[Collagen synthetic activity in rabbit ovary during ovulation and its blockage by indomethacin]

In order to investigate the possibility of the participation of prostaglandins (PGs) in the collagen synthetic activity during the ovulatory process, we measured prolyl hydroxylase (PH) activity and the hydroxyproline (Hyp) content of ovarian follicles in rabbits after the administration of hCG and indomethacin (IM). The minimum dose of IM (4mg/kg) effective in blocking ovulation was given simultaneously with hCG to mature female Japanese white rabbits. PH activity in the ovary reached its peak level at 13hr after the hCG injection, immediately after ovulation. This increase was not observed in other tissues such as skin, aorta or ear obtained from ovulating rabbits. In the IM-treated rabbits in which ovulation was blocked, PH activity was rather suppressed and did not show any prominent peaks, although IM did not directly suppress PH activity in the in vitro assay system. The amount of Hyp did not show any significant changes during the ovulatory process or during ovulation blockage by IM. It is suggested that PGs play an important role in controlling collagen synthetic activity of the ovary through the ovulatory process.