HYPERTHERMIA-INDUCED BY FREUNDS COMPLETE ADJUVANT IN RATS AS AN EXPERIMENTAL-MODEL OF SLIGHT PROLONGED FEVER

1. A single application of Freund's complete adjuvant (FCA) containing killed and dried Mycobacterium butyricum to adult male and female whi te rats led to the development of a hyperthermic response 2.5-3 h afte r injection. 2. The duration of the response in experimental animals d epended on ambient temperature. It lasted 1.5-2 days at 20-22 degrees C or higher while it was more prolonged at 14-16 degrees C. The hypert hermic response to FCA was not observed at temperatures below 10 degre es C. 3. The dynamics of the temperature response allows us to divide it into two phases. The first phase is characterized by an increase in body temperature exceeding the control value by 1.2-1.4 degrees C in the first day after injection. Then the response diminishes and subseq uently differs from the control by 0.4-1.0 degrees C, which leads us t o consider this phase as a slight prolonged fever (subfebrility).