The effect of copper on spermatozoal motility and viability evaluated objectively with the aid of the multiple-exposure photography method

Human spermatozoa motility analysis in a Ringer's solution containing cupric ions

The ability of cupric ions to immobilize human spermatozoa was assessed in vitro using an optical microscope. A Ringer's solution containing human spermatozoa and three cupric ion concentrations of 8 x 10(-8) mol/L, 8 x 10(-6) mol/L and 8 x 10(-5) mol/L were tested. The higher cupric ion concentrations (8 x 10(-5) mol/L and 8 x 10(-6) mol/L) significantly reduced spermatozoa motility after about 20 min. However, with the lower cupric ion concentration tested (8 x 10(-8) mol/L), also for 20-min experimentation, the reduction in motility was more limited.

The influence of different copper wires on human sperm penetration into bovine cervical mucus, in vitro

The influence of four different copper-containing intrauterine devices (IUD) (Nova-T, Multiload, Fincoid 250 and copper-T 250) on the penetration of human sperm into bovine cervical mucus were assessed. Pooled samples of predetermined sperm concentration were suspended in Earl's medium in which a copper IUD was previously incubated for periods between one hour to fourteen days. The mean copper concentration was determined for each of the medium containing IUD and was found to be between 284 +/- 93 micrograms/100 ml to 392 +/- 138 micrograms/100ml. While there was no adverse effect on sperm motility by the copper-containing medium, there was a significant reduction in the number of sperm penetrated into the bovine cervical mucus as compared to the penetration of sperm suspended in pure Earl's medium. It therefore seems that the influence of copper on sperm penetration might be by an effect on the environment or spermatozoal migration rather than by direct effect of copper on sperm motility.

Toxicity and uptake of heavy metals by human spermatozoa

The effects of metallic copper on human spermatozoa are described. Incubation with the metal caused a fall on the percentage of motile sperm, which was directly related to the surface area of copper employed and to the copper content of whole semen. These changes were accompanied by a decrease in semen zinc levels and an uptake of copper by individual sperm cells, as determined by X-ray microanalysis. Low concentrations of ionic copper caused a less marked fall in sperm motility, although the metal was generally more toxic than zinc or cadmium ions. All three metals were accumulated by spermatozoa on incubation, with cadmium causing a decrease in sperm nuclear zinc concentrations.