Endothelium monolayer

After permeation through the corneal epithelium, molecules should then permeate through the hydrophilic corneal stroma and the corneal endothelium before reaching the aqueous humor. Thus, while the corneal epithelium favors the penetration of lipophilic compounds, the hydrophilic stroma favors the permeation of hydrophilic compounds. The corneal endothelium monolayer is not sealed by paracellular zonulae occludentes. Consequently this layer has only a minimal effect on the overall permeability of the cornea. Overall, the cornea as a whole is tailored to allow the permeation of moderately lipophilic compounds (close to log P = 2) [40], On the contrary, the reported optimal lipophilicity for compounds penetrating through an isolated epithelial layer of the cornea was around log P=4 [41],... 

F, Ante he and M, J. Poznan sky. The endothelium monolayer barrier to enzyme and drag delivery. Pharmaceutical Enzymes Marcel Dekker, New M, 1997 2 19-35. 

The Endothelium Monolayer Barrier to Enzyme and Drug Delivery... 

The mechanism of action and the injury potential of lipid mediators are still a matter of debate (Figure 4.3). Malik and co-workers recently reviewed the role of cellular and humoral mediators in pulmonary oedema and concluded that few humoral factors act independently to increase capillary permeability and that these mediators might cause pulmonary venoconstriction and raise pulmonary capillary hydrostatic pressure. This concept is in agreement with results of Shasby et al which demonstrated that leukotriene C4 applied directly to an endothelium monolayer did not accelerate albumin transfer across the monolayer. However, because the culture medium was rich in serum proteins (which avidly bind leukotrienes ), one cannot rule out a direct damaging effect to endothelial cells given access of the molecule to the endothelial cell. 

The innermost layer of an artery, which consists of loose connective tissue covered by a monolayer of endothelium that resides on a basement membrane. In human arteries, the intima often contains resident smooth muscle cells even early in life. Atherosclerotic plaques form in the intima. 

Offiier FA, Wirtz HC, Schiefer J et al (1992) Interaction of human malignant melanoma (ST-ML-12) tumor spheroids with endothelial cell monolayers. Damage to endothelium by oxygen-derived firee radicals. Am J Pathol 141 601-610... 

The inner surface of vessel is composed by a monolayer of adjacent endothelial cells. This layer is called endothelium and the underlying tissue is called subendothelium. 

The inner layer of the corneal stroma is a dense membrane of collagen like the basal membrane of the monolayer of corneal endothelium. Descemets membrane is transparent with a thickness varying from 7 to 20 pm, according to the age of the individual. Conjunctiva and cornea host nerve endings of high density in the snperhcial and basal layers. The cornea at the limbns smoothly changes to sclera with interconnected nontransparent collagen hbrils. 

PMN binding to and migration across endothelium initiates a sequence of events that resembles that following histamine treatment [14,30], namely, an increase in the permeability of the EC monolayer. For anionic plasma macro-molecules, theplasmalemmal vesicles and bansendothdial channels are suitable candidates for exit from the vessel lumen. Indeed, receptor-mediated tranacytosis of insulin and transferrin has been identified for brain capillaries [31—33], The insulin curriers have nut yet been idoitified, but it is speculated that they could be coaled vesicles and/or plasmalemmal vesicles. Transferrin [341 as well as ceruloplasmin [33,36] binding has been localized to coated pits and vesicles in the endothelium of bone marrow and liver capillary endothelium, respectively. 

Cerebrovascular pathologies are abundant in Alzheimer s disease (AD) and are demonstrated by changes in the endothelium, amyloid depositions in the cerebral blood vessels, and disruption of the BBB. A possible mechanism that underlies this phenomenon may be drawn from in vitro studies using a BBB model of a monolayer of vascular endothelial cells. Amyloid (3-peptide, which deposits in plaques of AD patients, induced in these cells permeability to albumin and apoptotic cell death." The potential clinical relevance of this finding was emphasized by intracarotid infusion of amyloid (3-peptide, which resulted in BBB damage. ... 

Capillaries in the Kidney. Filtration in the kidney occurs across a specialized capillary in the glomerulus. The glomerular capillary has several layers a monolayer of endothelial cells that interface with the flowing blood, an acellular basement membrane, and a filtration layer formed by glomerular epithelial cells. The endothelium is fenestrated that is, there are numerous... 

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