Pharmacological protection of hypoxic heart.

The ability of beta-adrenoceptor antagonists, with and without intrinsic sympathomimetic activity, and of verapamil to protect the heart against hypoxia-induced damage was investigated. Damage was quantitated in terms of a raised end-diastolic resting tension and creatine phosphokinase (CPK) release. The results indicate that both the d and the l isomers act differently, the isomers preventing CPK release and the d isomers preventing the increase in resting tension.