Figure 2.
Effect of hyperammonaemia on energy metabolism in mice. (A) Mice were intraperitoneally administered 0 (circles), 100 (squares), or 200 mg/kg-BW (triangles) ammonium chloride, and blood ammonia was measured at 0, 10, 30, and 60 min after administration. (B–M) Ammonium chloride solution (AC, 100 mg/kg-BW) was administered intraperitoneally to BALB/c mice 3 times a week for 4 weeks. Energy expenditure in terms of locomotor activity (B,C), oxygen consumption (D,E), and respiratory exchange ratio (F,G) were measured by indirect calorimetry. Fat expenditure (H,I), carbohydrate (CHO) expenditure (J,K), and total energy expenditure (L,M) were calculated by using equations described previously38. Mean values for each time point are shown. Data are presented as mean ± s.e.m.; n = 3 mice per group (A), n = 8 mice per group (B–M). *P < 0.05, **P < 0.01 (Mann–Whitney U test).