of spontaneously hypertensive rats, and to analyze its possible mechanism.

METHODSTotally 18 6-week-old SHR were randomly divided into 3 groups according to randomized block design, the SHR control group, the TGD group, and the captopril group, 6 in each group. Meanwhile, Wistar Kyoto (WKY) rats of the same age were recruited as a WKY control group. Rats in the TGD group were administered with TGD at the daily dose of 10. 260 g/kg. Rats in the captopril group were administered with captopril at the daily dose of 3. 375 g/kg. 2 mL/100 g distilled water was administered to rats in the SHR control group and the WKY control group. All medication was performed by gastrogavage once per day till rats were 24 weeks old. Changes of blood pressure were measured once per two weeks. The relaxation of the thoracic aorta and the superior mesenteric artery was determined by vascular ring in vitro to reflect the endothelial function. The total renal protein was separated by two-dimensional electrophoresis (2-DE). The significantly deviated protein was verified by Western blot.

RESULTS(1) Compared with the SHR control group, blood pressure was significantly lowered in rats (10 - 24 weeks old) of the captopril group (P <0.01, P <0.05). The hypotensive effect of TGD was obvious at the beginning of hypertension (10 -12 weeks) (P <0. 01). But along with the progression of hypertension, its hypotensive effect was not obvious (P>0. 05). (2) Compared with the SHR control group, the relaxation of the superior mesenteric artery was obviously improved in the TGD group (P <0. 05); the relaxation of the thoracic aorta and the superior mesenteric artery was obviously superior in the WKY control group (P <0. 01, P <0. 05). But there was no statistical difference in each relaxation index between the captopril group and the SHR control group (P >0. 05).(3) RESULTS: of 2-DE found 16 significantly differential renal protein, mainly involved nitric oxide (NO) system, oxidative stress, and cytoskeleton-related proteins. Results of Western blot showed that TGD could significantly improve expressions of Cu-Zn superoxide dismutase (SOD), N(G, N(G)-dimethylarginine dimethylaminohydrolase 2 (DDAH2), and pterin-4-alpha-carbinolamine dehydratase 1 (PCBD1) (P <0. 05).

CONCLUSIONGTD could protect the endothelial function of the superior mesenteric artery in SHR, and its intervention mechanism of hypertension induced early renal injury might be relevant to regulating the NO system and antioxidative stress.