Effects of metallothionein on isolated rat heart

Abstract

To investigate the effects of metallothionein (MT) on isolated rat heart, 16 Wistar rats were randomly divided into 2 groups. In control group (group C), distilled water was injected intraperitoneally and 24 h later isolated hearts were perfused with Langendorff and stored at 4°C for 3 h with histidine-tryptophan-ketoglutarate (HTK) solutions, and then isolated hearts were perfused for 2 h by Langendorff. In experimental group (group E), 3.6% ZnSO₄ was injected intraperitoneally, 24 h later isolated hearts were perfused by Langendorff and stored at 4°C for 3 h with HTK solutions, and then the isolated hearts were perfused for 2 h with Langendorff. MT content, the recovery of hemodynamics, myocardial water content (MWC), lactate dehydrogenase (LDH) and creatine kinase (CK) leakage, adenosine triphosphate (ATP) and malondialdehyde (MDA) content, superoxide dismutase (SOD) activity, myocardial cell Ca²⁺ content, Ca²⁺-ATPase activity of mitochondria ([Ca²⁺-ATPase]_m) and its Ca²⁺ content ([Ca²⁺]_m), synthesizing ATP activity of mitochondria ([ATP]_m), and the ultrastructure of cells were examined. There were a significant increase in group E in hemodynamic recovery, ATP content, SOD activity, [Ca²⁺-ATPase]_m activity, [ATP]_m activity, and substantial reduction in MWC, LDH and CK leakage, MDA content, myocardial cell Ca²⁺ content, [Ca²⁺]_m content, and the ultrastructural injury were obviously milder than that of group C. This study demonstrated that MT has protective effects on isolated rat heart.

Keywords

metallothionein / heart transplatation / cardioprotection

References

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