Dj. Honess et al., PENTOXIFYLLINE INCREASES RIF-1 TUMOR PO(2) IN A MANNER COMPATIBLE WITH ITS ABILITY TO INCREASE RELATIVE TUMOR PERFUSION, Acta oncologica, 34(3), 1995, pp. 385-389
The time course and dose response of 600 mm(3) subcutaneous RIF-1 tumo
urs to pentoxifylline was measured in terms of relative tumour perfusi
on, assayed by Rb-86 extraction, and pO(2) distribution measured by th
e Eppendorf histograph. Both perfusion and pO(2) distribution were max
imally increased by 20 mg/kg pentoxifylline 15 min after administratio
n, perfusion to 141 +/- 15% (2 SE) of control, and median pO(2) from 3
to 15 mmHg, with the percentage of values < 2.5 mmHg falling from 44
+/- 8% to 22 +/- 7%. Fifteen minutes after administration the pO(2) in
creases were linearly dose-dependent up to 20 mg/kg. Correlation coeff
icients for perfusion data with the percentages of low values were, fo
r time course and dose response data respectively, 0.76 and 0.84 for m
edian pO(2), 0.84 and 0.97 for percentage < 2.5 mmHg and 0.81 and 0.87
for percentage < 10 mmHg, The data show good correlation between chan
ges in perfusion and pO(2) distribution parameters, with better correl
ation for percentage of low values than for median pO(2).