Effects of intratesticular injection of zinc-based solution in rats in combination with anti-inflammatory and analgesic drugs during chemical sterilization.

Aim: Chemical sterilization is a non-surgical method of contraception based on compounds injected into the testis to induce infertility. However, these injections can cause discomfort and pain able to impair the recovery of animals after this treatment. The objective of this study was to investigate if anti-inflammatories or pain relievers inhibited the sterilizing effect of zinc gluconate-based solution on the testis.

Materials and Methods: Adult rats were treated in groups: G1 (control), G2 (dimethyl sulfoxide + dipyrone); G3 (dipyrone/zinc); G4 (dipyrone + celecoxib/zinc); G5 (dipyrone + meloxicam/zinc), and G6 (dipyrone + dexamethasone/zinc) in a single dose per day during 7 days. Animals were analyzed at 7, 15, and 30 days after treatments.

Results: The zinc-induced a widespread testicular degeneration and decreased testosterone levels even in combination with anti-inflammatories or pain relievers. Testis, epididymis, prostate, and seminal vesicle had a weight reduction. The anti-inflammatory effect of dexamethasone interfered in the desired action of zinc gluconate in the 1st 15 days and celecoxib up to 7 days.

Conclusion: Meloxicam plus dipyrone did not impair the chemical sterilization based on zinc gluconate, and it can be used to reduce nociceptive effects in animals after chemical sterilization.