- Venule
- A little vein. Venules go from capillaries to veins, vessels that carry blood low in oxygen content from the body back to the heart. The deoxygenated form of hemoglobin (deoxyhemoglobin) makes the blood in veins and venules appear dark. Veins and venules are part of the afferent wing of the circulatory system which returns blood to the heart. .
* * *- high endothelial postcapillary venules venules in the lymph node s, tonsils, and Peyer patches that have a high-walled endothelium through which blood lymphocytes migrate from the blood into the lymphatic parenchyma.- inferior macular v. [TA] a small tributary of the central vein of the retina that drains the lower part of the macula. SYN: venula macularis inferior [TA].- inferior nasal retinal v. [TA] the small vein that passes from the inferior medial (nasal) part of the retina to join the central vein. SYN: venula nasalis retinae inferior [TA], inferior nasal v. of retina.- inferior temporal retinal v. [TA] the small vein that passes from the lower lateral (temporal) part of the retina to enter the central vein. SYN: venula temporalis retinae inferior [TA], inferior temporal v. of retina.- medial v. of retina [TA] the small vein that passes from the part of the retina between the macula and the optic disk to join the central vein. SYN: venula medialis retinae [TA].- pericytic venules SYN: postcapillary venules.- postcapillary venules the microvasculature immediately following the capillaries, ranging in size from 10 to 50 μm, and characterized by investment of pericytes; they are the site of extravasation of blood cells, are particularly sensitive to histamine, and are believed to be important in blood-interstitial fluid exchanges. SYN: pericytic venules.- stellate venules SYN: venulae stellatae, under venula.- superior macular v. [TA] a small tributary of the central vein of the retina that drains the upper part of the macula. SYN: venula macularis superior [TA].- superior nasal retinal v. [TA] the small vein that drains blood from the upper medial (nasal) part of the retina; it joins the central vein. SYN: venula nasalis retinae superior [TA], superior nasal v. of retina.- superior temporal retinal v. [TA] the v. that passes from the upper lateral (temporal) part of the retina to join the central vein. SYN: venula temporalis retinae superior [TA], superior temporal v. of retina.
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ve·nule 'vēn-(.)yü(ə)l, 'ven- n a small vein esp any of the minute veins connecting the capillaries with the larger systemic veins* * *
n.a minute vessel that drains blood from the capillaries. Many venules unite to form a vein.* * *
ven·ule (venґūl) venula; any of the small vessels that collect blood from the capillary plexuses and join to form veins. venular adj
Medical dictionary. 2011.