Correlation between steroids and plasmin in rat ovaries during ovulatory process.

Progesterone (0.5 mg/rat) and estradiol-17 beta (10 micrograms/rat) injected(im) to adult female albino rats on the morning of proesterous significantly enhanced the ovarian plasmin activity as measured by the fibrin plate method at the time of ovulation which was confirmed to be at 2.30 a.m. by estimation of ovarian plasmin activity at definite intervals before and after ovulation. The ovarian plasmin activity showed a gradual increase towards ovulation and reached a maximum level at 2.30 a.m. and again decreased after ovulation. However, the nonsteroidal estrogen antagonist, tamoxifen induced inhibitory effects on the ovarian plasmin activity as compared to control and estradiol-17 beta treatment. Thus these studies reveal a positive relationship between steroids and the ovarian plasmin activity during ovulation.

Effect of steroids on ovarian neutral proteinases during ovulation in cyclic albino rats.

Progesterone (0.5 mg/rat) and estradiol-17 beta (10 micrograms/rat) injections (im) on the morning of proestrous in cyclic female rats enhanced the ovulation rate (number of ova shed). These steroids also significantly (P less than 0.05) increased the activity of ovarian neutral proteinases, observed on the morning of estrus as compared to those in control and vehicle treated animals. Nonsteroidal estrogen antagonist, tamoxifen suppressed ovulation rate and ovarian neutral proteinase activity as compared to control, its vehicle and steroidal treatment. The results demonstrate a stimulatory effect of progesterone and estradiol 17 beta on ovulation and ovarian neutral proteinases.