Effect of X Irradiation (0.6-2.4 KR) ON Cation Activated Atpases from Subcellular Fractions of Rat Brain

摘要

A small significant increase in the activity of a purified ATPase stimulated by (Na(+) + K(+)) was demonstrated at doses of 0.6 to 2.4 kR. Regression analysis indicates a curvilinear radiation effect; with a significant plateau at doses above 1.2 kR. After 1200 R, a decrease of this same enzyme activity was noted when the more reactive sylfhydryl groups were blocked with n-ethylmaleimide. Only the activity stimulated by Na(+) + K(+) was significantly affected by irradiation. Further fractionation of the enzyme complex indicated that a lipid band in the Ficoll gradient isolation was sensitive to 1200 R. Although this effect was not noted in vivo, it was considered that much of the enzyme could be rapidly repaired in vivo. Radiation damage to such constituents of a membrane system would explain many neurological radiation effects. (Author)