Abnormal membrane composition and membrane-dependent transduction mechanisms in cluster headache.

Previous studies have indicated that membrane structure and function may be abnormal in cluster headache. This has been further investigated by analysis of membrane phosphatidylcholine, total phospholipids, and cholesterol in erythrocytes and by assay of receptor-mediated transduction. The stimulation of lymphocyte adenylate cyclase with isoprenaline and prostacyclin was used as the test system. A significant increase in the ratio of membrane phosphatidylcholine to cholesterol without change in cholesterol was found in cluster headache patients as compared with control subjects. This indicated a reduced turnover of phosphatidylcholine, since erythrocyte choline is significantly reduced in this condition. Abnormal membrane function was also indicated from the significant depression of high-affinity prostaglandin receptor stimulation of lymphocyte adenylate cyclase and the similar trend in the beta-adrenoceptor response. Since no change in agonist affinity and beta-adrenoceptor density occurred, this depression indicates a generalized defect in coupling of receptors to adenylate cyclase. It is hypothesized that the impaired function that would result might contribute to the aetiology of cluster headache.