title: Hyaluronan and its binding proteins in the epithelium and intraluminal fluid of the bovine oviduct.
abstract: Hyaluronan (HA) is involved in several important steps of sperm storage and of fertilization. This study investigates the presence and concentration of HA in oviductal fluid (ODF), together with the localization of HA and the presence of hyaluronan-binding proteins (HABPs) in the oviductal epithelium of normally cycling dairy heifers and cows. The concentration and amount of HA in ODF, collected over the course of several oestrous cycles via catheters placed in the isthmic and ampullar tubal segments, were measured using an ELISA. The concentration and amount of HA in ODF did not vary significantly between these anatomical regions, nor between the stages of the oestrous cycle (p > 0.05), although the amount of HA seemed to peak during oestrous. The most HA per day (2.9 +/- 0.64 microg, least square mean +/- SEM) was produced on the day of ovulation, whereas the lowest amount (1.25 +/- 0.68 microg) was produced 4 days before ovulation. To investigate the localization of HA, tissue samples were retrieved at well-defined stages of the oestrous cycle and from corresponding regions of the oviduct. Sections and protein extracts from the tissue samples were studied histochemically using biotinylated HABP and immunoblotted with fluorescein isothiocyanate (FITC)-HA, respectively. Presence of HA labelling in the oviductal epithelium was restricted to the sperm reservoir, a localization that seemed to be cycle-independent. The immunoblotting of samples from the lining epithelium revealed seven bands of HABPs. We confirm that the bovine oviduct produces HA and its binding proteins, and that HA is mainly localized to the epithelium of the sperm reservoir.
authors.affiliation: Division of Comparative Reproduction, Obstetrics and Udder Health, Department of Clinical Sciences, Faculty of Veterinary Medicine and Animal Sciences, Swedish University of Agricultural Sciences and Uppsala University, Sweden. annsofi.bergqvist@kv.slu.se
authors.forename: Ann-Sofi
authors.initials: AS
authors.lastname: Bergqvist
authors.forename: Masaki
authors.initials: M
authors.lastname: Yokoo
authors.forename: Paraskevi
authors.initials: P
authors.lastname: Heldin
authors.forename: Jan
authors.initials: J
authors.lastname: Frendin
authors.forename: Eimei
authors.initials: E
authors.lastname: Sato
authors.forename: Heriberto
authors.initials: H
authors.lastname: Rodríguez-Martínez
mesh_terms: D000818:Animals; D002417:Cattle; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay; D004848:Epithelium / Q000378:metabolism; D005187:Fallopian Tubes / Q000737:chemistry / Q000378:metabolism*; D005260:Female; D018960:Hyaluronan Receptors / Q000378:metabolism*; D006820:Hyaluronic Acid / Q000032:analysis / Q000378:metabolism*
chemical_list: D018960:Hyaluronan Receptors; D006820:Hyaluronic Acid