Review

Authors: C A Wagenvoort

Topics: Humans; Hypertension, Pulmonary; Infant; Muscle, Smooth, Vascular; Pulmonary Artery; Tunica Intima

PubMed: 7974326
DOI: 10.1136/thx.49.suppl.s39

Review

Authors: Christopher T Johnson, Luke P Brewster

Carotid artery intima-media thickness (IMT) is a biomarker for cardiovascular disease that also predicts the risk of cardiovascular mortality. Angiotensin-converting enzyme (ACE) inhibition is a unique therapeutic modality because it both treats hypertension and improves arterial health and cardiovascular disease outcomes. Controversy exists regarding the role of ACE inhibitors and angiotensin receptor blockers (ARBs) in IMT regression. Our article provides an update on how ACE inhibitors and ARBs could play a role in decreasing IMT.

Topics: Angiotensin Receptor Antagonists; Angiotensin-Converting Enzyme Inhibitors; Cardiovascular Diseases; Carotid Arteries; Humans; Renin-Angiotensin System; Risk Assessment; Tunica Intima

PubMed: 23680737
DOI: 10.3810/hp.2013.04.1026

Authors: Katsutoshi Miura

OBJECTIVES

Aging causes stiffness and decreased function of the renal artery (RA). Histological study with light microscopy can reveal microscopic structural remodeling but no functional changes. The present study aimed to clarify the association between structural and functional aging of the RA through the use of scanning acoustic microscopy.

METHODS

Formalin-fixed, paraffin-embedded cross-sections of renal arteries from 64 autopsy cases were examined. Speed-of-sound (SOS) values of three layers, which correspond to the stiffness, were compared among different age groups. SOS of the tunica media was examined in terms of blood pressure (BP) and SOS of the ascending aorta. Vulnerability to proteases was assessed by SOS reduction after collagenase treatment.

RESULTS

The tunica intima presented inward hypertrophy with luminal narrowing, and the tunica media showed outward hypertrophic remodeling with aging. SOS of the tunica media and internal and external elastic laminae showed a reverse correlation with age. SOS of the tunica media was negatively correlated with BP and strongly associated with that of the aorta. The tunica media of young RAs were more sensitive to collagenase compared with the old ones.

CONCLUSIONS

Scanning acoustic microscopy is useful for observing the aging process of the RA. This technique simultaneously shows structural and mechanical information from each portion of the RA. In the process of aging, the RA loses contractile function and elasticity as a result of protease digestion. The tunica media and the internal and external elastic laminae exhibit reduced stiffness, but the tunica intima stiffens with atherosclerosis. As a consequence, the RA's outer shape changes from round to oval with inward and outward hypertrophy. This indicates that the inner resistant intima supports the mechanical weakness of the tunica media to compensate for an increase in BP with aging.

Topics: Adult; Aged, 80 and over; Aging; Autopsy; Blood Pressure; Female; Humans; Male; Microscopy, Acoustic; Renal Artery; Tunica Intima; Tunica Media

PubMed: 33147291
DOI: 10.1371/journal.pone.0234759

Review

Authors: Luis A Martinez-Lemus

Arterioles are the blood vessels in the arterial side of the vascular tree that are located proximal to the capillaries and, in conjunction with the terminal arteries, provide the majority of resistance to blood flow. Consequently, arterioles are important contributors to the regulation of mean arterial pressure and tissue perfusion. Their wall consists of cellular and extracellular components that have been traditionally classified as conforming three layers: an intima containing endothelial cells sited on a basement membrane; a media made of an internal elastic lamina apposed by one or two layers of smooth muscle; and an adventitia composed mostly of collagen bundles, nerve endings and some fibroblasts. These components of the arteriolar wall are dynamically interconnected, providing a level of plasticity to the arteriolar wall that blurs the traditional boundaries of a rigid layered classification. This MiniReview focuses on the structural conformation of the arteriolar wall and shows how wall components interact spatially, functionally and temporally to control vascular diameter, regulate blood flow and maintain vascular permeability.

Topics: Animals; Arterioles; Capillary Permeability; Connective Tissue; Connective Tissue Cells; Humans; Tunica Intima; Tunica Media; Vascular Resistance

PubMed: 21989114
DOI: 10.1111/j.1742-7843.2011.00813.x

Review

Authors: Patricia Martinez-Quinones, Cameron G McCarthy, Stephanie W Watts...

Morphological and physiological changes in the vasculature have been described in the evolution and maintenance of hypertension. Hypertension-induced vascular dysfunction may present itself as a contributing, or consequential factor, to vascular remodeling caused by chronically elevated systemic arterial blood pressure. Changes in all vessel layers, from the endothelium to the perivascular adipose tissue (PVAT), have been described. This mini-review focuses on the current knowledge of the structure and function of the vessel layers, specifically muscular arteries: intima, media, adventitia, PVAT, and the cell types harbored within each vessel layer. The contributions of each cell type to vessel homeostasis and pathophysiological development of hypertension will be highlighted.

Topics: Adipose Tissue; Animals; Arterial Pressure; Arteries; Humans; Hypertension; Tunica Intima; Tunica Media; Vascular Remodeling

PubMed: 29788246
DOI: 10.1093/ajh/hpy083

Comparative Study

Authors: Rebecca C Thurston, Karen A Matthews

Racial and socioeconomic status (SES) disparities in cardiovascular disease (CVD) risk are well established among adults. However, little is known about disparities in CVD risk among adolescents, particularly considering indices of subclinical CVD. Our aim was to examine socioeconomic and racial disparities in subclinical CVD indices among adolescents. We hypothesized that African American and lower SES adolescents would show greater arterial stiffness and intima media thickness compared to Caucasian and higher SES adolescents, respectively. Participants were 81 African American and 78 Caucasian adolescents (mean age=17.8) from two schools in Pittsburgh, PA, USA. Measures of subclinical CVD were pulse wave velocity and intima media thickness, as assessed by Doppler and B-mode ultrasound, respectively. SES indices included parental education, family income, family assets, subjective social status, and census-derived neighborhood SES. Hypotheses were evaluated in multiple linear regression models with the covariates age, gender, body mass index, and systolic blood pressure. Results indicated that African American adolescents were more often in low SES positions than Caucasians. When considered individually, racial and SES disparities in pulse wave velocity, and to a lesser extent, intima media thickness, were evident. When race and SES were considered together, high school education, low or medium income, and low neighborhood SES were associated with higher pulse wave velocity. Fewer assets were associated with higher intima media thickness. In conclusion, racial and SES disparities in indices of subclinical CVD were observed, with findings most pronounced for SES disparities in pulse wave velocity. This study extends previous findings in adults to adolescents, indicating that disparities in arterial stiffness and intima media thickness occur as early as adolescence. Efforts to reduce socioeconomic and racial disparities in CVD should target disparities early in life.

Topics: Adolescent; Black or African American; Blood Flow Velocity; Cardiovascular Diseases; Carotid Arteries; Female; Femoral Artery; Follow-Up Studies; Health Status Disparities; Humans; Linear Models; Male; Pennsylvania; Social Class; Socioeconomic Factors; Tunica Intima; Ultrasonography; White People

PubMed: 19147264
DOI: 10.1016/j.socscimed.2008.12.029

Authors: Virginia J Hoglund, Xiu Rong Dong, Mark W Majesky...

Topics: Animals; Bone Marrow Cells; Connective Tissue; Mice; Models, Biological; Myocytes, Smooth Muscle; Neovascularization, Pathologic; Stem Cells; Tunica Intima; Vascular Diseases

PubMed: 20844267
DOI: 10.1161/ATVBAHA.110.211433

Review

Authors: Mingyi Wang, Robert E Monticone, Edward G Lakatta...

Arterial aging is a cornerstone of organismal aging. The central arterial wall structurally and functionally remodels under chronic proinflammatory stress over a lifetime. The low-grade proinflammation that accompanies advancing age causes arterial wall thickening and stiffening. These structural and functional alterations are consequences of adverse molecular and cellular events, e.g. an increase in local angiotensin II signaling that induces an inflammatory phenotypic shift of endothelial and smooth muscle cells. Thus, interventions to restrict proinflammatory signaling are a rational approach to delay or prevent age-associated adverse arterial remodeling.

Topics: Aging; Angiotensin II; Animals; Arteries; Atherosclerosis; Haplorhini; Humans; Hypertension; Myocytes, Smooth Muscle; Rabbits; Rats; Signal Transduction; Tunica Intima; Tunica Media; Vascular Remodeling

PubMed: 25171100
DOI: 10.1159/000362548

Review

Authors: M O Pentikäinen, K Oörni, M Ala-Korpela...

Atherosclerosis is characterized by chronic inflammation of an injured intima. The pathological processes are initiated by accumulation of morphologically distinct, modified forms of LDL, and followed by cellular infiltration and foam cell formation. Activated intimal cells secrete enzymes and agents capable of modifying LDL, and the modified lipids of LDL, in turn, are able to activate intimal cells and to trigger various inflammatory signals. These processes can initiate and maintain a vicious circle in the intima and lead to lesion progression. In this review, we focus on the LDL modifications relevant to the initial lipid accumulation and discuss their pro-inflammatory effects.

Topics: Arteriosclerosis; Cholesterol, LDL; Humans; Inflammation; Tunica Intima

PubMed: 10762453
DOI: 10.1046/j.1365-2796.2000.00655.x

Authors: Beatrice A Golomb

Topics: Aorta, Abdominal; Arteriosclerosis; Carotid Arteries; Carotid Artery Diseases; Humans; Metabolic Syndrome; Tunica Intima; Ultrasonography

PubMed: 19520252
DOI: 10.1016/j.jacc.2009.03.029