Effects of hydrogen sulphide on the isolated perfused rat heart

Abstract EN

Objectives : Hydrogen supplied has been identified as a gas signaling molecule in the body, and has previously been shown to have vasorelaxant properties.

The aim of the study was to investigate the effects of sodium hydrosulphide (NaHS), a hydrogen supplied donor, on heart rate (HR), left ventricular developed pressure (LVDP) and coronary flow (CF) in the isolated perfused rat heart.

Methods : A Langendorff isolated heart preparation was used to investigate the effect of a dose range of sodium hydrosulphide, in the presence and absence of inhibitors, on heart rate, left ventricular developed pressure and coronary flow.

Results : Sodium hydrosulphide caused a significant decrease in heart rate at a concentration of 10-3 M (P < 0.001).

This decrease was partially inhibited by glibenclamide, a KATP channel blocker (P <0.05); L-NAME, a nitric oxide synthase inhibitor (P <0.001), and ethylene blue (P <0.001), but not by H-89, a protein kinas A inhibitor.

Sodium hydrosulphide significantly increased coronary flow at concentrations of 10-4 – 10-3M (P <0.05).

This response was significantly increased in the presence of L-NAME (P <0.001) and ethylene blue (P <0.001), whereas H-89 inhibited the increase in coronary flow due to sodium hydrosulphide (P <0.001).

Sodium hydrosulphide significantly decreased LVDP at all concentrations (P <0.001).

In the presence of glibenclamide and H-89, the time period of the decrease in LVDP due to sodium hydrosulphide was extended (P <0.001), whereas ethylene blue and L-NAME caused a significant reduction in the response to sodium hydrosulphide (P < 0.05, P <0.01 respectively).

Conclusion: Sodium hydrosulphide reduced heart rate and LVDP, and increased coronary flow in the isolated perfused rat heart; however, the mechanisms of action could not be fully elucidated.