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Annual Review of Physiology 1977
Review
Topics: Animals; Basement Membrane; Biological Transport; Blood Flow Velocity; Blood Pressure; Bone Marrow; Bradykinin; Capillaries; Endothelium; Humans; Methods; Microcirculation; Periodicity; Prostaglandins; Pulmonary Alveoli
PubMed: 322601
DOI: 10.1146/annurev.ph.39.030177.002135 -
The Orthopedic Clinics of North America Jan 1988Peripheral nerve trunks are well-vascularized structures where a well-developed collateral system may compensate for local vascular damage. Interference with intraneural... (Review)
Review
Peripheral nerve trunks are well-vascularized structures where a well-developed collateral system may compensate for local vascular damage. Interference with intraneural blood flow is reflected rapidly in disturbances in nerve function. In compression lesions and nerve entrapments, the microvascular factor plays an important pathophysiologic role for development of symptoms. Although endoneurial capillaries normally constitute a BNB helping to optimize endoneurial environment, damage to the vessels may induce a miniature closed compartment syndrome by increasing the permeability, thereby contributing to increased endoneurial fluid pressure and development of an intrafascicular edema. Surgeons, performing intraneural dissections, should be aware of the potential risks associated with intraneural bleedings, edema, and intraneural fibrosis.
Topics: Arteriovenous Anastomosis; Humans; Ischemia; Microcirculation; Nerve Compression Syndromes; Peripheral Nerve Injuries; Peripheral Nerves
PubMed: 3275919
DOI: No ID Found -
The Journal of Physiology Mar 2011The microcirculation exemplifies the mesoscale in physiological systems, bridging larger and smaller scale phenomena. Microcirculatory research represents an example of... (Review)
Review
The microcirculation exemplifies the mesoscale in physiological systems, bridging larger and smaller scale phenomena. Microcirculatory research represents an example of a 'middle-out,' rather than 'top-down' or 'bottom-up,' approach to the study of biological function. Computational and mathematical approaches can be used to analyse the functioning of the microcirculation and to establish quantitative relationships between microvascular processes and phenomena occurring on larger and smaller scales, leading to insights which could not be obtained solely by reductionist biological experiments. Given its integrative approach to processes occurring on disparate scales and its emphasis on theoretical as well as experimental approaches, microcirculatory research belongs within current definitions of systems biology.
Topics: Animals; Computer Simulation; Microcirculation; Models, Biological; Systems Biology
PubMed: 21242255
DOI: 10.1113/jphysiol.2010.201541 -
Physiological Reviews Jul 1990
Review
Topics: Animals; Humans; Kidney Medulla; Microcirculation
PubMed: 2194225
DOI: 10.1152/physrev.1990.70.3.885 -
Reviews in Endocrine & Metabolic... Mar 2013In most humans, obesity is associated with a chronic low-grade inflammatory reaction occurring in several organ tissues, including the adipose tissue. Infiltration of... (Review)
Review
In most humans, obesity is associated with a chronic low-grade inflammatory reaction occurring in several organ tissues, including the adipose tissue. Infiltration of bone marrow derived leukocytes (granulocytes, monocytes, lymphocytes) into expanding adipose depots appears to be an integral component of inflammation in obesity. Circulating leukocytes invade organ tissues mainly through post-capillary venules in the microcirculation. The endothelium of the post-capillary venules acts as a gatekeeper to leukocyte adhesion and extravasation by displacing on its luminal surface adhesion molecules that bind the adhesive receptors expressed on circulating leukocytes. Several studies investigating the impact of obesity on the microcirculation have demonstrated the occurrence of microvascular dysfunction in experimental animal model of obesity, as well as in obese humans. To date though, working hypotheses and study designs have favored the view that microvascular alterations are secondary to adipose tissue dysfunction. Indeed, a significant amount of data exists in the scientific literature to support the concept that microvascular dysfunction may precede and cause adipose tissue inflammation in obesity. Through review of key published data, this article prospectively presents the concept that in response to nutrients overload the vascular endothelium of the microcirculation acutely activates inflammatory pathways that initiate infiltration of leukocytes in visceral adipose tissue, well before weight gain and overt obesity. The anatomical and physiological heterogeneity of different microcirculations is also discussed toward the understanding of how obesity induces different inflammatory phenotypes in visceral and subcutaneous fat depots.
Topics: Adipose Tissue; Animals; Humans; Inflammation; Microcirculation; Selectins
PubMed: 23378133
DOI: 10.1007/s11154-013-9236-x -
Arquivos Brasileiros de Cardiologia Aug 2018
Topics: Cardiovascular Diseases; Humans; Microcirculation
PubMed: 30183978
DOI: 10.5935/abc.20180149 -
Annales de Cardiologie Et D'angeiologie May 1991
Review
Topics: Aged; Aging; Animals; Humans; Microcirculation; Middle Aged; Regional Blood Flow
PubMed: 1859131
DOI: No ID Found -
Pharmacology & Therapeutics Jun 2000Coronary microvessels play a pivotal role in determining the supply of oxygen and nutrients to the myocardium by regulating the coronary flow conductance and substance... (Review)
Review
Coronary microvessels play a pivotal role in determining the supply of oxygen and nutrients to the myocardium by regulating the coronary flow conductance and substance transport. Direct approaches analyzing the coronary microvessels have provided a large body of knowledge concerning the physiological and pharmacological characteristics of the coronary circulation, as has the rapid accumulation of biochemical findings about the substances that mediate vascular functions. Myogenic and flow-induced intrinsic vascular controls that determine basal tone have been observed in coronary microvessels in vitro. Coronary microvascular responses during metabolic stimulation, autoregulation, and reactive hyperemia have been analyzed in vivo, and are known to be largely mediated by metabolic factors, although the involvement of other factors should also be taken into account. The importance of ATP-sensitive K(+) channels in the metabolic control has been increasingly recognized. Furthermore, many neurohumoral mediators significantly affect coronary microvascular control in endothelium-dependent and -independent manners. The striking size-dependent heterogeneity of microvascular responses to all of these intrinsic, metabolic, and neurohumoral factors is orchestrated for optimal perfusion of the myocardium by synergistic and competitive interactions. The regulation of coronary microvascular permeability is another important factor for the nutrient supply and for edema formation. Analyses of collateral microvessels and subendocardial microvessels are important for understanding the pathophysiology of ischemic hearts and hypertrophied hearts. Studies of the microvascular responses to drugs and of the impairment of coronary microvessels in diseased conditions provide useful information for treating microvascular dysfunctions. In this article, the endogenous regulatory system and pharmacological responses of the coronary circulation are reviewed from the microvascular point of view.
Topics: Animals; Capillaries; Coronary Circulation; Humans; Microcirculation
PubMed: 10882810
DOI: 10.1016/s0163-7258(00)00057-7 -
American Journal of Otolaryngology 1988The delivery of nutrients to the tissues and the removal of waste products from the tissues is made possible by forcing a stream of blood through an arborizing network... (Review)
Review
The delivery of nutrients to the tissues and the removal of waste products from the tissues is made possible by forcing a stream of blood through an arborizing network of microscopic blood vessels that comprise the microcirculation. The rapidity of the flow stream and, therefore, the rate of nutrient delivery to the tissue, is regulated by the automatic adjustment of the caliber of the precapillary arterioles that serve as the primary loci of vascular resistance. Exchange between the blood stream and the parenchymal cells occurs in capillaries and pericytic venules. Pathologic processes such as inflammation, diabetes, ischemia, and hypertension are characterized by abnormalities in microvascular structure and function.
Topics: Animals; Capillary Permeability; Homeostasis; Humans; Microcirculation; Vascular Diseases
PubMed: 3067590
DOI: 10.1016/s0196-0709(88)80035-8 -
Journal of the Chinese Medical... Aug 2015From a hemodynamic point of view, hepatic vascular resistance and portal inflow determine the level of portal pressure. Factors that determine hepatic vascular... (Review)
Review
From a hemodynamic point of view, hepatic vascular resistance and portal inflow determine the level of portal pressure. Factors that determine hepatic vascular resistance include both structural and dynamic components. Among the structural components are histological characteristics such as steatosis, fibrosis, regeneration nodules, and neo-angiogenesis. Dynamic structures include cells with contractile properties such as hepatocytes, hepatic stellate cells, sinusoidal endothelial cells, and Kupffer cells. The contributions of the interactions between four cells in cirrhotic livers resulted in hepatic endothelial dysfunction, hepatic microcirculatory dysfunction, hepatic venous dysregulation, hepatic fibrogenesis, and subsequently increased intrahepatic resistance and portal hypertension in cirrhosis. The pathogenic mechanisms that trigger the associated abnormalities in hepatic microcirculations include persistent endotoxemia, increased hepatic oxidative stress, activated endocannabinoids substances, pathogenic sinusoidal remodeling, and hypoperfusion in cirrhotic livers. Cumulative data suggested that various therapeutic strategies targeting hepatic microcirculation provided effective improvement of the systemic abnormalities of cirrhosis. Accordingly, the mechanistic and therapeutic approaches focusing on the disarrangement of hepatic microcirculation will be introduced in this article.
Topics: Bacterial Translocation; Endocannabinoids; Fibroblast Growth Factor 2; Humans; Liver Circulation; Liver Cirrhosis; Microcirculation; Nitric Oxide; Vascular Endothelial Growth Factor A
PubMed: 26074366
DOI: 10.1016/j.jcma.2015.05.005