Endotoxin, Monophosphoryl Lipid A and Delayed Cardioprotection
In 1989, Brown and colleagues  demonstrated that pretreatment of rats with a low dose of endotoxin (lipopolysaccharide, LPS) 24 hours prior to heart isolation and perfusion in the Langendorff mode resulted in an enhanced post-ischaemic recovery of myocardial function (left ventricular developed pressure, + dP/dt) and an increase in catalase activity. Hearts isolated from rats which were pretreated with LPS for only 1 hour did not have an increased catalase activity or functional protection from ischaemia-reperfusion injury. These results suggested that the delayed cardioprotection produced by LPS was the result of enhanced antioxidant enzyme activity, particularly catalase.
KeywordsInfarct Size KATP Channel Ischemic Precondition Cardioprotective Effect Rabbit Heart
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