Remote and local ischemic preconditioning equivalently protects rat skeletal muscle mitochondrial function during experimental aortic cross-clamping

Objective: This study investigated whether remote (rIPC) and local ischemic preconditioning (IPC) similarly limit skeletal muscle dysfunction induced by aortic cross-clamping. Methods: Rats were divided in three groups: the sham-operated control group (C) underwent surgery without clamping. The ischemia-reperfusion group (IR) had 3 hours of ischemia induced by aortic clamping and collateral vessels ligation, followed by 2 hours of reperfusion. The IPC group had, before prolonged ischemia, three bouts of 10 minutes of ischemia and 10 minutes of reperfusion on the right hind limb. Thus, right hind limbs had local IPC and left hind limbs had rIPC. Complexes I, II, III, and IV activities of the mitochondrial respiratory chain of the gastrocnemius muscle were measured using glutamate-malate (V-max), succinate (V-succ), and N,N,N',N'-tetramethyl-p-phenylenediamine dihydrochloride (TMPD)-ascorbate V((TMPD)). Expressions of genes involved in apoptosis (Bax, Bcl-2) and antioxidant defense (superoxide dismutase I [SOD 1], SOD2, glutathione peroxidase [GPx]) were determined by quantitative real-time polymerase chain reaction. Glutathione was also measured. Results: Right and left hind limb mitochondrial functions were similar in controls and after IR. IR reduced V-max (-21.2%, 6.6 +/- 1 vs 5.2 +/- 1 mu mol O-2/min/g dry weight, P = .001), V-succ (-22.2% P = .032), and V-TMPD (-22.4%, P = .033), and increased Bax (63.4%, P = .020) and Bax/Bcl-2 ratio (+84.6%, P = .029). SODs and GPx messenger RNA were not modified, but glutathione tended to be decreased after IR. Local IPC and rIPC counteracted similarly these deleterious effects, restoring mitochondrial maximal oxidative capacities and normalizing Bax, the Bax/Bcl-2 ratio, and glutathione. Conclusions: Remote ischemic preconditioning protection against IR injury is equivalent to that achieved by local IPC. It might deserve a broader use in clinical practice. (J Vase Surg 2012;55:497-505.)