| Abstract: | The organic solvents methanol and ethanol at concentrations of 2.5% and 5% (v/v), respectively, were found to significantly (P < 0.001) decrease the radius of curvature and track velocity of S. commercialis sperm. To observe the effects of the solvent directly on the axoneme, S. commercialis sperm models were prepared by extraction with Triton X-100 and reactivation with ATP in media containing acetate anions, DTT, magnesium, and cAMP. Concentrations of 0.1% Triton X-100 demembranated sperm while 0.01% and 0.05% Triton X-100 permeabilized sperm. Sperm models were successfully produced after reactivation with 1 mM ATP. At pH 8.25, 1% (v/v) ethanol or methanol was observed to increase waveform asymmetry and significantly (P < 0.001) decrease track velocity of 0.1% Triton X-100 demembranated sperm models. Similarly 1% (v/v) ethanol increased tailwave asymmetry and decreased track velocity of 0.01% and 0.05% Triton X-100 permeabilized sperm models. Reactivated motility of 0.05% Triton X-100 permeabilized sperm models prepared at pH 7.8 were poor and improved after treatment with 7% (v/v) ethanol, which increased waveform asymmetry and doubled the track velocity of sperm. This stimulatory effect of ethanol was unchanged in the presence of the alcohol dehydrogenase inhibitor pyrazole. Concerning the precise mechanism of action of ethanol on the axoneme, we conclude that a stimulatory or inhibitory effect of ethanol is dependent on the pH of the sperm model system used. |
