Protective effect of methylprednisolone sodium succinate on the ultrastructure and resting tension of hypoxic heart muscle.

Experiments were undertaken to further investigate the protective effect of methylprednisolone sodium succinate on hypoxic heart muscle. Hypoxia was induced in isolated Langendorff perfused rat and rabbit hearts by gassing the perfusate with 95% N2 + 5% CO2. The hypoxia-induced damage was quantitated in terms of an altered ultrastructure and increased resting tension. When added at the start of the hypoxic episode 6 X 10(-5) mol.litre-1 methylprednisolone sodium succinate protected the fine ultrastructure of the heart, and delayed the increase in resting tension. This protective effect could not be accounted for in terms of the sodium succinate moiety.