The distribution of type IV collagen .ALPHA. chains in the mouse ovary and its correlation with follicular development

Abstract

The present study aims to identify alpha chains of type IV collagen in the basement membrane of the mouse ovarian follicle and examine their changes during follicular development using immunofluorescence microscopy with specific monoclonal antibodies. The basement membrane of the serous mesothelium enveloping the ovary contained all alpha chains of type IV collagen, alpha1(IV) through alpha6(IV) chains. Primordial follicles showed a distinct immunoreactivity against all six alpha chains in their basement membranes. Immunolabeling for alpha3(IV) and alpha4(IV) chains was almost eliminated in the primary follicles. In basement membranes of secondary and Graafian follicles, the immunofluorescent reaction of alpha3(IV) and alpha4(IV) chains disappeared in Graafian follicles, a partial reduction in fluorescent immunostaining intensity to alpha5(IV) and alpha6(IV) chains was observed; only alpha1(IV) and alpha2(IV) chains were not degraded throughout follicular development. On atretic follicles, in addition to alpha1(IV) and alpha2(IV) chains, alpha3(IV), alpha4(IV), alpha5(IV) and alpha6(IV) chains frequently persisted. A basement membrane-like matrix within the follicular granulosa cell layer, such as the focimatrix (focal intraepithelial matrix) and/or Call-Exner body, was also recognized in mouse secondary and Graafian follicles and contained alpha1(IV), alpha2(IV), alpha5(IV) and alpha6(IV) chains but not alpha3(IV) and alpha4(IV) chains. We expect that the decrease in alpha(IV) chains prompts follicular development and is a prerequisite condition for follicular maturation.

Defective Gonadotropin-Dependent Ovarian Folliculogenesis and Granulosa Cell Gene Expression in Inhibin-Deficient Mice

“…increases in Col1a2, Col4a4, Col3a1, and Col6a1 and decreases in Col4a6 and Col4a5) in preovulatory Inha Ϫ/Ϫ granulosa cells. It has been reported that collagen type IV chains-␣3 to -␣6 in the basal lamina decline during follicle growth (57,58), and in Inha Ϫ/Ϫ , these appear to be overexpressed compared with WT. How changes in collagen composition affect the phenotype of Inha Ϫ/Ϫ or contribute to alterations in Inha Ϫ/Ϫ gene expression is currently unknown.…”

Follicle-stimulating hormone regulation of microRNA expression on progesterone production in cultured rat granulosa cells

“…Previous study demonstrated that signaling through adhesion molecules such as collagen increased FSH receptor expression and progesterone production in granulosa cells from immature porcine ovarian follicles [34]. Nakano et al reported that the granulosa cell layer of the mouse ovarian follicle has a basement membrane like matrix containing Col4A1, Col4A2, Col4A5, Col4A6, and the expression of type IV collagen shows the decreasing trend in mouse follicular development [35]. Here we found that the expression pattern of Col4A1 was consistent with mir-29a expression with FSH treatment broadly.…”

Permselectivity of blood follicle barriers in mouse ovaries of the mifepristone-induced polycystic ovary model revealed by in vivo cryotechnique

“…5, some collagen type IV a-chains were immunohistochemically examined to reveal any changes in the major components of the basement membranes (Rodgers et al 1998, Nakano et al 2007). However, no apparent differences in the collagen a-chains were observed in the antral follicles between the PCO model and control mice (Fig.…”