CHLORPROMAZINE-INDUCED HYPOTHERMIA IN TUMOR-BEARING MICE, ACUTE CYTOTOXIC DRUG LETHALITY AND LONG-TERM SURVIVAL

The acute lethality of various cytotoxic drugs (doxorubicin, vinblastine and nitrogen mustard) and long-term survival in a syngenic mouse-tumour system were studied at normal body temperature and at 28-degrees-C induced by chlorpromazine. Chlorpromazine-induced hypothermia itself neither caused acute toxicity nor influenced long-term survival. Doxorubicin (15mg/kg) and nitrogen mustard (6mg/kg) lethality was reduced at decreased temperature. The median survival time increased significantly from 35 days in normothermic to 52 days in hypothermic doxorubin-treated mice. With nitrogen mustard, no increase in long-term survival was seen in the hypothermic group. The acute lethality of vinblastine was enhanced by hypothermia and the long-term tumour survival was unaffected. Hypothermia or possibly anti-tumoural activity.