Histologic changes in the RARα antisense mice as compared with normal littermates. Sections of skin of normal (A) and transgenic (B) mice showing significant atrophy and degeneration in pilosebaceous units (arrowhead) in transgenic mice (B) as compared with normal mice (A). (C) and (D) are sections from normal and transgenic mice, respectively. Poor order of spermatogenesis (arrow) and few spermatozoa are seen in the seminiferous tubules of transgenic mice as compared with those of normal mice. Sections of epididymides of normal (E) and transgenic (F ) mice show marked squamous metaplasia (arrow) in transgenic mice, but pseudostratified epithelium in normal mice (arrow).