Year: 1989
Type: article
Abstract: A~TFIAOTThis study examined the lyric activity of bovine seminal plasma on zona-free oocytes commonly used to assess bovine capacitarion.Exposure of hamster oocytes (intact or zona-free) to undiluted seminal plasma resulted in lysis within 5 min.With intact oocytes, 1:5 to 1:20 seminal plasma resulted in swelling of the oocytes.With zona-free oocytes, seminal plasma (1:0 to 1:1000) resulted in lysis within 1 min to 3 h depending on dilution.Heating seminal plasma to inactivate complement did not reduce lyric activity, but boiling destroyed it.Lyric activity was present in seminal plasma from vasectomized bulls and in seminal vesicle fluid.After elution of seminal plasma through Sephadex G-200, lytic activity was only associated with the fraction conraining proteins of 200,000 to 45,000 dal.Lyric activity remained with washed capacitated bull sperm only when 107 sperm/ml or more were coincubated with zona-free oocytes at 37°C for 3 h.In conclusion, both bovine seminal plasma and capacitated sperm were lyric in the zona-free hamster oocyte assay.The results may explain why so few sperm are normally found at the site of fertilization.10, 13, 14), sperm (3, 8, 11) and oocytes (2, 9).Millar (13) demonstrated that the hemolytic factor was associated with infertility.Hunter et al. (4) found the hemolytic factor was a nondialyzable protein that was destroyed by heating to 100"C within 5 rain.It was synthesized in the seminal vesicles and ampullae of sexually mature bulls (4, 10, 11, 15).Kysilka (7) termed this factor a phospholipid-binding protein due to its ability to bind to cell membrane phospholipids.The hemolytic phospholipid-binding protein of bovine seminal plasma bound to the sperm acrosome and protoplasmic droplets during ejaculation (10, 11) and resulted in removal of protoplasmic droplets from the midpiece of the sperm.Masaki et al. ( 9) demonstrated that bovine seminal plasma possessed a factor that would lyse the v~.telline membrane of goat, rabbit, and bovine oocytes within 3 rain.Because the vitelline membranes of oocytes and red blood cells share chemical properties, especially in respect to phospholipids, they (9) hypothesized that the same factor caused both hemolysis and vitelline lysis.Their data (9) confirmed that both factors had identical properties.The objective of our study was to examine the lyric activity of bovine seminal plasma on zona-free hamster oocytes, which are commonly used to assess bovine sperm capacitarion (5).
Source: Journal of Dairy Science
Authors: A. Ijaz, A.G. Hunter, M. Ayoub
Institution: University of Minnesota
Language: English
Subfield: Reproductive Medicine
Field: Medicine
Domain: Health Sciences
Open Access status: bronze
OpenAlex ID: W2023620184