[Molecular-biological studies of the cervical secretion with one-dimensional electrophoresis]

In the present study the polypeptide composition of cervical mucus was analysed during the human menstrual cycle. Changes in the polypeptide profile as displayed by a very sensitive silverstaining method were consistent with cycle dependent variations in observed rheological properties of the mucus and activities (concentrations) of luteinising hormone (LH) (from comparatively analysed blood). It could be shown that whereas three main polypeptide components of the mucus (50 kd [kilodalton], 14 kd, 12 kd) remained constant the amount and intensity of other polypeptides increased towards midcycle (ovulation) and diminished on the days after ovulation. A 25 kd polypeptide (being a main component on the days before ovulation) disappeared at midcycle (on the day of ovulation). On the same day a new main peptide (8 kd) was observed, which was decreasing (in favour of the 25 kd peptide) on the days after ovulation. It is postulated that the described shift in the polypeptide pattern of the cervical mucus may be a result of the degradation of the light chain of IgG at midcycle.