[DNAse-I inhibition by the chromatin proteins of the brain cells in rats]

The effect of protein extracted from nuclei of brain cells on the reaction of DNA-ethidium bromide complex interaction with DNAase I and Bac. subtilis nuclease was studied. The nuclei were isolated from the brain of Wistar male rats weighting 180-200 g. The fluorescence was recorded on a Hitachi MPF-44B spectrofluorimeter. Proteins extracted from the nuclei with 0.6 NaCl substantially inhibited the DNAase I but not Bac. subtilis nuclease activity. Other studied fractions of nuclei lacked the capacity for inhibiting DNAase I.