The effect of hydrogen peroxide upon beta-adrenoceptor density and function in C6 rat glioma cells

Hydrogen peroxide has been suggested to play an important role in the patho genesis of Alzheimer's disease. In the present study, the effects of hydrog en peroxide upon the functional integrity of P-adrenoceptors have been inve stigated in C6 glioma cells. Treatment of cells for 24 h with hydrogen pero xide in serum-free medium produced a concentration-dependent cell toxicity, seen both using cell counting and LDH release into medium as end point. Th ere were no large nor consistent changes in either the density of cell surf ace beta(1), or beta(2)-adrenoceptors, measured using the hydrophilic ligan d [H-3](-)-CGP 12177, nor in either basal, forskolin and isoprenaline-stimu lated cAMP responses, following hydrogen peroxide treatment. It is conclude d that the decreased adenylyl cyclase activity and responsiveness to G(s) s timulation found in post-mortem brain samples from Alzheimer's disease auto psy cases is unlikely to be mediated by hydrogen peroxide. (C) 1999 Elsevie r Science Ltd. All rights reserved.