GLUCOSE-INDUCED THERMOGENESIS IN PATIENTS WITH SMALL-CELL LUNG-CARCINOMA - BEFORE AND AFTER INHIBITION OF TUMOR-GROWTH BY CHEMOTHERAPY

Seven weight-losing patients with histologically verified small cell l ung carcinoma were given an oral glucose load of 75 g before and at le ast 3 weeks after the end of chemotherapy to examine the effect of glu cose on whole body and skeletal muscle thermogenesis before and after reduction of tumour. Whole body energy expenditure was measured by the open circuit ventilated hood system. Forearm blood flow was measured by venous-occlusion strain-gauge plethysmography. The uptake of oxygen in skeletal muscle was calculated as the product of the forearm blood flow and the difference in a-v oxygen concentration. Whole body resti ng energy expenditure (REE) did not increase, it was 4-4 +/- 0.3 kJ mi n-1 (mean +/- SE) before chemotherapy and 4.4 +/- 0.2 kJ min-1 after c hemotherapy. The glucose-induced thermogenesis in the 180 min followin g the glucose load was 93.6 +/- 9.9 kJ 180 min-1 before chemotherapy. This is significantly increased compared to that found in a healthy co ntrol group (74.7 +/- 4.8 kJ 180 min-1, P<0.02). The glucose-induced t hermogenesis was significantly reduced to 47.7 +/- 10.2 kJ 180 min-1 ( P<0.05) after chemotherapy. The oxygen uptake in resting skeletal musc les was 6.9 +/- 0.3 mumol 100 g-1 min-1 before chemotherapy and 7.0 +/ - 0.7 mumol 100 g-1 min-1 after chemotherapy. This did not increase du ring the first 90 min following the glucose load in either investigati ons. In the period 90-180 min following the glucose load, the oxygen u ptake was significantly increased before chemotherapy as compared to a fter chemotherapy, which suggests that the reduced whole body thermoge nesis after chemotherapy in part was due to reduced skeletal muscle th ermogenesis.