Preservation of oligodendroglial cytoplasm in cryopreservative-pretreated frozen white matter.

Various cryoprotective agents [glycerol, dimethylsulphoxide, polyvinylpyrrolidone (PVP 40)], all dissolved in Krebs phosphate medium were tested for their effects on cytoplasmic preservation in oligodendroglia isolated from bovine white matter sorted at -30 degrees C. Of these agents, only PVP 40 (15% wt/vol) produced a significant improvement in recovery of oligodendroglial cytoplasm compared with untreated frozen brain. Cels isolated after PVP 40 pretreatment contained levels of membrane-bound enzymes similar to those found in cells isolated from fresh white matter. There was however, some loss of soluble protein. Studies of galactocerebroside synthesis in neuronal and oligodendroglial perikarya have shown that the glial cells contain ceramide galactosyltransferase at much higher specific activity than the neurones.