Mechanisms of Ageing and Development 97 (1997) 215–226 Aging and detoxifying enzymes responses to hypoxic or hyperoxic treatment Fernanda Amicarelli a , Carmine Di Ilio b , Loredana Masciocco a , Antonella Bonfigli a , Osvaldo Zarivi a , Maria Regina D’Andrea c , Camillo Di Giulio d , Michele Miranda a, * a Department of Basic and Applied Biology, Uniersity of L’Aquila, ia Vetoio 10, I -67010 Coppito, L’Aquila, Italy b Institute of Biochemical Sciences, Uniersity of Chieti, Chieti, Italy c Istituto Superiore per l’Educazione Fisica di L’Aquila, L’Aquila, Italy d Institute of Physiology, Uniersity of Chieti, Chieti, Italy Received 16 November 1996; received in revised form 9 March 1997; accepted 12 March 1997 Abstract We studied the levels of antioxidant and detoxifying enzymes in the livers and lungs of young and old rats kept under hypoxic or hyperoxic conditions as models of oxidative stress. In particular, we investigated the levels of enzymes directly involved in active oxygen species scavenging (superoxide dismutase, catalase and glutathione peroxidase – selenium dependent) and enzymes challenged with detoxification processes (glutathione transferase, glyoxalase I and glutathione reductase) in order to obtain a wide comparative view of the defence strategies used with respect to the age of the animals. The results show that the responses of some protective enzymes in young rats are opposite to those of old ones. Some of the changes found appear mainly due to age, while others appear to be due only to the oxygen tensions and are independent of the aging process. The glutathione contents of the liver and lung from young and old rats under hypoxic and hyperoxic conditions were measured. © 1997 Elsevier Science Ireland Ltd. Abbreiations: GSH, reduced glutathione; GSSG, oxidized glutathione. * Corresponding author. Tel.: +39 862 433262; fax: +39 862 432373; e-mail: Miranda @AXSCAQ.AQUILA.INFN.IT 0047-6374/97/$17.00 © 1997 Elsevier Science Ireland Ltd. All rights reserved. PII S00 7-6374(97)00061-4