Vitamin E deficiency alters the in vivo Rb+ discrimination of rat brain cortical cells

The in vivo Rb+ uptake and release of rat brain cortical cells of 11-months-old rats fed with a vitamin E deficient diet was investigated. The animals were treated with a daily dose of 30 mg RbCl/100 g body weight for 14 days. After discontinuation of the RbCl treatment the animals were killed at intervals of 2, 4, 9 and 15 days, respectively. The intracellular Rb+ and K+ contents were analyzed by energy dispersive X-ray microanalysis, whereas concentrations of these two ions were determined by atomic absorbtion spectrophotometry in the serum and cerebrospinal fluid. Vitamin E deficient rats accumulate more Rb+ than age-matched normally fed animals at any time taken into account. Rb+-discrimination ratios calculated on the basis of Rb+ and K+ contents of both, cortical cell cytoplasm and cerebrospinal fluid, are higher in vitamin E deficient rats than in the controls (+20%), which supports the view that the enhanced membrane lipid peroxidation induced by vitamin E deficiency impairs the passive membrane permeability for Rb+ (and K+).