Figure 2

Increased circulating levels of IGF-I had no effect on pubertal mammary gland growth. Representative whole mounts of wild type (wt) and IGF-I transgenic (TTR-IGF-I) mammary glands at 4 wks (top 2 panels), 6 wks (middle 2 panels), and 9 wks of age (bottom 2 panels). N = 20 per group at 4 wks of age; N = 4 for WT and N = 7 for TG at 6 wks of age; N = 7 for WT and N = 8 for TG at 9 wks of age. WT = wild type and TG = TTR-IGF-I.