Effect of postnatal age after IUGR on RAR protein isoform relative abundance in homogenates of rat lung tissue. Results are shown as mean ± SD for n=4/group. White fill indicates male control, black fill indicated male IUGR, grey fill indicates female control and hatched fill indicates female IUGR. Panel a: RARα protein abundance for male pups, left side and female pups, right side. Panel b: RARβ protein abundance for male pups, left side and female pups, right side. Panel c : RARγ protein abundance for male pups, left side and female pups, right side. At P21 (Panel c, left side), RARγ protein abundance was significantly greater in IUGR male pups than male control pups. The other differences occurred at P0 in IUGR female pups (Panel a, right side). RARγ protein abundance was significantly lower in former IUGR female pups than in control female pups. Also at P0, RARα protein abundance was significantly higher in former IUGR female pups than in control female pups. †Different from P0 (p<0.05). § Different from P6 (p<0.05). *Different from age and sex-matched IUGR (p<0.05). Non-parametric statistical tests were used (see Methods section).