Efeito protetor de nova solução cardioplégica com histidinatriptofano- glutamato em coração isolado de ratos

Abstract

Introduction: Solutions that cause elective cardiac arrest are often evolving, but the ideal compound has not yet been found. The authors compare a new cardioplegic solution with histidine-tryptophan-glutamate (HTG) with histidine-tryptophan-acetoglutarato (HTK) in a model of isolated rat heart. Objective: Benchmarking HTK and HTG solutions regarding the activity of caspase, KI -67, IL - 8, Shannon entropy and fractal dimension. Materials and Methods: Twenty male rats, Wistar race, were analyzed and heparinized. The chest was opened, held and cardiectomia infused 40 mL/kg of appropriate cardioplegia. The hearts were kept for 2 hours at 4°C in the same solution, and afterwards placed in the Langendorff apparatus for 30 min with Ringer-Locke solution. The immunohistochemical analyses were performed for caspase, IL-8, KI-67, Shannon entropy and fractal dimension. Results: The concentration of caspase was lower in group 2, and KI-67 was higher in group 2, both P<0.05. There was no statistical difference between the values of IL-8 between the groups. Both the Shannon entropy and the fractal dimension were not different in the two groups. Conclusions: The HTG solution was better than with HTK because they had reduced caspase (apoptosis) increased KI-67 (cell proliferation), they did not show different values of IL-8 (inflammation, necrosis). Additionally they did not show change in amount or distribution of the information (observed by the Shannon entropy and fractal dimension) in histological slices.