HYDROXYL RADICALS AND NITRIC-OXIDE IN NEUROTOXICITY AND NEUROPROTECTION

In the light of both neurodestructive and neuroprotective properties o f nitric oxide, we have analysed the influence of hydroxyl radicals in these actions of nitric oxide. Requirement of superoxide anions to ge nerate the neurotoxic peroxynitrite and the fact that it decomposes to form the more cytotoxic hydroxyl radicals at physiological pH, indica te the active involvement of the latter molecule in the neurotoxic act ion. Recent evidences also indicates that nitric oxide can act as an a ntioxidant in vitro and in vivo. Hence, it is suggested that it is tim e for a critical in vivo analysis of this molecule during a number of neurotoxic events to conclusively establish its role in neuroprotectio n and/or neurotoxicity. (C) 1998 Published by Elsevier Science B.V. Al l rights reserved.