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 Ⅱconcentration, 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 Ⅱ concentration 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. Conclusions 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.