Ischemic preconditioning: lack of delayed protection against skeletal muscle ischemia-reperfusion.
We investigated the ability of ischemic preconditioning to induce expression of heat shock protein 70 (Hsp 70) and/or to increase muscle survival after ischemia-reperfusion in the rat hind limb. Ischemic preconditioning regimens tested were; 1 x 5 min of ischemia, 4 x 5 min of ischemia interrupted by 10 min of reperfusion, 1 x 10 min of ischemia or 2 x 10 min of ischemia interrupted by 15 min of reperfusion. Western blot analysis revealed only a modest induction of Hsp 70 at 24 h after preconditioning using the latter two protocols of 1 x 10 min of ischemia or 2 x 10 min. Used at 24 h prior to prolonged ischemia, neither protocol improved muscle survival measured at 24 h after reperfusion. In conclusion, ischemic preconditioning did not produce delayed protection from ischemia-reperfusion in this model and the study suggests that ischemic preconditioning is not a useful protective strategy against skeletal muscle necrosis in the long-term.
Lepore
D A
DA
Bernard O'Brien Institute of Microsurgery, St. Vincent's Hospital, Fitzroy, Melbourne, Australia. d.lepore@surgerysvh.unimelb.edu.au
Morrison
W A
WA
D000818:Animals; D018840:HSP70 Heat-Shock Proteins / Q000096:biosynthesis; D019194:Ischemic Preconditioning; D008297:Male; D018482:Muscle, Skeletal / Q000098:blood supply* / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D015427:Reperfusion Injury / Q000517:prevention & control*; D013997:Time Factors
D018840:HSP70 Heat-Shock Proteins