Early developmental differences in CRE expression in the Gnrh-cre and Lhrh-cre brains. Sagittal sections of Gnrh-cre and Lhrh-cre embryos were stained for CRE at embryonic day 11.5 (e11.5), e12.5, e13.5, and e17.5. Ant. brain, anterior brain; crib. plate, cribriform plate; hypo, hypothalamus. Images were taken at ×4, ×10, or ×20 as indicated in the figure.