THE EFFECTS OF OESTROGEN AND PROGESTERONE ON UTERINE CELL DIVISION AND EPITHELIAL MORPHOLOGY IN SPAYED, ADRENALECTOMIZED RATS

Abstract

Progesterone alters the mitotic and morphological responses of the mouse uterus to oestradiol-17β (Martin & Finn, 1968; Martin, Finn & Carter, 1970). The following experiment was done to see if the same effects occurred in the rat and whether or not the adrenal glands were necessary. Forty female Sprague—Dawley rats (200–300 g) were spayed under sodium pentobarbitone anaesthesia. Twenty were also adrenalectomized and given 1% NaCl solution to drink. One week later all the animals were primed with three daily s.c. injections of 1 μg oestradiol-17β in arachis oil. After 2 days without treatment the animals were divided into groups and given the hormones shown in Table 1. 21 h after the last injection, each animal was given 0·75 mg demecolcine (Colcemid, Ciba) s.c. in water and killed 4 h later. At autopsy the success of adrenalectomy was checked visually. One horn of each uterus was fixed overnight in formol