Effect of sodium nitroprusside on sperm motility, viability, and lipid peroxidation.
OBJECTIVE
To analyze the effect of sodium nitroprusside, a nitric oxide releaser, on sperm motion and lipid peroxidation-induced membrane damage in cryopreserved human sperm.


METHODS
Post-thaw, cryopreserved, human sperm samples were washed and divided into three aliquots. Each aliquot was incubated with either 0, 50, or 100 nM sodium nitroprusside.


METHODS
Samples were analyzed for lipid peroxidation (measured by malonaldehyde-thiobarbituric acid reactivity) at 3 hours post-thaw.


METHODS
Percent viability and motion parameters were assessed at 0, 10, and 30 minutes and 2, 3, 5, and 6 hours post-thaw.


RESULTS
All results represent a mean +/- SEM, n = 10. Lipid peroxidation in samples incubated with 50 nM sodium nitroprusside (15.1 +/- 2.1 nM malonaldehyde/10(8) sperm) or 100 nM sodium nitroprusside (13.2 +/- 2.1 nM malonaldehyde/10(8) sperm) was significantly lower than in controls (22.7 +/- 3.1 nM malonaldehyde/10(8) sperm). Percent viability was significantly reduced from 0 minutes (60.6% +/- 3.5%) to 6 hours post-thaw in controls (38.0% +/- 5.1%) but not in 50 nM (46.8% +/- 10.4%) or 100 nM (48.8% +/- 6.5%) sodium nitroprusside-treated samples. Compared with controls (18.3% +/- 3.4%), maintenance of percent motility at 3 hours post-thaw was significantly improved in 50 nM (24.5% +/- 2.9%) and in 100 nM (26.3% +/- 3.2%) sodium nitroprusside-treated samples. Straight line velocity maintenance was significantly improved in 50 nM (37.3 +/- 1.3) and in 100 nM (37.0 +/- 1) sodium nitroprusside-treated samples as compared with controls (30.5 +/- 1.7). Significant improvements in curvilinear velocity maintenance compared with controls (56.3 +/- 2.9) also were observed in 50 nM (65.9 +/- 2.1) and 100 nM (72.1 +/- 4.1) sodium nitroprusside-treated samples. Significant differences in the motion parameters of sodium nitroprusside-treated samples were maintained at 5 and 6 hours post-thaw in comparison to controls.


CONCLUSIONS
These results suggest that sodium nitroprusside is beneficial to the maintenance of post-thaw sperm motion and viability for up to 6 hours and that reduction of lipid peroxidative damage to sperm membranes may be the mechanism for these benefits.
Hellstrom
W J
WJ
Department of Urology, Tulane University School of Medicine, New Orleans, Louisiana 70112-2699.
Bell
M
M
Wang
R
R
Sikka
S C
SC
D002470:Cell Survival / Q000187:drug effects / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D006801:Humans; D015227:Lipid Peroxidation / Q000187:drug effects*; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism / Q000502:physiology; D009599:Nitroprusside / Q000494:pharmacology*; D013081:Sperm Motility / Q000187:drug effects / Q000502:physiology*; D013094:Spermatozoa / Q000166:cytology / Q000378:metabolism / Q000502:physiology*
D009599:Nitroprusside; D009569:Nitric Oxide; D008315:Malondialdehyde