Calmodulin and malignant hyperpyrexia.

The function of calmodulin as a biological regulator is linked to the level of free Ca2+ in the cell, and there is evidence that calmodulin may itself be involved in the control of the movements of cellular Ca2+. Malignant hyperpyrexia, on the other hand, is caused by a disturbance in the level of myoplasmic Ca2+. We have investigated the possibility that calmodulin may be involved in malignant hyperpyrexia by studying the trifluoperazine-induced inhibition of calmodulin activation by phosphodiesterase, using crude and purified calmodulin preparations from control and MH-susceptible pigs.

Electrophoretic analysis of proteins in malignant hyperpyrexia susceptible skeletal muscle.

Malignant hyperpyrexia (MH) is an anaesthetic complication which is due to an underlying muscle membrane abnormality. One- and two-dimensional electrophoresis of skeletal muscle proteins were carried out to study the abnormality. No defect in MH susceptible muscle was found.

Comparison of adenylate kinase from normal and malignant hyperpyrexic porcine muscle.

Adenylate kinase has been implicated as a key factor in malignant hyperpyrexia, a complication of general anaesthesia which is usually triggered by the anaesthetic drug, halothane. Because of this, the enzyme was purified from both malignant hyperpyrexia susceptible and control porcine muscle. Electrophoretic studies, amino acid analysis, and peptide mapping of the purified enzymes revealed no significant differences between the two preparations.

Effect of halothane on adenylate kinase in porcine malignant hyperpyrexia.

The effects of halothane on adenylate kinase activity in porcine muscle have been examined. No abnormality in malignant hyperpyrexia susceptible muscle was found. At clinical concentrations of halothane only slight inhibition of adenylate kinase activity was observed.