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 µg, least square mean ± SEM) was produced on the day of ovulation, whereas the lowest amount (1.25 ± 0.68 µg) 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.

Light and Scanning Electron Microscopic Studies of Oviductal Epithelium in Thai Swamp Buffalo (Bubalus bubalis) at the Follicular and Luteal Phases

“…The general histological changes in four different segments of buffalo oviducts during both the follicular and luteal phases in this study were similar to the previous observations in the bovine oviduct (Suarez et al. 1997; Bergqvist et al. 2005a,b).…”

“…2001). Recently, the presence of hyaluronan, syndecans and sulphated glycosaminoglycans in bovine oviductal epithelium and intraluminal fluid, especially in the sperm reservoir, has been studied by Bergqvist et al. (2005b) and Bergqvist and Rodriguez‐Martinez (2006) suggesting the specific activities of secretory cells in the UTJ and caudal isthmus to support the viability and fertilizing capacity of spermatozoa during their storage at pre‐ovulation period.…”

In vitrocapacitation of bull spermatozoa by oviductal fluid and its components

“…Others suggest that the sperm reservoir (the utero-tubal junction and adjacent part of isthmus) prevents capacitation, and that capacitation occurs during transport of the spermatozoa towards the ampullar isthmic junction (AIJ) when they are exposed to increased amounts of bicarbonate (Rodriguez-Martinez, 2001;Rodriguez-Martinez et al, 2001Tienthai et al, 2004). The reason for this absence of difference may be that the oviductal isthmic catheters were placed closer to the ampullar isthmic junction (AIJ) than to the sperm reservoir (Bergqvist et al, 2005). The present investigation showed no overall difference between ODF from the ampullar or isthmic regions in eliciting bull sperm capacitation.…”

Improving bovine semen diluents: insights from the male and female reproductive tracts, and the potential relevance of cervical mucins

“…However, it seems to be the least potent GAG at inducing the acrosome reaction. As HA is present in the oviductal fluid (Bergqvist et al, 2005), this could have some influence on sperm in vivo. Chondroitin sulphate B has been implicated in the capacitation of bovine sperm within the oviduct in vivo and its ability to induce the capacitation of bovine sperm in vitro has been confirmed (Thérien et al, 2005;.…”