In vitro effect of some free estrogens or estrogen precursors on collagenase activity of uterine cervix.

In order to determine whether or not collagenase activity of the uterine cervix can be influenced by estrone (E1), estradiol (E2), estriol (E3), equilin, dehydroepiandrosterone sulfate (DHA-S) or dehydroepiandrosterone (DHA), the collagenase activity of extract of connective tissue of the uterine cervix treated with the drug was measured. A higher collagenase activity was obtained in pregnant cervix than that in nonpregnant ones. There was no difference in collagenase activity of the uterine cervix extract between control and drug (5 X 10(-5) M of E1, E2, E3, equilin, DHA-S or DHA) groups both in nonpregnant and pregnant conditions. After preincubation of tissue with 1 X 10(-5) M of the said drug at 37 degrees C for 60 min, the enzyme activity of the supernatant was also investigated. In nonpregnant conditions, no increase in the enzyme activity was observed. On the contrary, significant increase of the enzyme activity was obtained in pregnant uterine cervix preincubated with equilin, E3, DHA-S or DHA comparing to that of control group. However, this increase was not observed by E1 or E2. Elastase activity was also investigated on cervical connective tissue both in nonpregnant and pregnant conditions. No increase in elastase activity was observed in the pregnant cervix comparing to that of nonpregnant group.