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British Journal of Clinical Pharmacology May 1986
Topics: Half-Life; Hemodynamics; Humans; Kinetics; Liver; Liver Circulation; Verapamil
PubMed: 3718816
DOI: 10.1111/j.1365-2125.1986.tb02846.x -
Hepatology (Baltimore, Md.) Feb 2000
Review
Topics: Animals; Carbohydrate Metabolism; Gene Expression; Humans; Liver; Liver Circulation; Liver Diseases; Oxygen; Signal Transduction
PubMed: 10655244
DOI: 10.1002/hep.510310201 -
Gerontology 2002Numerous age-related changes in hepatic structure and function have been described, although liver function seems to be quite well maintained in old age. Few consistent... (Review)
Review
BACKGROUND/OBJECTIVE
Numerous age-related changes in hepatic structure and function have been described, although liver function seems to be quite well maintained in old age. Few consistent and reproducible observations and a lack of correlation between structural and functional data characterize the present state of our knowledge. In contrast to renal clearance, no equally reliable method exists to estimate hepatic drug clearance. The contribution of age to altered drug clearance in the elderly is difficult to assess as drug interactions, numbers and types of drugs taken at a time, underlying disease and increased interindividual variability are superimposed to the aging process.
METHODS
A comprehensive computer-assisted search of the literature.
RESULTS
A decline in liver volume and blood flow and a reduction in in vitro and in vivo metabolic capacity have been shown in older subjects, and the physiologic basis of reduced hepatic drug clearance in this age group.
CONCLUSIONS
After decades of research into the matter, the old and well-known aphorism "start lower--go slower" is valid more than ever in the field of geriatric prescribing. Not only renally excreted drugs but also substances which are metabolized and excreted by the liver should be used at a starting dose which is 30-40% smaller than the average dose used in middle-aged adults.
Topics: Aged; Aging; Humans; Liver; Liver Circulation; Pharmaceutical Preparations
PubMed: 11961363
DOI: 10.1159/000052829 -
The Korean Journal of Hepatology Dec 2010Portal hypertension (PHT) is associated with hemodynamic changes in intrahepatic, systemic, and portosystemic collateral circulation. Increased intrahepatic resistance... (Review)
Review
Portal hypertension (PHT) is associated with hemodynamic changes in intrahepatic, systemic, and portosystemic collateral circulation. Increased intrahepatic resistance and hyperdynamic circulatory alterations with expansion of collateral circulation play a central role in the pathogenesis of PHT. PHT is also characterized by changes in vascular structure, termed vascular remodeling, which is an adaptive response of the vessel wall that occurs in response to chronic changes in the environment such as shear stress. Angiogenesis, the formation of new blood vessels, also occurs with PHT related in particular to the expansion of portosystemic collateral circulation. The complementary processes of vasoreactivity, vascular remodeling, and angiogenesis represent important targets for the treatment of portal hypertension. Systemic and splanchnic vasodilatation can induce hyperdynamic circulation which is related with multi-organ failure such as hepatorenal syndrome and cirrhotic cadiomyopathy.
Topics: Collateral Circulation; Endothelial Cells; Hemodynamics; Hepatic Stellate Cells; Hypertension, Portal; Liver Circulation; Liver Cirrhosis; Splanchnic Circulation
PubMed: 21415576
DOI: 10.3350/kjhep.2010.16.4.347 -
Der Anaesthesist Nov 2004More than 50% of all patients on intensive care units acquire a systemic inflammation such as systemic inflammatory response syndrome (SIRS) or sepsis. The development... (Review)
Review
More than 50% of all patients on intensive care units acquire a systemic inflammation such as systemic inflammatory response syndrome (SIRS) or sepsis. The development of hepatic microcirculatory failure with consecutive organ damage might occur during the course of the systemic inflammation. The liver microcirculation is regulated by a complex network of cellular components and specific mediators. The perfusion in liver sinusoids is regulated by the tonus of the contractile Ito cells. Nitric oxide (NO) and carbon monoxide (CO) influence each other and cause the Ito cells to dilate while endothelin results in a contraction of the Ito cells. On-going studies are investigating the role of angiotensin II, catecholamines and prostaglandins for the regulation of the hepatic microcirculatory system during systemic inflammation. Some investigations aim to determine the impact of sedatives and analgesics on the hepatic microcirculation in sepsis and SIRS. Therefore, a decisive recommendation about the choice and dosage of sedatives and analgesics for these patients is not possible. Nevertheless, ketamine, midazolam and fentanyl with their potential anti-inflammatory properties seem to be suitable for patients with systemic inflammation.
Topics: Humans; Inflammation Mediators; Liver; Liver Circulation; Microcirculation; Systemic Inflammatory Response Syndrome
PubMed: 15502885
DOI: 10.1007/s00101-004-0770-5 -
Life Sciences Nov 2007Angiogenesis, the growth of new blood vessels, is essential during tissue repair. In contrast, uncontrolled angiogenesis promotes tumor. A balance between proangiogenic... (Review)
Review
Angiogenesis, the growth of new blood vessels, is essential during tissue repair. In contrast, uncontrolled angiogenesis promotes tumor. A balance between proangiogenic and antiangiogenic growth factors and cytokines tightly controls angiogenesis. With the identification of several proangiogenic molecules such as the vascular endothelial cell growth factor (VEGF), the fibroblast growth factors (FGFs), and the angiopoietins, and the recent description of specific inhibitors of angiogenesis such as platelet factor, angiostatin, endostatin, and vasostatin, it is recognized that therapeutic interference with vasculature formation offers a tool for clinical applications in various pathologies.
Topics: Animals; Blood Platelets; Humans; Immune System; Intercellular Signaling Peptides and Proteins; Liver Circulation; Neovascularization, Physiologic
PubMed: 17950364
DOI: 10.1016/j.lfs.2007.09.027 -
The American Journal of Physiology Feb 1966
Topics: Angiotensin II; Animals; Blood Pressure; Cattle; Hepatic Artery; Liver Circulation; Portal Vein; Tachyphylaxis
PubMed: 4285263
DOI: 10.1152/ajplegacy.1966.210.2.305 -
Gastroenterology May 2008
Review
Topics: Endothelium, Vascular; Humans; Hypertension, Portal; Liver Circulation; Vascular Resistance
PubMed: 18471549
DOI: 10.1053/j.gastro.2008.03.007 -
Liver Transplantation and Surgery :... Jul 1997
Review
Topics: Constriction; Hemodynamics; Humans; Liver Circulation; Liver Diseases; Liver Transplantation; Reperfusion
PubMed: 9346767
DOI: 10.1002/lt.500030411 -
Nauchnye Doklady Vysshei Shkoly.... 1990In acute experiments on dogs under nembutal anaesthesia the pressure and blood flow in the vessels supplying the liver have been recorded simultaneously with... (Comparative Study)
Comparative Study
In acute experiments on dogs under nembutal anaesthesia the pressure and blood flow in the vessels supplying the liver have been recorded simultaneously with registration of the hepatic blood content changes. Catecholamines injected into liver vessels have been found to change significantly the liver circulation: adrenaline and noradrenaline evoke the constriction of intrahepatic vessels and decrease the blood content in the liver, realising through the alpha-adrenoreceptors activation, isadrin causes a weak vasodilatation by the activation of beta-adrenoreceptors. A selective inactivation of isadrin in the liver is shown. The density of alpha-adrenoreceptors distribution in the intrahepatic vessels is large enough and apparently some times exceeds the density of beta-adrenoreceptors. In 1/3 of dogs the beta-adrenoreceptors in the liver vascular bed are absent at all or present in arterial bed only.
Topics: Animals; Blood Flow Velocity; Blood Pressure; Catecholamines; Dogs; Dose-Response Relationship, Drug; Female; Hemoglobins; Liver Circulation; Male
PubMed: 2275947
DOI: No ID Found