The role of hydrogen sulfide system in the pathogenesis of renovascular hypertension in rats

Objective To investigate the role of hydrogen sulfide (H2S) synthases / H2S pathway in the pathogenesis of renovascular hypertension. Methods Wistar rats were subdivided into 4 groups: (1) 2-kidney, 1-clip (2K-1C group, n=7), (2) control (n=7), (3) sham (n=7), and (4) 2K-1C plus sodium hydrosulfide (NaHS) (NaHS-treated group, n=7). The systolic blood pressure (SBP) was measured by a tail-cuff method using a pulse transducer once a week. Four weeks later, all rats were killed and the concentration of plasma hydrogen sulfide (H2S), the activity of the H2S synthases in the kidneys on both sides, the plasma angiotensin￠òconcentration, and the left-to-whole heart weight ratio were measured. Results The SBP was significantly increased in the 2K-1C group(185.4±14.0mmHg) comparing with those in the sham group ( 112.9±6.5mmHg, , or the NaHS-treated group(134.8±9.5mmHg) (both P<0.01). At 4 weeks, the angiotensin ￠òconcentration in the plasma was increased in the 2K-1C and NaHS-treated group, comparing with the control and the sham group (306.92±7.03 pg/ml and 240.73±13.22 pg/ml vs 122.6±25.49 pg/ml and 125.95±10.55 pg/ml, respectively, both P<0.05). The plasma H2S concentration and the activity of H2S synthases in the left kidney were decreased in the 2K-1C group comparing with those in the sham and the control groups. There was no difference of the activity of the H2S synthases in the right kidneys among the 4 groups. The left-to-whole heart weight ratio was increased in the 2K-1C and the NaHS-treated group camparing with that in the sham and natural control groups. Conclusion Dysfunction of the H2S synthases/H2S pathway was involved in the 2K-1C-induced renovascular hypertension in rat. Exogenous administration of H2S donor can attenuate the development of hypertension. These findings suggest that the H2S synthases/H2S pathway participates in the pathogenesis of renovascular hypertension.