Allitridum mimics effect of ischemic preconditioning by activation of protein kinase C

AIM: To investigate whether allitridum has the effect of pharmacological pr econditioning and whether protein kinase C (PKC) plays a role in myocardial protection. METHODS: Thirty-four isolated rabbit hearts which subjected to 30 min of regional myocardial ischemia and 2 h reperfusion, were randomly divided into 5 groups: control group, ischemic preconditioning (PC) group, allitridum (A) group, polymyxin B (Poly B) group, allitridum + polymyxin B (A + PolyB) group. Infarct size was determined by triphenyltetrazolium stai ning. RESULTS: Pharmacological preconditioning in hearts with a 5-min allit ridum infusion 10 min before the prolonged regional ischemia resulted in si gnificantly smaller infarcts (7% +/- 6% of risk area) than in control heart s (25% +/- 7%, P <0.05). There is no significant difference in infarct size between (A + Poly B) group and control hearts (23% +/- 5% vs 25% +/- 7%, P > 0.05). CONCLUSION: These data indicate that allitridium can precondition rabbit ischemic myocardium and this protection can be effectively blocked by administration of Poly B, an inhibitor of PKC, implying that PKC has an important role in preconditioning.