Glycosidase determination in bovine oviducal fluid at the follicular and luteal phases of the oestrous cycle.
Gamete recognition and binding of spermatozoa to the oviduct are carbohydrate-mediated processes in which several glycosidases are thought to have a role, although this has not been demonstrated unequivocally. Oviducal fluid is the biological milieu in which fertilisation and early embryo development take place, but the enzyme composition of oviducal fluid is largely unknown. The aim of the present study was to determine glycosidase activity and protein content in bovine oviducal fluid (bOF) and the volume of fluid collected per oviduct. Oviducts obtained from a slaughterhouse were classified as either in the follicular or luteal phase on the basis of ovarian luteal morphology. Oviducal fluid was aspirated, centrifuged and the volume determined. Samples were then frozen until assay. Substrates conjugated to 4-methylumbelliferyl were used to screen for the activity of seven glycosidases at pH 7.2. The results indicate that bOF has alpha-l-fucosidase, beta-N-acetyl-glucosaminidase, beta-d-galactosidase, alpha-D-mannosidase and beta-N-acetyl-galactosaminidase activity during both phases of the cycle, with the specific activity of the latter two enzymes being higher during the follicular phase. There was no N-acetyl-neuraminidase or alpha-d-galactosidase activity detected in bOF at either phase of the oestrous cycle at pH 7.2, but activity for both glycosidases was detected at pH 4.4. There were no differences in protein concentration or the volume of bOF collected between the two phases of the cycle. These findings indicate that oviducal fluid exhibits glycosidase activity, with specific variations throughout the oestrous cycle, suggesting that these enzymes play a role in carbohydrate-mediated events.
Carrasco
Luis Cesar
LC
Department of Physiology, University of Murcia, 30071 Murcia, Spain.
Coy
Pilar
P
Avilés
Manuel
M
Gadea
Joaquin
J
Romar
Raquel
R
D000118:Acetylglucosaminidase / Q000378:metabolism; D000818:Animals; D001826:Body Fluids / Q000201:enzymology; D002417:Cattle; D005260:Female; D005306:Fertilization / Q000502:physiology; D005498:Follicular Phase / Q000378:metabolism*; D005696:Galactosidases / Q000378:metabolism; D006026:Glycoside Hydrolases / Q000378:metabolism*; D008183:Luteal Phase / Q000378:metabolism*; D010057:Oviducts / Q000201:enzymology* / Q000502:physiology; D011247:Pregnancy; D005644:alpha-L-Fucosidase / Q000378:metabolism; D043323:alpha-Mannosidase / Q000378:metabolism; D048828:beta-N-Acetyl-Galactosaminidase / Q000378:metabolism
D005696:Galactosidases; D006026:Glycoside Hydrolases; D043323:alpha-Mannosidase; D005644:alpha-L-Fucosidase; D000118:Acetylglucosaminidase; D048828:beta-N-Acetyl-Galactosaminidase