Human sperm motility--enhancement and inhibition measured by laser Doppler spectroscopy

Laser Doppler spectroscopy is an excellent instrument to measure motility parameters of human spermatozoa. Experiments have been performed by the aid of a now commercially available instrumental setup called LAZYMOT to study enhancement and inhibition as well as influences of different physical treatments on the motility of human spermatozoa. The motility enhancing influence of Kallikrein (up to 40% with 4 KU/ml) and prostaglandin E2 could be proven, thereby verifying some sort of mechanism of action within the Kallikrein-Kinin system. Furthermore tested substances in this context were bradykinin (no effect), caffeine (enhancement), salicylic acid (slight decrease), and other prostaglandins (no effect). The influence of washing, centrifugation, resuspension liquid, and temperature has been examined. It turned out that the lowest motility degradation is to be achieved by washing twice at a pH value of 7.4 at forces of 200 g for 10 min each time. The optimal temperature during this process and the measurements thereafter was found to be 36 degrees C. Unsaturated fatty acids like arachidonic acid have been found to be very strong motility inhibiting substances, which can totally block any movement of spermatozoa.