Reduction of nitro-BT by various chloroform-methanol fractions obtained from the grey matter of the rat brain.

Histochemical studies have shown, that nerve fibers can not be visualised in the grey matter of the brain by the reduction of Nitro-BT, if prior to incubation an extraction with chloroform-methanol of the brain slices was performed. According with this finding the grey matter of the rat brain was homogenized and extracted with chloroform-methanol. After centrifugation the obtained supernatant was three times evaporated. Each time before evaporation the supernatant was dissolved in chloroform-methanol solution v/v 2:1. The substance obtained was of teer-like consistency and brown colour. The substance was weight and used for further experiments. Similar extraction was done with phosphate buffer. It was found, that the phosphate buffer does not extract the searched for substance. The comparison of the extinction curves of various fractions has shown that the highest concentration of the substance which reduces Nitro-BT can be found in that fraction which was three times washed with chloroform-methanol. The same concentration was observed in the water fraction which was the result of purification with hexanmethanol. From our investigations it may be concluded that the substance which reduces Nitro-BT in tissue is bound with lipids and purified form lipids passes into water.