[Overacidified tissue and microcirculation (author's transl)].

A discussion of physiological fundamentals with respect to the inhibition of blood microcirculation in (tumor) tissue at reduced pH values around 6.0 is followed by a report on principles, design and results obtained with a light probe array which permits to determine in vivo reference values of the relative intensity of microcirulation in both normal and tumor tissues under various conditions. An analysis of the discussed records has shown that--as compared to a value of 80-66% without glucose infusion--the relative mean intensity of microcirculation in tumor tissue drops to approximately 8-4% about 300 min after the onset of glucose infusion under CMT administration at 37 degrees C. By adding the CMT step of hyperthermy, the relative mean intensity of microcirculation--compared to normal tissue at 37 degrees C--will further drop below 1%. With such a decline of microcirculation--and an adequate duration of, say, 8 hours--local hyperthermy at 41-42 degrees C is likely to cause a very pronounced damaging action on tumor tissue because the then noticeably reduced substrate offer proves to be insufficient to ensure the structure-maintaining metabolic rate of cancer cells.