title: Effects of platelet-activating factor and platelet-activating factor: acetylhydrolase on in vitro post-thaw boar sperm parameters.
abstract: Cryopreservation of boar sperm compromises fertility after thawing by reducing sperm longevity and inducing acrosome reaction-like changes. In an attempt to improve the post-thaw motility and acrosome integrity of boar sperm, semen was frozen using a modified Westendorf method in which the medium was supplemented with either platelet-activating factor (PAF) or a recombinant platelet-activating factor:acetylhydrolase (PAF:AH; Pafase) before or after freezing. Platelet-activating factor is a phospholipid that is present in boar semen and PAF:AH is the naturally occurring enzyme that converts PAF to biologically inactive Lyso-PAF. Addition of PAF to the cryopreservation medium improved post-thaw motility immediately after thawing and after 3h incubation at 37 degrees C (60.0+/-0.0% and 25.0+/-2.9%; mean+/-S.E.M.) compared to the control sperm (41.7+/-1.7% and 10.0+/-2.9%; P<0.05). Acrosome integrity was higher immediately after thawing and after 3 and 6h incubation at 37 degrees C when sperm were frozen in the presence of Pafase (55.7+/-3.2%, 45.7+/-3.7% and 23.0+/-3.1%), compared to the control sperm (42.7+/-1.5%, 25.7+/-5.7% and 12.3+/-2.7%) and sperm frozen in the presence of PAF (33.0+/-3.7%, 26.3+/-2.2% and 11.7+/-0.3%; P<0.05). Addition of PAF to sperm after thawing improved motility immediately post-thaw (41.6+/-2.6%), compared with addition of Pafase (23.3+/-2.2%) or the control sperm with no supplementation of the medium (26.7+/-2.2%; P<0.05). However, this beneficial effect was lost by 3h post-thaw. Supplementation of boar semen cryopreservation medium with PAF and Pafase appeared to have beneficial effects on the in vitro quality of the sperm post-thaw.
authors.affiliation: Centre for Advanced Technologies in Animal Genetics and Reproduction (ReproGen), Faculty of Veterinary Science, The University of Sydney, NSW 2006, Australia. roslynb@vetsci.usyd.edu.au
authors.forename: R
authors.initials: R
authors.lastname: Bathgate
authors.forename: W M C
authors.initials: WM
authors.lastname: Maxwell
authors.forename: G
authors.initials: G
authors.lastname: Evans
mesh_terms: D043203:1-Alkyl-2-acetylglycerophosphocholine Esterase / Q000378:metabolism / Q000494:pharmacology*; D000818:Animals; D015925:Cryopreservation / Q000379:methods / Q000662:veterinary*; D008297:Male; D010972:Platelet Activating Factor / Q000378:metabolism / Q000494:pharmacology*; D012662:Semen Preservation / Q000379:methods / Q000662:veterinary*; D013081:Sperm Motility / Q000187:drug effects; D013094:Spermatozoa / Q000187:drug effects*; D013552:Swine / Q000502:physiology*; D013997:Time Factors
chemical_list: D010972:Platelet Activating Factor; D043203:1-Alkyl-2-acetylglycerophosphocholine Esterase