Figure 1.

Endometrial hyperplasia in HSD17B1TG females. Endometrial hyperplasia was observed in HSD17B1TG females at the age of 4 months: hyperplastic glands growing inwards and normal luminal epithelium (A), hyperplastic glands growing inwards and nuclear atypia of the luminal epithelium (B), wild-type endometrium at proestrous, which corresponds to the human proliferative phase (C), wild-type endometrium at diestrous, which corresponds to the human secretory phase (D). The sites of the inserts are shown with dash-lined boxes. The expression of a proliferation marker PCNA in hyperplasia without atypia (E), atypical hyperplasia (F), and normal wild-type (G) at proestrous and diestrous. Examples of PCNA-positive cells are indicated by arrows. HSD17B1TG females presented with anovulatory ovaries lacking CLs (H), whereas CLs were abundant in the ovaries of the wild-type littermates (I). CL = corpus luteum.