PMC

Effect of paraoxonase genotype on paraoxonase activity and myocardial blood flow parameters. Effect of paraoxonase genotype on (a) paraoxonase activity, (b) response to cold pressor testing (ΔMBF, increase in myocardial blood flow), (c) rest MBF, (d) stress MBF, and (e) MFR. Note that the paraoxonase genotype only had an effect on paraoxonase plasma levels (p < 0.0001), while there was no association with PET-measured indices of endothelium-dependent (ΔMBF) or -independent (stress MBF, MFR) vasomotion. Asterisks represent p < 0.0001 vs. wild type [WT] + heterozygotes and p < 0.0001 vs. homozygote-MM; dagger represents p = 0.083 vs. homozygotes-MM.

Effect of repeated exercise on (a) paraoxonase to high-density cholesterol concentration ratio (PON/HDL-C) and (b) paraoxonase to paraoxonase 1 concentration ratio (PON/PON1c) (mean ± SD). ^∗Before vs. bout of exercise, p < 0.05.

Paraoxonase activity in ocular tissues. (A) Arylesterase (AREase) activity of paraoxonase in ocular tissues: amongst the ocular tissue lysates, the lens had the highest activity, followed by retina, choroid, ciliary, iris and vitreous. (B) Thiolactonase (HCTLase) activity of paraoxonase in ocular tissues: the lens had the highest activity followed by retina, choroid, ciliary, iris and vitreous similar to the arylesterase activity.

Activity of HDL-associated paraoxonase was measured using phenylacetate as substrate. Paraoxonase activity of apoB-depleted sera was calculated from the slopes of the kinetic chart. Values shown represent means of four independent experiments.