Possible mechanisms in Ficus exasperata ethanol root fraction amelioration of lead-induced corpus cavernosal contractile impairments in male Wistar rats.

Abstract

Background:Lead exposure is reported to cause impaired male reproductive tract functions often due to elevated oxidative species. F. exasperata leaf extract contains potent phyto-antioxidants with beneficial endothelial functions. Objectives: This study investigates the effect of ethanolic extract of F. exasperata (EEFE) treatment on the corpus cavernosal contractile activity in lead-exposed adult male Wistar rats. Materials & Methods: Corpus cavernosum strips (CS) were excised from control, EEFE only treated (400 mg/kg), lead + EEFE treated and lead only treated (100 mg/kg) male Wistar rats. Cumulative contractile responses of CS to acetylcholine, potassium chloride, and calcium influx were determined. Furthermore, cumulative dose responses to acetylcholine after incubation in LNAME, indomethacin, nifedipine, and acetovanillone were also determined by measuring isometric contractions using Ugo Basile data capsule acquisition system. Results: Relaxation(%) response to cumulative doses of acetylcholine (10-9–10-5 M) was enhanced in EEFE only treated (59%) compared to lead only (45%). Contractile response to KCl (10-60 M) was restrained in control and EEFE cotreated when compared to lead only treated. Preincubation of the CS with nifedipine (10-4 M) suppressed the relaxation(%) in the lead + EEFE co-treated. Preincubation of the CS in indomethacin improved the relaxant response(%) of the CS in EEFE only and lead + EEFE co-treated (53.53% ±2.80 & 54.65%± 2.95 respectively) compared with the lead only treated (45.40%±1.79). Preincubation with L-NAME significantly reduced relaxation response(%) in EEFE only treated group. Relaxation response(%) of the CS was enhanced in the lead + EEFE group after preincubation with acetovanillone. Conclusion: The study suggests that L-type and voltage-gated calcium channels, NO, and potent antioxidant activity, are important in EEFE amelioration of lead-induced contractile impairments.