Effects of hyperthermia on a neurogenic rat cell line (BT4C) in culture. Development of thermal tolerance during continuous heating.

The malignant neurogenic rat cell line BT4C developed tolerance to further heat injury after continuous heating in culture at 41.0 and 42.0 degrees C for 8 and 2 hours, respectively. Survival was evaluated by colony forming ability. The proliferative capacity of the surviving cells was reduced after heating as shown by a decrease in size of the colonies.