Temporal changes to uterine collagen types I, III and V in relation to early pregnancy in the rat

Abstract

Uterine tissues of pregnant rats were extracted to define any changes to the proportions of collagens types I, III and V. The total concentration of extracted collagen was determined in tissue samples from implant and adjacent non-implant (NI) sites. Extracts were also subjected to polyacrylamide gel electrophoresis (PAGE), immunoblotting and gel densitometry to define the collagen types and to determine their relative proportions. By relating the proportions to the collagen concentrations in the extracts, type I was found to be the predominant collagen in both tissue regions although the concentration in the implant sites was lower than that in the NI sites. The concentration of Type I collagen decreased significantly over the period of observation in both implant and NI sites. Although the concentrations of collagen type III and type V also decreased in the implant sites, they did not alter in the NI sites. The results demonstrate that shortly after the initiation of implantation the uterus responds to the presence of the implanting embryo by decreasing the concentration of all three types of collagen. This indicates that their metabolism may, in part, be regulated by similar mechanisms. Furthermore, it was evident that a decrease in the concentration of collagen type I was initiated in uterine areas that, at the time of sampling, were not directly involved with implantation. During the study, it was found that the alpha 1 chain of collagen type V separated into two distinct bands when run on gels containing 3.8 M urea.(ABSTRACT TRUNCATED AT 250 WORDS)

Immunohistochemical Assessment of Collagen Types I, III, IV and VI in Biopsy Samples of the Bovine Uterine Wall Collected during the Oestrous Cycle

“…This is in contrast to recent findings in the goat, where collagen type I is diffusely arranged throughout the uterine stroma and does not exhibit any differences in intensity or distri- bution of immunostaining [Guillomot, 1999]. The abovementioned subepithelial meshwork of this fibre type seems to be a species-specific feature, since it has not been reported from other species such as humans [Aplin et al, 1988;Stovall et al, 1992], rats [Hurst et al, 1994] and goat [Guillomot, 1999]. During pregnancy this thin web of collagen type I fibres increases to a thick subepithelial membrane which should increase the tensile strength of the uterine wall carrying the growing fetus [Stelljes et al, 1998].…”

Progesterone and Gravidity Differentially Regulate Expression of Extracellular Matrix Components in the Pregnant Rat Myometrium1

“…Type I collagen is the most common structural protein found in the body and is the most abundant collagen in the uterus. Type III collagen, which often colocalizes with type I collagen at a 1:5 ratio, is also widely distributed throughout the uterine muscle and is reported to be coregulated with collagen I [19,20]. It has also been reported that myometrial remodeling during pregnancy involves a controlled collagenolysis, evidenced by the disruption and partial degradation of collagen fibrils in late pregnancy [21,22].…”

Two-dimensional liquid chromatography with tandem mass spectrometry–based proteomic characterization of endometrial luminal epithelial surface proteins responsible for embryo implantation

“…Collagen a2 (VI) chain Expression levels of family members decreased in implantation sites (68). Collagen a1 (VI) chain Expression levels of family members decreased in implantation sites (68).…”