Visible Light Reverts the Effect in Motility Produced by Temperature in Mouse Sperm.

The effects of visible light on biological systems have been studied for several years, from mammal spermatozoa motility to protein structural changes. The data have shown that these systems interact in certain ways with light but the origin and mechanisms are still far from being understood. Thus more work on the subject is needed. In the present work we study the effects of green light (490-540 nm) on the motility of mouse spermatozoa with an optical technique of time-resolved correlation adapted to study several samples simultaneously. Image correlation analysis is used to follow the temporal behavior of the sperm samples at 10 degrees Celsius and 37 degrees Celsius . At these contrasting temperatures, the motility is radically different: at the lower one the prevalence is the lengthiest, according to a previous finding reported by us. Our present results show that while green light extends the prevalence of sperm motility at 37 degrees Celsius, it reduces it at 10 degrees Celsius. This evidence suggests that green light is playing an important role in the spermatozoa motility. We speculate about the possibility that these opposed effects are related to elastic changes that spermatozoa suffer during irradiation.