title: Comparison of motility and membrane integrity to assess rat sperm viability.
abstract: Rat sperm motility and membrane integrity were compared as endpoints for viability. Sperm motility was measured by computer-assisted semen analysis (CASA), whereas membrane integrity was assessed by flow cytometric analysis of sperm stained with two nucleic acid stains, SYBR-14 and propidium iodide. The two techniques were compared in experiments that examined sperm viability over time and by analysis of known mixtures of control and freeze/thaw-killed sperm. Results from the two approaches were quantitatively very similar. Sperm from rats treated with dibromoacetic acid (600 or 1200 mg/kg) or alpha-chlorhyrin (100 mg/kg) were also analyzed. Neither technique detected a treatment-related effect with dibromoacetic acid. CASA identified a significant decrease in sperm motility in alpha-chlorhyrin-treated rats, whereas flow cytometric analysis did not find a measureable change in sperm membrane integrity. Because decreases in sperm motility would be expected to directly affect fertility, CASA may be a more robust endpoint for risk assessment in reproductive toxicology studies than flow cytometric analysis of membrane integrity.
authors.affiliation: Department of Safety Assessment, Merck Research Laboratories, West Point, Pennsylvania 19486, USA. vetter@merck.com
authors.forename: C M
authors.initials: CM
authors.lastname: Vetter
authors.forename: J E
authors.initials: JE
authors.lastname: Miller
authors.forename: L M
authors.initials: LM
authors.lastname: Crawford
authors.forename: M J
authors.initials: MJ
authors.lastname: Armstrong
authors.forename: J H
authors.initials: JH
authors.lastname: Clair
authors.forename: M W
authors.initials: MW
authors.lastname: Conner
authors.forename: L D
authors.initials: LD
authors.lastname: Wise
authors.forename: T R
authors.initials: TR
authors.lastname: Skopek
mesh_terms: D000085:Acetates / Q000633:toxicity; D000818:Animals; D002462:Cell Membrane / Q000187:drug effects / Q000502:physiology; D002470:Cell Survival; D003272:Contraceptive Agents, Male / Q000633:toxicity; D005434:Flow Cytometry / Q000379:methods; D007091:Image Processing, Computer-Assisted / Q000379:methods; D066298:In Vitro Techniques; D008297:Male; D051381:Rats; D013076:Sperm Count; D013078:Sperm Immobilizing Agents / Q000633:toxicity; D013081:Sperm Motility / Q000187:drug effects / Q000502:physiology*; D013094:Spermatozoa / Q000187:drug effects / Q000502:physiology*; D014649:Vas Deferens / Q000166:cytology / Q000187:drug effects; D000517:alpha-Chlorohydrin / Q000633:toxicity
chemical_list: D000085:Acetates; D003272:Contraceptive Agents, Male; D013078:Sperm Immobilizing Agents; C088674:dibromoacetic acid; D000517:alpha-Chlorohydrin