Sinus endothelial cells

The conduit system and sinuses are lined by sinus endothelial cells (SECs). SECs are flattened cells that do not form a continuous layer, especially in the wall of the medullary sinus, but contain intercellular gaps or pores. Gaps have also been demonsriated in the floor of the subcapsular sinus. FRCs and SECs might be ontogenically related and serve to filriate lymph fluid collected from all peripheral tissues, including brain interstitial tissue and cerebrospinal fluid. 

The hematopoietic bone marrow is located primarily in the central portion of the pelvis, ribs, vertebrae, skuU, and femoral and humeral epiphyses. The anatomic structure of the bone marrow is characterized by the central venous marrow sinus, which is linked by coarse vascular sinusoids that intertwine a reticulin mesh where the cells are suspended. Thus hematopoiesis occurs in the extravascu-lar marrow spaces, which also contain endothelial cells, fibroblasts, macrophages, and adipocytes, collectively termed bone marrow stroma. Stromal cells are thought to be important hematopoietic components, providing growth factors, collagen, and cell adhesion proteins.When these cells are combined with accessory cells (lym-phocytes/monocytes) and cytokines, the mixture is referred to as the hematopoietic microenvironment. 

There is little information on prostaglandin formation by human cardiac tissue, most of which, based on measurements of thromboxane B2, prostaglandin E2 and 6-keto-prostaglandin in aortic and coronary sinus blood, is likely to be highly artifactual. In a recent experiment, Nowak and coworkers infused radiolabelled arachidonic acid into the coronary arteries of male volunteers 3 days following a single dose of aspirin, 600 mg, by which time cyclo-oxygenase activity in endothelial cells, but not in platelets, would... 

The receptor for HA endocytosis had been found on the membrane of endothelial cells of the liver sinuses and fundamentally differs from other hyaluronan-binding proteins (see [13] and references therein). 

It has been determined that some cells begin to aggregate after addition of hyaluronan. The observation of aggregation was the first indication that the polysaccharide macromolecule can be bound with the cell surface. At the present time, several protein receptors, which specifically bind biopolymers on the surface of the cytoplasmic membrane, have been isolated. These have a high affinity to the HA receptors CD44 and the receptor for HA-mediated motility (RHAMM) [123]. Another receptor for hyaluronan endocytosis was found on the membrane of the endothelial cells of the liver sinus. It differs significantly from other... 

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