ENDOMETRIAL CATHEPSIN-D IMMUNOSTAINING THROUGHOUT OVULATORY AND ANOVULATORY MENSTRUAL CYCLES

The results of histological examination of the endometrium are normal in most patients with unexplained sterility, Cathepsin I) is a ubiquit ous lysosomal protease regulated by progesterone in the endometrium, A ssays of concentrations of cathepsin D might be useful in determining the functional responses of the endometrium to progesterone, To examin e this possibility, we quantified immunostaining of endometrial cathep sin D using an image analysis system in women with regular menstrual c ycles, An endometrial sample was obtained during the proliferative and luteal phases from 17 women with ovulatory menstrual cycles and at th e beginning and during the last 14 days of a cycle from 15 women havin g anovulatory menstrual cycles, In endometrial glands of ovulatory wom en, cathepsin D protein immunostaining increased during the cycle and was significantly higher during the luteal than during the proliferati ve phase [51 +/- 38.1 arbitrary units (AU) versus 118.2 +/- 58.9 AU; P < 0.01]. This increase was also observed in stromal cells, although t o a lesser extent(28.6 +/- 26.9 versus 41.5 +/- 43.1 AU; P = NS), In t he endometrium of women with anovulatory menstrual cycles, cathepsin D staining was high both for the proliferative and the luteal biopsies in glands (respectively 95 +/- 43 and 104 +/- 51.3 AU) and stromal cel ls (respectively 61.8 +/- 33.8 and 75 +/- 32.6 AU), In women with ovul atory cycles, cathepsin D staining was localized in the apical part of glandular cells during the proliferative phase and diffused throughou t the cytoplasm during the luteal phase, In contrast, in women with an ovulatory cycles, cellular localization of cathepsin D remained apical in glands, regardless of the day of biopsy, In conclusion, this study shows that the cytoplasmic localization of cathepsin D might be a qua litative biological indicator of endometrial gland responses to proges terone, This could be a useful tool for evaluating cell function, whic h is poorly tested by histology alone.