O2 consumption and CO2 release in 3 groups of awake rats were studied on a MM-100 metabolic monitor system (CWE Inc.). The animals of 2 groups were preadapted to 4-h maintenance in special boxes (2 weeks). The rats could perform rotational movements and limited movements in the rostrocaudal direction (hypokinesia). The animals of one group were daily exposed to 4-h antiorthostatic load (≤45°) for 2 weeks. After 2 weeks, the intensity of metabolism in rats with antiorthostatic hypokinesia was lower than in hypokinetic specimens (by 15–20%, p<0.05) and freely moving animals (by 20–25%, p<0.05). Interleukin-6 concentration in rats with antiorthostatic hypokinesia (0.25±0.09 pg/ml) was lower than in hypokinetic (4.01±0.57 pg/ml) and freely moving animals (3.69±0.56 pg/ml). The decrease in the concentration of a proinflammatory cytokine interleukin-6 during experimental antiorthostatic hypokinesia reflects inhibition of metabolic processes, which are activated during antiorthostatism (but not hypokinesia).