Acute neuronal apoptosis in a rat model of multiple sclerosis

Demyelination caused by inflammation of the CNS has been considered to be a major hallmark of multiple sclerosis (MS). Using experimental autoimmune e ncephalomyelitis, a model of MS, we demonstrate that an immune-mediated att ack of the optic nerve is accompanied by an early degeneration of retinal g anglion cells (RGCs). The decrease of neuronal cell density was correlated with functional disabilities as assessed by visual evoked cortical potentia ls and electroretinogram. Visual acuity was significantly reduced. DNA degr adation and activation of caspase-3 in RGCs indicate that cell death of RGC s is apoptotic. These findings show for the first time that an inflammatory attack against myelin components can lead to acute neuronal cell loss by a poptosis.