Effects of treatment of marmosets with VEGF Trap for 10 days on thecal and granulosa cell proliferation (BrdU incorporation) in late secondary follicles. Note the high frequency of cell proliferation (arrows) in the thecal layer from control ovary (left panel) with much reduced frequency in the ovary from the treated animal (right panel). This indicates a suppression of endothelial cell and thecal cell proliferation. At this stage of development, there is no effect upon granulosa cell proliferation. Adapted from .