Effect of repeated administration of the small compounds on peripheral blood cell levels in neutropenic CD rats. Male CD rats were injected intraperitoneally with 25 mg/kg CPA on day 0 (arrowhead), and thereafter treated subcutaneously with SSCL02446 nitrate (panel A), SSCL02447 nitrate (panel B), SSCL02448 nitrate (panel C), or rhG-CSF (panel D) on 4 consecutive days (days 1-4), and neutrophil counts were measured in peripheral blood. The arrows indicate the times of administration of small compounds and rhG-CSF. On day –2 and days 1, 2, 3, 4, 5, 6, and 8, peripheral blood cells were collected. On days 1, 2, 3, and 4, they were collected 8 hours after each administration. Each point represents the mean of counts on 4 or 5 rats ± SEM. Blood smears from each group were stained with Diff Quik, and differential counts were performed as described in “Materials and methods.” Significant differences (*P < .05; **P < .01) from vehicle control were assessed by Dunnett test.