Hydrogen sulfide improves the endothelial dysfunction in renovascular hypertensive rats

Area of Science:

• Cardiovascular Physiology
• Endocrinology
• Pharmacology

Background:

• Hydrogen sulfide (H2S) is a novel gasotransmitter with known vasodilating and antihypertensive effects.
• Renovascular hypertension, such as in the two-kidney one-clip (2K1C) rat model, often involves endothelial dysfunction.
• The role of H2S in ameliorating endothelial dysfunction in renovascular hypertension requires further investigation.

Purpose of the Study:

• To investigate the potential beneficial effects of H2S on thoracic endothelial function in 2K1C rats.
• To determine if H2S administration can mitigate hypertension and associated vascular oxidative stress in this model.

Main Methods:

• Two-kidney one-clip (2K1C) surgery was performed on rats to induce renovascular hypertension.
• Sodium hydrosulfide (NaHS) was administered intraperitoneally to 2K1C rats.
• Systolic blood pressure (SBP), oxidative stress markers (MDA, SOD), and oxidative stress-related protein expression were measured.
• Acetylcholine-induced vasorelaxation and Angiotensin II-induced vasocontraction were assessed in isolated thoracic aortas.

Main Results:

• NaHS administration significantly lowered the elevated SBP in 2K1C rats.
• H2S supplementation ameliorated endothelial dysfunction, improving vasorelaxation responses.
• Vascular oxidative stress was reduced, evidenced by downregulated oxidative stress-related proteins and upregulated SOD activity.
• The protective effects involved inhibition of Angiotensin II-AT1R signaling and reduced oxidase activity.

Conclusions:

• H2S exerts antihypertensive effects in 2K1C rats, partly through improving endothelial function.
• The protective mechanism of H2S involves the suppression of vascular oxidative stress.
• H2S may be a potential therapeutic agent for managing renovascular hypertension by targeting oxidative stress pathways.