Effect of Step-up and Step-down Hyperthermia on Skin of Mice

Choi, Ihl Bohng; Kim, Choon Yul; Bahk, Yong Whee

Abstract

The usefulness of hypertemie for cancer therapy have well been established. The purpose of the present investigation was to ascess the effect of step-up (42 degrees C -> 44 degrees C sequence ) and step-down (44 degrees C -> 42 degrees C sequence) heating on the skin of the hind foot of the mouse. Hyperthermic treatments were given by immersion the hind foot of the mouse in circulating water baths. Skin response was studied by the leg reaction, which was scored according to a numerical scoring system proposed by Urano et al (1980). The results were as follws 1.The sking damage of 44 degrees C control group was more severe than 42degree C control group (p<0.0.5), except for 15min. heating group. 2. The skin damage of step-down group was more severe than step-up group (p<0.0.5). 3. The skin damage of 44 degrees C control group was more severe than step-up group when there is no difference in 44 degrees C heatingtime of step-up group from 44degree C control group (p<0.0.5). 4. In step-down group, the skin damage was more severe than 44degree C control group after preheating 45 min at 44 degrees C (p<0.0.5). Therefore, the above findings suggest the normal tissue damaged by step-up heating was correlated with heating time of post step-up. The dropping of heating temperature in late phase had more severe damage of the skin than that in early phase during hyperthermia, and so contineous control of satisfactory temperature should be considered as the one of the most important factor for prognosis, complications of clinical hyperthermia