The contraceptive effect of a novel filtering-type nano-copper complex/polymer composites intra-vas device on male animals.

Contraceptive techniques which target vas deferens have been paid great attention for their good efficacy, safety and reversibility. We have made a filtering-type intra-vas device (IVD) using nano-copper complex/polymer composites. Twenty male adult Beagle dogs and 40 male rabbits were randomly assigned to four groups (sham-operation, IVD, reversal and vasectomy groups). Dogs' semen parameters, concentration of α-glucosidase, copper and zinc ions were tested pre-operation and 1, 3, 6 and 12 months post-operation. The pregnancy rates of the rabbits were evaluated by mating trials after the IVDs were implanted. The histology of testis, epididymides and vas deferens of the animals was examined using an electron microscope. Apoptosis of the cells in the testes, epididymides and vas deferens was detected by TUNEL method. There was no sperm in the semen of dogs, which had been inserted IVD and vasectomized at 1, 3, 6 and 12 months post-operation. The concentration of α-glucosidase in the IVD group, reversal group and sham-operation group was not significantly different between pre- and post-operation. The pregnancy rates of the female rabbits in the vasectomy, IVD and reversal groups were all zero, but the pregnancy rate in the reversal group, after taking out IVD, and that of the sham-operation group was 60% and 80%, respectively. The ultrastructures of the testes, epididymides and vas deferens of the male animals in the IVD group and sham-operation group were in normal ranges compared with the vasectomy group. The apoptosis of the cells in the testes, epididymides and vas deferens in the vasectomy group of both dogs and rabbits was obvious compared with the other groups. No significant changes in the quantities of copper and zinc ions were found in semen of the male dogs both pre- and post-operation. Our studies demonstrated that the filtering-type nano-copper complex/polymer composites intra-vas device may be an efficacious, safe and reversible male contraceptive device.