Experimental allergic encephalomyelitis. I. Oligodendroglial cell population in monkey brain at the acute stage.

Populations of oligodendroglial cells (ODC) visualized by the neuroglial impregnation technique were investigated in demyelinated (A), actively demyelinating (B) and non-demyelinating (C) zones in both the cerebral and cerebellar white matter of monkeys with active EAE lesions. A marked reduction of the ODC population (P less than 0.001) was recognized not only in zones A and B but also in zone C as compared with those of non-sensitized monkeys. This suggests that the injury seen in ODC precedes myelin sheath destruction.