Antimotility effects of Piper betele (L.) leaf extract on washed human spermatozoa

Polyvinylpyrrolidone (10,000 MW) co-precipimtc of dichloromethane: methanol (1: 1) extract of Piper betele (L.) (Piperaceae) leaves were investigated (N=12) for antimotility effects on washed human spermatozoa (up to 60 min. of incubation) using three parameters (percentage motility, average forward velocity and motility index). The concentration tested were 0.25, 0.5, 1.25, 2.5 and 5.0 mg/ml. The extract impaired these motility parameters in a dose related manner. The concentrations producing 50% inhibition were : percentage motility 0.47 ± 0.11 mg/ml, average forward velocity 0.37 ± 0.07 mg/ml and motility index 0. ± 0.02 mg/ml (mean ± s.e.m.). Futhermore the antimotility effects were irreversible and were not accompanied either with changes in the fluidity of-the plasma membrane (hypo-osmotic swelling test) or in the viability (nigrosin-eosin stain) of spermatozoa. The results suggest that potent antimotility agentls may be isolated from Piper betele (L.) leaves.