Ischemic and ozone oxidative preconditioning in the protection against hepatic ischemic-reperfusion injury

It has been demonstrated that ozone, probably by means of an oxidative preconditioning (OP) mechanism, protected the liver against the damage mediated by reactive oxygen species. Taking into account that ischemic preconditioning (IschP) is also a protective mechanism, a comparative study between both preconditioning effects, with the aim to study the effectiveness of both protective procedures, was performed. Rats were divided at random in: 1- control, sham operated (anesthesia and laparotomy plus surgical manipulation); 2- I/R (ischemia for 90 min followed by 90 min reperfusion); 3- IschP + I/R, as group 2 but submitted to a previous ischemic preconditioning (ischemia 10 min and reperfusion 10 min); 4- OzoneOP + I/R, as group 2 but submitted to a previous oxidative preconditioning with 15 sessions, daily, of ozone by rectal administration (dose = 1 mg/kg). The comparison between both preconditionings showed no biochemical differences for the parameters evaluated. Nevertheless, the histological study demonstrated that the protective effect produced by the OzoneOP is superior to that achieved with the IschP.