Fig. 4.

Phenotypic characterization of Pgr^ΔE3 null female rats. (A) Examination of acute uterine responses to progesterone in wild-type (+/+) and Pgr^ΔE3 null (−/−) rats. Progesterone-responsive transcripts were monitored by qRT-PCR (n = 6/group). Results are presented as the mean ± SEM. Different letters above bars signify differences between means (P < 0.05). (B) Representative estrous cycle profiles of Pgr^ΔE3 null females. Estrous cycles were monitored for 7 wk by daily inspection of vaginal cytology (D, diestrus; P, proestrus; E, estrus). The graphs also indicate when males were introduced. Red points indicate the presence of sperm in the vaginal lavage.