Disease relevance of Tunica Media

• In both hypertensive strains, mesenteric arterial media cross-sectional area was increased, with a significantly (P < .05) stronger degree of hypertrophy in renin TGR rats [1].
• The findings suggest that the responses of the arterial media to hypertension reflect appropriate adaptations to increased intramural tension with resultant medial thickening secondary to an increase in both cellular mass and extracellular matrix [2].
• Coronary perimicrovascular fibrosis, an increased coronary arterial wall to lumen ratio, increased immunoreactivity of PAI-1 in the tunica media and increased PAI-1 mRNA expression were present consistent with constrained mural proteo(fibrino)lysis [3].
• Subsequent organization of thrombotic material with hyperplasia of smooth muscle and inflammatory cells, luminal recovering with endothelial or pseudoendothelial cells, and atrophy of the tunica media led to incorporation of the prosthesis into the arterial wall [4].
• Cerebral amyloid angiopathy is a disorder in which deposition of amyloid within the arterial media and adventitia leads to intracerebral hemorrhage [5].

High impact information on Tunica Media

• Cyclosporine treatment prevents neointima formation and preserves the vascular media in aortic allografts [6].
• However, because most ET-1 is secreted abluminally, it might attain a higher concentration in the tunica media than in plasma [7].
• PreproET-1 and hECE-1 mRNA was also detected in VSMCs isolated from these vessels. irET-1 and irvWF staining in endothelium and tunica media was measured by use of microscope-coupled computer-assisted technology [7].
• When present, PR staining was observed in the cell nuclei of the tunica media and the subendothelial layer (neointima) [8].
• Intimal thickening was assessed as the degree of luminal narrowing (ratio of intimal area to the area on the luminal side of the arterial media) [9].

Chemical compound and disease context of Tunica Media

• These changes were characterized by vascular alterations consisting in hypertrophy of the tunica media accompanied by a decrease of luminal surface [10].
• Moreover, hypertrophy of the tunica media and the luminal surface were decreased and increased respectively in nicardipine-treated SHR [10].
• These data are consistent with a possible role for cyclic AMP in promoting changes in the tunica media that could lead to the development of vascular hypertrophy [11].
• In conclusion, treatment with enalapril and verapamil shows partial efficiency in preventing or treating aortic wall tunica media hypertrophy, suggesting that these alterations are due to a mechanism other than blood pressure control, where nitric oxide synthesis inhibition could be involved [12].
• Our results showed that both high-dose and low-dose perindopril may prevent hypertrophy of left ventricle and hypertrophy of the tunica media of superior mesenteric artery [13].

Biological context of Tunica Media

• However, the AT1 receptor antagonist had a more potent effect on the downregulation of the synthetic-type myosin heavy chains than the ACE inhibitor in spontaneously hypertensive rat aortic tunica media [14].
• We have reported that angiotensin II (Ang II) infusion to rats during the third and fourth weeks after vascular injury stimulates DNA replication in a larger proportion of smooth muscle cells (SMCs) in the arterial neointima than in the underlying media or the normal arterial media [15].
• Cell proliferation in the tunica media and enhanced synthesis of macromolecular components of the extracellular matrix were observed [16].
• During mouse embryonic development, the SM22beta gene is expressed in a temporally and spatially regulated pattern in the tunica media of arteries and veins, endocardium and compact layer of the myocardium, bronchial epithelium and mesenchyme of the lung, gastrointestinal epithelium and cartilaginous primordia [17].
• The IC50 values for ET-1 at the tunica media and regions of neovascularization were similar (mean +/- s.e.mean of n = 4 patients, 2.5 +/- 0.9 nM and 2.9 +/- 0.9 nM, respectively) whereas IC50 values for FR 139317 at regions of neovascularization (607 +/- 34 nM) were significantly higher than those of the tunica media (12.6 +/- 2.4 nM) (P < 0.0001) [18].

Anatomical context of Tunica Media

• In an uninjured rat carotid arteries, c-FLIP protein is abundant in the vascular media [19].
• Beta-aminopropionitrile (BAPN) alters the scleroproteins of the arterial media in a way which permits an increase in the stress (force/unit area) applied to smooth muscle cells at a given pressure [20].
• Moreover, Fe(2+) induced lysosomal accumulation of endogenous Abeta and APOE in cultured cells, and Abeta deposition in vascular tunica media in organotypic cultures of brain vessels [21].
• 4. These results indicate that ETA receptors are present on the tunica media of the diseased human coronary artery whereas a different ET receptor subtype exists at regions of neovascularization [18].
• In situ hybridization histochemistry indicates that the versican RNA transcript is located in the epithelium throughout the tunica media of the aorta [22].

Associations of Tunica Media with chemical compounds

• When compared with WKY, prehypertensive SHR also exhibited increased cross-sectional quantities of arterial media and elevated amplitudes of RVR change in response to norepinephrine and renal nerve stimulation [23].
• Thus, not only is the amount of EDRF released by acetylcholine reduced in the presence of atherosclerosis, the tunica media beneath the atheromatous plaque is also to some extent responsible for the superoxide-induced inactivation of EDRF [24].
• Within 24 hours of injury, Pluronic-based release of c-myc antisense oligomers reduced mRNA levels in the tunica media 2.5-fold and immunocytochemical identification of c-myc expression by 98.8% [25].
• Six of 32 fatty streaks (19%) contained cholesterol clefts, which were found in the musculo-elastic (deep) layer of the intima or in the tunica media [26].
• There was a significant positive correlation between hyaluronic acid content of normal tunica media and duration of diabetes, but not between hyaluronic acid content and age [27].

Gene context of Tunica Media

• RESULTS: In normal gastric tissues, CD34 positive fibroblastic cells were found just outside the vascular media, namely vascular adventitial fibroblastic cells [28].
• NPY-nerve fibres were found in tunica media and substance P- and GIP- nerve fibres in tunica adventitia [29].
• Morphological evidence is presented suggesting that ER synthesis is high in the tunica media when cell proliferation of smooth muscle cells is increased [30].
• Indirect immunofluorescence studies on frozen sections of aorta showed intense staining of the tunica media by antibodies to vimentin, whereas no reaction could be detected with antibodies to desmin [31].
• Immunohistochemistry of human carotid lesions showed high levels of GR in the tunica media, but large areas lacking GR in the fibrous lesion [32].

Analytical, diagnostic and therapeutic context of Tunica Media

• Immunohistochemical and Western blotting analysis showed reduced expression for up to 4 weeks of both the alpha8 and beta1 integrin subunits as well as smooth muscle alpha-actin in the tunica media following balloon injury [33].
• We used a well characterized cylindrical perfusion chamber to study the effect of ajoene on platelet deposition onto physiological substrates such as pig aortic subendothelium and tunica media as a model of mildly and severely damaged vessel wall respectively [34].
• RT-PCR demonstrated hHAS2 mRNA expression in the tunica media of large and small vessels [35].
• PURPOSE: Aortic dissection is characterized by fragility of the tunica media, and matrix metalloproteinases (MMPs) are enzymes that degrade the extracellular matrix of the aorta [36].

References