Anticonvulsive treatment of myelin-deficient (mld) mice improves survival and confirms the delayed increase of myelin basic protein.

Myelin-deficient (mld) mutant mice were treated with phenobarbital between 60 and 90 d of age. The survival rate at 90 d increased from 1.4% in untreated mutants to 46% in those who received phenobarbital. This is evidence that apneic spells during tonic seizures are a major cause of death in mld mice. Myelin basic protein (MBP) content of brain homogenates from treated mld mice increased significantly between 30 and 90 d. MBP was present in myelin purified from the 90-d-old treated mld mice. These results demonstrate that the MBP increase, which occurs after the active phase of myelin formation is completed, is a general phenomenon and is not caused by the selection of a small and mildly affected subpopulation of mutants.