The effect of non-convulsant doses of lindane on temperature and body weight.

The effect of lindane (gamma-HCH) on temperature, food intake and body weight was studied in male and female rats after single or repeated non-convulsant oral doses. A single dose of 30 mg/kg induced a significant decrease of core temperature (0.4 degrees C in males and 0.66 degrees C in females) 5 h after administration when compared to the control value. Lindane-induced hypothermia was strongly potentiated (1.45 degrees C) by cold stress when rats were kept at 4 degrees C. The same dose of lindane produced a significant decrease in body weight gain (-85% in males and -219% in females compared to the control gain), accompanied by a diminution of food intake, 24 h after administration. No decrease in both parameters was observed when alpha- or delta-HCH isomers 30 mg/kg were tested. After daily administration with 10 mg/kg lindane for 7 days, no hypothermic effects were observed. However, a slight but significant decrease in body weight gain was recorded over the treatment period. This effect was also accompanied by a reduced food intake. The observed stereoselective effects of HCH isomers on core temperature and body weight could be a useful model to study the mechanisms of lindane neurotoxicity at low subconvulsant doses.