EFFECTS OF HEATING RATE ON NORMAL AND TUMOR MICROCIRCULATORY FUNCTION.
Single vessel responses to hyperthermia were studied in tumor and healing subcutaneous tissues using a transparent access window chamber. Arterioles and venules, with diameters ranging from 15 to 150 mu were studied in both tissues. Rates of heating less than equivalent to 0. 68 degree C/min resulted in persistent normal arteriolar flow up to 45 degree C, but resulted in vascular stasis at a mean of 42. 5 degree C in tumor vessels. Mean times for stoppage of arteriolar flow were 45. 2 plus or minus 13. 1 and 25. 5 plus or minus 2. 6 min for each tissue, respectively, for a 0. 1 degree C/min heating rate.