CARNITINE PALMITOYL TRANSFERASE DEFICIENCY IN MALIGNANT HYPERTHERMIA

The activity of carnitine palmitoyl transferase, an enzyme that cataly zes the transport of long-chain acylcarnitines into mitochondria, was quantitated in EB-virus-transformed lymphoblasts from 7 patients with susceptibility for malignant hyperthermia. Immunoreactive enzyme prote in was also measured using an enzyme-linked immunosorbent assay. Cell lines derived from patients with carnitine palmitoyl transferase defic iency of muscle and from normal individuals were used as positive and negative controls, respectively. One patient with malignant hypertherm ia had a deficiency in the enzyme activity which was comparable with t hat of the known carnitine palmitoyl transferase deficient patients. T his individual's lymphoblasts were also deficient in immunoreactive en zyme protein. All of the remaining patients with malignant hyperthermi a were deficient only when the backward assay for carnitine palmitoyl transferase was used for quantitation. It is likely that a subset of i ndividuals with a malignant hyperthermia phenotype have a primary defi ciency of carnitine palmitoyl transferase and that others have a milde r enzyme deficiency secondary to the primary defect in malignant hyper thermia.