Lipopolysaccharide (LPS), produced by gram-negative bacteria, mediates vasodilatation, changing the action of contractile smooth muscle by increasing expression of nitric oxide synthase and prostaglandin. For the first time we demonstrate, by immunohistochemical methods, that administration of LPS to pregnant mice causes α-actin-mediated down-regulation of contractile filaments in uterine blood vessels, thereby potentially increasing vessels permeability, blood supply, and immune cells homing to this environment, culminating in the reestablishment of uterine homeostasis., B. Zavan ... [et al.]., and Obsahuje seznam literatury
One of the most abundant immunologic cell types in early decidua is the uterine natural killer (UNK) cell that despite the presence of cytoplasmic granules rich in perforin and granzymes does not degranulate in normal pregnancy. UNK cells are important producers of angiogenic factors that permit normal dilation of uterine arteries to provide increased blood flow for the growing feto-placental unit. Gram-negative bacteria lipopolysaccharide (LPS) administration can trigger an imbalance of pro-inflammatory and anti-inflammatory cytokines impairing the normal immune cells activity as well as uterine homeostasis. The present study aimed to evaluate by immunohistochemistry the reactivity of perforin and α-actin on UNK cell from LPStreated pregnant mice. For the first time, we demonstrate that LPS injection in pregnant mice causes α-actin down regulation, concomitantly with perforin loss in UNK cells. This suggests that LPS alters UNK cell migration and activates cytotoxic granule release., B. Zavan, A. M. do Amarante-Paffaro, V. A. Paffaro Jr., and Obsahuje bibliografii