Rat Amnion Type IV Collagen Composition and Metabolism: Implications for Membrane Breakdown(2)

1 May

Type IV collagen is primarily localized to basement membranes. In the fetal membranes, type IV collagen is found in the basal lamina beneath the amniotic epithelial cells. It is also interspersed among trophoblast cells in the human chorion. Type IV collagen protomers are composed of three alpha chains joined in a triple helix. Six different alpha chains, each derived from a distinct gene, have been identified. There is marked tissue specificity of the type IV collagen chain repertoire, which appears to reflect functional roles of specific basement membranes. Beyond serving a structural role, type IV collagen is believed to influence cellular function. Notably, degradation of type IV collagen in the basement membrane causes loss of cell attachment (anoikis) and apoptosis of epithelial cells. buy ventolin inhalers

We carried out studies to characterize the type IV collagen composition and content of the rat amnion near the end of pregnancy and correlated changes in type IV collagen levels with expression of enzymes that degrade it. The hypothesis that induction of enzymes that degrade type IV collagen promotes amnion cell detachment, and apopto-sis was tested using an in vitro model.