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The epithelial layer of cells lining the heart and vessels of the circulatory system.



a tissue found in animals and man consisting of specialized cells that line the inner surfaces of blood and lymph vessels, as well as the cavities of the heart. The endothelium is formed from the mesenchyme. It consists of a single layer of closely packed flat cells, which are usually separated from underlying tissues by a basal membrane. The endothelium of lymph vessels has no basal membrane. The cytoplasm of endothelial cells of certain capillaries may have pores that account for the permeability of the capillary wall, as, for example, in the renal glomeruli.

The endothelium of the enlarged capillaries of the blood-forming organs and the endothelium present in the liver, adrenal cortex, and certain other organs has a great capacity for phagocytosis. The endothelial cells of these organs belong to the reticuloendothelial system.

References in periodicals archive ?
Vascular reactivity of the different fractions was assessed using porcine coronary artery rings either with or without endothelium, and in the presence or absence of specific pharmacological tools.
The normal endothelium shows a pattern of cells of similar size and shape with no abnormal dark or bright structures.
Damage to the vascular endothelium alters the formation and release of endothelial factors.
Although surgical techniques to replace the injured corneal endothelium have been developed, these procedures are technically difficult and challenging due to a shortage of donor corneas.
Conclusion: Testosterone induces endothelium and sex-dependent relaxation on sheep coronary artery in vitro.
However, advances over the past 30 years have revealed that the endothelium acts more like an organ that lines the whole of the circulatory system from the "heart to the smallest capillaries," and whose cells carry out many unique biological functions.
The authors of the study suggest that vitamin D3 may be of clinical importance in the restoration of dysfunctional cardiac endothelium after heart attack, capillary endothelium after brain ischemia (stroke), hypovolemia, vasculopathy, diabetes and atherosclerosis.
Differences in corneal thickness and corneal endothelium related to duration in Diabetes.
Due to the existence of interspecies variations in endothelial parameters, knowledge of normal data on the endothelium in each species is necessary.
6] M phenylephrine (see first set of experiments), aortic rings with intact endothelium were preincubated for 30 min with one (or two) of various compounds in order to explore the mechanisms involved in the vasorelaxant effect produced by clobenzorex.
Microvascular endothelium injury and dysfunction can cause tissue edema, ischemia, and hypoxia, finally resulting in organ function failure.

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