- Potential long-term cardioprotection was investigated in an extensive experimental study. Lactobacillus cultivation components (LCC) were administered intravenously in anesthetized rats 1, 7, and 21 days before global ischemia (GI). GI was produced by full stop flow in isolated Langendorff-perfused hearts for 20 min and was followed by reperfusion. Control animals were injected with saline. LCC reduced reperfusion tachyarrhythmia significantly and improved functional recovery of the ischemized rat heart. These beneficial effects were associated with reduction of release of norepinephrine (NE) and prostacyclin at the first minute of reperfusion, activation of myocardial catalase, and overexpression of 70-kDa heat stress protein (HSP-70) at ischemia and reperfusion (P < 0.05). This cardioprotection was documented up to 21 days after a single injection of LCC. Thus Lactobacillus cultivation components are new nontoxic materials that produce marked long-term cardioprotection against ischemia-reperfusion damage. This effect is attributed to an activation of the cellular defense system, manifested by activation of the antioxidant pathway and by expression of protective proteins. NE is involved in this process, and the data also suggest a role for prostacyclin in this model of cardioprotection. The potential of LCC and related compounds working through similar mechanisms in the prevention and therapy of various ischemic heart syndromes should be explored.