Abstract. The incorporation of proline, a precursor for collagen specific hydroxyproline, is regarded to reflect the metabolism of collagen. In vitro experiments were carried out to investigate the influence of sex steroids on the incorporation of [3H]proline into the human follicular wall. Tissue pieces from the apical wall of follicles at different stages of development were incubated in the presence of the steroids and [3H]proline, and the tissue bound radioactivity was determined.
Progesterone induced a decrease of radiolabelling in both unripe and pre-ovulatory follicles. Androstenedione caused a similar effect but only in pre-ovulatory follicles. The influence of oestradiol-17β on the incorporation of [3H]proline was less pronounced with a tendency towards a decrease of radiolabelling in both types of follicles.
It is suggested that the observed biochemical changes induced by sex steroids are of importance for connective tissue remodelling preceding human follicular rupture.