The effects of HCG, indomethacin, flufenamic acid and aspirin in the immature female rat.

Immature female rats (21 to 23 days old, 35 to 45 g) were injected subcutaneously with 2-5 i. u. HCG 18 hr before autopsy. Ovaries and uteri were removed; wet weight, dry weight and uterine protein content were determined. Ovarian and uterine weights, ovarian blood volume and uterine protein content were increased after HCG treatment. When immature female rats were pretreated with indomethacin, flufenamic acid or aspirin, the ovarian effects of HCG were inhibited: only slight increases in ovarian weight and blood volume were observed. Indomethacin attenuated the increases in uterine weight, and protein content, but neither flufenamic acid nor aspirin were effective in inhibiting these responses. The possible role of prostaglandins and of oestrogen as mediators of these responses is discussed.