Lipid peroxidation and ascorbic acid status in respiratory organs of male and female freshwater catfish Heteropneustes fossilis exposed to temperature increase.

Lipid peroxidation and ascorbic acid (AsA) contents were measured in the gill and air sac of male and female catfish, Heteropneustes fossilis, after exposure to temperatures (25-37 degrees C) at various times. Lipid peroxidation in gill and air sac biomembranes was enhanced on increasing the temperature from 25 to 37 degrees C for 60-240 min. In gill, the significant decline in AsA was observed only at 240 min exposed with different temperature range. In other exposure periods, the decline was nonsignificant. Air sac AsA was decreased significantly by exposure of 32 and 37 degrees C temperatures at various times. Lipid peroxidation and AsA contents after temperature exposure in gill and air sac of male and female fish showed no significant difference. The findings indicated an increased oxidative stress in gill and air sac of male and female fish after increased temperature exposure. The decline in AsA level supports its antioxidant role in relation to oxygen radicals.