NMR relaxation of water protons in normal and malignant hyperthermia-susceptible pig muscle.

(1)H-NMR has been used to study the evolution of water proton transversal relaxation times in ageing skeletal muscles of normal and halothane-positive Pietrain pigs. Malignant hyperthermia was confirmed by the caffeine contracture test. Lactic acid, creatine phosphate, and ATP levels in muscle biopsies were measured by biochemical analysis. The NMR dynamic results revealed malignant hyperthermia, but knowledge of animal age and muscle type improved significantly the detection ability. The NMR results revealed large differences between muscles. Halothane sensitivity detection seems to be less affected by animal age, than by muscle effect but discrimination was more efficient in the older animal group. It is concluded that (1) H-NMR is a suitable method for diagnosing halothane sensitivity on a well identified muscle biopsy and that water dynamics might be related to acidosis in muscle fibres.