Figure 1.

VO₂ (mL/kg/Min) plotted at 1-hour intervals of male Ames dwarf (a), GHRKO (b), and bGH TG (c) mice and their normal siblings (n = 8–10 per phenotype). VO₂ in the long-lived Ames dwarf (F = 235.5) and GHRKO (F = 326.5) mice was significantly increased compared with their normal siblings, whereas the bGH TG (F = 26.40) mice showed decreased VO₂ compared with their normal siblings. The bar graph (d) illustrates daily VO₂ from all mice with all time points compiled into daily averages and expressed as percent of normal control. Data reported are means ± standard error of the mean. Note: bGH TG = bovine GH-overexpressing transgenic; F = F statistic; GHRKO = growth hormone receptor knockout; VO₂ = oxygen consumption; ***, significantly different (p < .001).