The effect of relaxin and ubiquitin on sperm motility.

Ubiquitin and relaxin--2 low molecular weight substances--have different effects on sperm motility. These two compounds are not separable by chromatographic procedures. Ubiquitin in different concentrations had no effect on 4 parameters of sperm motility, as evaluated by the Lazymot analyser. However, relaxin at a concentration of 1.99 pmol inhibited all 4 parameters of sperm motility compared with saline, Taumild or ubiquitin.