Effects of apocynin treatment of rats in the absence and in the presence of HgCl2 on maximum response (Rmax) and sensitivity (pD2) to acetylcholine and sodium nitroprusside.

Parameters of maximal response (Rmax) and sensitivity (pD2) of the concentration-response curves to acetylcholine (ACh) and sodium nitroprusside (SNP) in aortas from rats untreated, treated with mercury (HgCl2), apocynin and apocynin plus mercury (ApoHg) in intact segments (Control). Results are expressed as mean±SEM. Rmax, maximal effect (expressed as a percentage of the previous contraction to phenylephrine) and pD2 expressed as -log one-half Rmax; t-test: *P#Pvs. HgCl2-treated.