Hypercholesterolemia abrogates late preconditioning via a tetrahydrobiopterin-dependent mechanism in conscious rabbits.

ABSTRACT:

Background

Although the late phase of ischemic preconditioning (PC) is known to confer cardioprotection in healthy animal models, it is unknown whether this phenomenon exists in the presence of hypercholesterolemia. The goal of this study was to determine whether the infarct-sparing effect of late PC is affected by hypercholesterolemia and, if so, whether a tetrahydrobiopterin (BH4)-dependent mechanism is responsible for the loss of late PC.

Methods and results

Conscious rabbits fed a normal diet or a 1% cholesterol diet for 6 weeks were subjected to ischemic PC (six 4-minute coronary occlusion/4-minute reperfusion cycles) and, 24 hours later, underwent a 30-minute occlusion followed by 3 days of reperfusion. A total of 125 rabbits were used. In normocholesterolemic rabbits,

SUBMITTER: Tang XL 

PROVIDER: S-EPMC3671759 | biostudies-literature | 2005 Oct

REPOSITORIES: biostudies-literature