tunica adventitia

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Related to tunica adventitia: tunica intima, tunica media, Tunica serosa


 [too´nĭ-kah] (L.)
a tunic or coat; used in anatomic nomenclature to designate a membranous covering of an organ or a distinct layer of the wall of a hollow structure, as a blood vessel.
tunica adventi´tia the outer coat of various tubular structures.
tunica albugi´nea a dense white fibrous sheath that encloses a part or organ, such as the testicle or ovary.
tunica conjuncti´va the conjunctiva.
tunica dar´tos dartos.
tunica exter´na an outer coat, such as the fibroelastic coat of a blood vessel.
tunica inter´na an inner coat or layer.
tunica in´tima the innermost coat of a blood vessel; called also Bichat's tunic.
tunica me´dia the muscular middle coat of a blood vessel.
tunica muco´sa the mucous membrane lining of various tubular structures.
tunica muscula´ris the muscular coat or layer surrounding the tela submucosa in most portions of the digestive, respiratory, urinary, and genital tracts.
tunica pro´pria the proper coat or layer of a part, as distinguished from an investing membrane.
tunica sero´sa the membrane lining the external walls of the body cavities and reflected over the surfaces of protruding organs; it secretes a watery exudate.
tunica vagina´lis tes´tis the serous membrane covering the front and sides of the testis and epididymis.
tunica vasculo´sa a vascular coat, or a layer well supplied with blood vessels.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.


(ad-ven-tish'ă), [TA]
The outermost connective tissue covering of any organ, vessel, or other structure (or part thereof) not covered by a serous coat (visceral peritoneum); instead, the covering is properly derived from without (that is, from the surrounding connective tissue) and does not form an integral part of such organ or structure. Terminologia Anatomica lists adventitia (tunica adventitia) of the following organs: blood vessels, ductus deferens, esophagus, renal pelvis, seminal glands, and ureters.
Synonym(s): tunica adventitia [TA], membrana adventitia (1)
[L. adventicius, coming from abroad, foreign, fr. ad, to + venio, to come]
Farlex Partner Medical Dictionary © Farlex 2012


(ad'vĕn-tish'ă) [TA]
The outermost connective tissue covering of any organ, vessel, or other structure not covered by a serosa.
Synonym(s): tunica adventitia [TA] .
[L. adventicius, coming from abroad, foreign, fr. ad, to + venio, to come]
Medical Dictionary for the Health Professions and Nursing © Farlex 2012
References in periodicals archive ?
(2) The dissection of the coronary artery wall in ECM has been postulated to be due to the disruption of the vasa vasorum, which also explains the presence of hemorrhage between tunica adventitia and tunica media that displaces the inner artery wall toward the lumen.
Proximal left coronary artery featuring inflammatory infiltrate in the tunica adventitia and tunica media, with dissection of tunica media and resultant narrowing of the vessel lumen (hematoxylin-eosin, original magnification X200).
In 8 (8.3%) of the cases, thickening of the tunica adventitia was associated with only slight intimal thickening.
Observations of the current study reveal that marked thickening of tunica adventitia occurred in over 10% of the cases.
Conventionally, cells in the large arteries, whose wall are composed of three layers including tunica intima, tunica media and tunica adventitia, are mainly comprised of endothelial cells, smooth muscle cells (SMCs), fibroblasts (FBs), and macrophages.
Furthermore, TEM indicated the ubieties of TCs in tunica adventitia, intracellular communication between Tps, and vesicles shedding from TCs into the adjacent extracellular matrix.
The outer covering of the urethra is the tunica adventitia.
In all the slides, thickness of tunica intima was measured from luminal border upto internal elastic lamina; tunica media was measured between internal elastic lamina and external elastic lamina whereas thickness of tunica adventitia was measured from external elastic lamina up to its outermost boundary which could be easily identified.
The tunica adventitia was observed to consist of a meshwork of connective tissue.
Each lobule consisted of tunica mucosa comprising lamina epithelialis and lamina propria, tunica muscularis and tunica adventitia. All three layers were similar to the description in different domestic animals (Trautmann & Fiebiebiger, 1957; Dellmann & Wrobel, 1976; Sudhakar et al.).
The tunica adventitia was comprised of loosely arranged meshwork of collagen, reticulin and elastin fibers as reported in goats (Gupta, 1978) and buffalo (Sudhakar et al).
The MCA is a muscular artery and muscular arteries generally have the same basic composition as elastic arteries but the elastic tissue is reduced to a well-defined, fenestrated elastic sheet, the internal elastic lamina, in the tunica intima, and a diffuse external elastic lamina in the tunica adventitia. The tunica media is mainly composed of a thick layer of smooth muscle.