Effect of voltage-gated sodium channels blockers on motility and viability of human spermin vitro

Objective:To test the effect of voltage-gated sodium channels (VGSCs) blockers on the motility and viability of human spermin-vitro and to evaluate the tested compounds as potential contact spermicidal.Methods: Sperm samples were obtained from healthy non-smoking volunteers of age 25-30 years who had not taken any drug 3 months before and during the course of the study. The effect of VGSCs blockers evaluated from two pharmacological classes including antiarrhythmic (amiodarone, procainamide and disopyramide) and antiepileptic (carbamazepine, oxcarbazepine, phenytoin, and lamotrigine) drugs. They were tested on thein-vitro motility and viability of human sperm using Computer Assisted Semen Analyzer.Results:All tested drugs except oxcarbazepine showed dose dependent inhibition of total motility with significant reduction (P<0.05) at the maximum concentration of 200 μM when compared with the control. The concentrations of drugs that reduced total sperm motility to 50% of control (half maximal inhibitory concentration) were 2.76, 14.16 and 20.29 μM for phenytoin, lamotrigine and carbamazepine, respectively;and 2.53, 5.32 and 0.37 μM for amiodarone, procainamide and disopyramide, respectively. The anti-motility effects were reversible to various degrees. There was statistically insignificant difference in the inhibition of sperm viability among amiodarone, procainamide and disopyramide. Phenytoin demonstrated the most potent spermicidal action.Conclusions:VGSCs blockers have significant adverse effects onin-vitro motility of human spermatozoa. Soin-vivo studies are required to determine their potential toxicological effects on human semen quality, which is an important factor regarding fertility. Moreover, these drugs have the potential to be developed into contact spermicidal.