MICROCIRCULATORY EFFECTS OF HYPERTHERMIA AND 5-FLUOROURACIL IN THE SKIN OF NUDE-MICE

During cancer chemotherapy physical manipulation of skin perfusion by hyperthermia can limit therapeutic efficacy. Because it is important t o know microcirculatory responses to those forms of treatment, we used the ear of the lightly or not at all anesthetized nude mouse (mu/mu). To test, if whole body hyperthermia (WBH) and 5-fluorouracil (5-FU) a cutely affect skin microvessels, we applied red light (group I). 5-FU was injected prior to WBH, to test for effects of 5-FU on WBH (group 2 ). Respiratory rate increased and medium sized and small arterioles co ntricted during WBH in both groups and cutaneous perfusion decreased. 5-FU did not change these results. There were more leucocytes rolling along the vessel wall of small and medium-sized venules after 5-FU tre atment (compared to BL). Our data suggest that activation of sympathat ic tone by an external heat source compromises skin perfusion and coul d decrease the amount of cytostatic agents to that organ during WBH. F inally, there is more intense interaction among leucocytes and endothe lial cells omit in response to 5-FU.