Related Experiment Video
Updated: Jul 5, 2026

Isolation of Pulmonary Artery Smooth Muscle Cells from Neonatal Mice
Published on: October 19, 2013
Exogenous hydrogen sulfide inhibits superoxide formation, NOX-1 expression and Rac1 activity in human vascular smooth
Saima Muzaffar1, Nilima Shukla, Mark Bond
1Bristol Heart Institute, University of Bristol, Bristol, UK. S.Muzaffar@bris.ac.uk
Abstract:
The activity of NADPH oxidase (NOX) is blocked by nitric oxide (NO). Hydrogen sulfide (H(2)S) is also produced by blood vessels. It is reasonable to suggest that H(2)S may have similar actions to NO on NOX. In order to test this hypothesis, the effect of sodium hydrosulfide (NaHS) on O(2)(-) formation, the expression of NOX-1 (a catalytic subunit of NOX) and Rac(1) activity (essential for full NOX activity) in isolated vascular smooth muscle cells (hVSMCs) was investigated. hVSMCs were incubated with the thromboxane A(2) analogue U46619 +/- NaHS for 1 or 16 h, and O(2)(-) formation, NOX-1 expression and Rac(1) activity were assessed. The possible interaction between H(2)S and NO was also studied by using an NO synthase inhibitor, L-NAME, and an NO donor, DETA-NONOate. The role of K(ATP) channels was studied by using glibenclamide. NaHS inhibited O(2)(-) formation following incubation of 1 h (IC(50), 30 nM) and 16 h (IC(50), 20 nM), blocked NOX-1 expression and inhibited Rac(1) activity. These inhibitory effects of NaHS were mediated by the cAMP-protein-kinase-A axis. Exogenous H(2)S prevents NOX-driven intravascular oxidative stress through an a priori inhibition of Rac(1) and downregulation of NOX-1 protein expression, an effect mediated by activation of the adenylylcyclase-cAMP-protein-kinase-G system by H(2)S.
Related Concept Videos
Nitric Oxide Signaling Pathway
Antihypertensive Drugs: Vasodilators
The Electron Transport Chain
Inhibitors of the electron transport chain
Rotenone, a widely used pesticide, prevents electron transfer from Fe-S cluster to ubiquinone or Q in...
Electron Transport Chain: Complex III and IV
Preparation and Reactions of Sulfides
Peroxisomes

