Abstract:
:Intrinsic regulation of hepatic blood flow is mediated only through the hepatic artery because the liver is not able to directly regulate portal vein blood flow. Hepatic metabolic activity does not affect hepatic artery flow. Although the hepatic artery is affected by sympathetic nerves and blood-borne agents, the intrinsic regulation of the hepatic artery can be demonstrated if these factors are controlled. The primary intrinsic regulator of the hepatic artery is the hepatic arterial buffer response, which is the inverse response of the hepatic artery to changes in portal vein flow. The hepatic arterial buffer response is sufficiently powerful that doubling portal vein flow leads to maximal constriction in the hepatic artery, while low portal vein flow can result in maximal dilation. The mechanism of the hepatic arterial buffer response is based on adenosine washout, whereby adenosine is produced at a constant rate, independent of oxygen supply or demand, and secreted into a small fluid compartment that surrounds the hepatic arterial resistance vessels. If portal vein flow decreases, less adenosine is washed away into the portal blood and the accumulated adenosine leads to hepatic arterial dilation. Similarly, hepatic arterial autoregulation operates by the same mechanism, whereby a decrease in arterial pressure leads to a decrease in hepatic arterial flow, thus resulting in less adenosine washout into the hepatic artery blood. The accumulated adenosine leads to hepatic artery dilation. These intrinsic regulatory mechanisms tend to maintain total hepatic blood flow at a constant level, thus stabilizing hepatic clearance of hormones, venous return, and cardiac output.
journal_name
Can J Physiol Pharmacoljournal_title
Canadian journal of physiology and pharmacologyauthors
Lautt WWsubject
Has Abstractpub_date
1996-03-01 00:00:00pages
223-33issue
3eissn
0008-4212issn
1205-7541journal_volume
74pub_type
abstract::An account is given of the current state of knowledge of the contributions of the cerebellum and the forelimb motor cortex (MC) to the neural control of walking movements in the cat. The main emphasis is on information obtained by recording from single MC and cerebellar neurones in chronically instrumented cats engage...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章,评审
doi:
更新日期:1996-04-01 00:00:00
abstract::There have been conflicting observations regarding the effects of ketoconazole on hepatic metabolism. The objectives of these studies were to determine whether ketoconazole was an enzyme inducer or inhibitor in the mouse and then to establish the time frame of these ketoconazole-induced enzyme changes. Ketoconazole wa...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y90-170
更新日期:1990-08-01 00:00:00
abstract::To determine if increased endometrial vascular permeability (a response which precedes decidualization) could be obtained in temporally nonsensitized uteri by treatments designed to increase endometrial adenosine 3':5'-cyclic monophosphate (cAMP) concentrations, cholera toxin (an activator of adenylate cyclase) was in...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y85-172
更新日期:1985-09-01 00:00:00
abstract::The leaves and bark of Cassia glauca Lam., a glabrous tree in the family Fabaceae, are used in folk medicine for the treatment of diabetes. The aim of this study was to investigate the antidiabetic activity of the aqueous extract of C. glauca bark. The various parameters that were studied in treated or untreated normo...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/Y09-121
更新日期:2010-02-01 00:00:00
abstract::In both isolated canine ventricular trabecular muscle and Purkinje strand preparations, dl-sotalol and its two optical isomers d- and l-sotalol produced a concentration-dependent increase in action potential duration while other transmembrane electrical characteristics were not significantly affected. The magnitude of...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y85-248
更新日期:1985-12-01 00:00:00
abstract::Our studies are guided by the novel hypothesis that protein tyrosine phosphorylation is an important mechanism for regulating contraction of smooth muscle. Several lines of evidence are reviewed which suggest that enhanced tyrosine phosphorylation participates in mechanisms that regulate cytosolic Ca2+ and Ca2+ sensit...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章,评审
doi:10.1139/y94-207
更新日期:1994-11-01 00:00:00
abstract::The change in plasma and blood cell pools of L-glutamine during a single pass through the kidney was studied in dogs and rats. It was shown that the glutamine content of blood cells does not change following one passage through the renal vascular bed in normal or acidotic dogs. Furthermore, an infusion of L-glutamine ...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y85-145
更新日期:1985-07-01 00:00:00
abstract::Barbital-sedated, warm-acclimated (WA) or cold-acclimated (CA) rats were infused intravenously with noradrenaline (NA) at doses that elicited graded calorigenic responses. Blood flow (Q) to the various bodies of brown adipose tissue (BAT), the major sites of the NA-induced calorigenesis, was measured with labeled micr...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y80-140
更新日期:1980-08-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:
更新日期:1997-04-01 00:00:00
abstract::The effects of modafinil on heat thermoregulatory responses were studied in 10 male subjects submitted to a sweating test after taking 200 mg of modafinil or placebo. Sweating tests were performed in a hot climatic chamber (45 degrees C, relative humidity <15%, wind speed = 0.8 m x s(-1), duration 1.5 h). Body tempera...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 临床试验,杂志文章
doi:10.1139/y02-092
更新日期:2002-08-01 00:00:00
abstract::Epigallocatechin-3-gallate (EGCG), a polyphenol in green tea, is an effective antioxidant and possesses neuroprotective effects. Brain-derived neurotrophic factor (BDNF) and cyclic AMP response element-binding protein (CREB) are crucial for neurogenesis and synaptic plasticity. In this study, we aimed to assess the pr...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-2016-0333
更新日期:2017-12-01 00:00:00
abstract::Nonalcoholic fatty liver disease (NAFLD) is a spectrum of chronic liver conditions that are characterized by steatosis, inflammation, fibrosis, and liver injury. The global prevalence of NAFLD is rapidly increasing in proportion to the rising incidence of obesity and type 2 diabetes. Because NAFLD is a multifaceted di...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章,评审
doi:10.1139/cjpp-2016-0681
更新日期:2017-10-01 00:00:00
abstract::We investigated whether cell-to-cell coupling between myometrial cells of parturient rats is influenced by intracellular adenosine 3',5'-cyclic monophosphate (cAMP) concentration. To evaluate the coupling, we measured input resistance (Ro) and injected Lucifer Yellow (LY) using microelectrode techniques. The intercell...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y92-045
更新日期:1992-03-01 00:00:00
abstract::In open-chest pentothal-chloralose anesthetized dogs, plasma catecholamine and cyclic AMP levels were evaluated in the aortic and coronary sinus blood, during stimulations of the left ansa subclavia (1, 2, and 4 Hz). Basal aortic and coronary sinus catecholamine levels were respectively 0.373 +/- 0.090 and 0.259 +/- 0...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y81-080
更新日期:1981-06-01 00:00:00
abstract::The expression of tissue factor (TF) in tumors reportedly exacerbates the aggressiveness of several types of cancers. The shedding of TF-containing membrane particles is believed to influence the ability of tumors to expand and metastasize, and these microparticles may also be harmful in the onset of disseminated intr...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y09-063
更新日期:2009-09-01 00:00:00
abstract::Idiopathic pulmonary arterial hypertension (IPAH) is a rare and devastating condition. There is no known cure for IPAH, and current treatment options are not always effective. Autologous myeloid angiogenic cells (MACs) have been explored as a novel therapy for IPAH, but preliminary data from clinical trials show limit...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-2018-0424
更新日期:2019-04-01 00:00:00
abstract::Transmural nerve stimulation following sympathetic (guanethidine 10(-4) mol/L, phenoxybenzamine 2 X 10(-5) mol/L, propanolol 2 X 10(-6) mol/L) and muscarinic blockade (atropine 5 X 10(-5) mol/L) produces a relaxatory response in canine saphenous veins contracted with prostaglandin F2 alpha. This relaxatory response wa...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y86-225
更新日期:1986-10-01 00:00:00
abstract::The effect of diabetes (streptozotocin, 65 mg/kg ip), dietary protein intake (15-60%), and plasma amino acid concentrations on brain large neutral amino acid levels in rats was examined. After 20 days, the plasma concentrations of methionine and the branched chain amino acids (BCAA), valine, isoleucine, and leucine we...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y85-084
更新日期:1985-05-01 00:00:00
abstract::Nitric oxide (NO) production occurs through oxidation of the amino acid L-arginine by NO synthase (NOS). NO inhibits platelet activation by increasing the levels of cyclic guanosine monophosphate (cGMP), thus maintaining vascular homeostasis. Our group previously demonstrated (da Silva et al. 2005) an enhancement of t...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y10-111
更新日期:2011-02-01 00:00:00
abstract::Spironolactone is a diuretic steroid which is capable of blocking the binding of aldosterone to its cytosol receptor at the distal convoluted tubule. In addition, it has been shown that spironolactone is a strong inhibitor of steroidogenesis. More recently, new aldosterone antagonists have been discovered. Some of the...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:
更新日期:1983-01-01 00:00:00
abstract::The aim of this study was to determine if there was a synergistic or additive effect of a thiazolidinedione derivative (rosiglitazone (ROS)) and a vanadium compound (bis(ethylmaltolato)oxovanadium(IV) (BEOV)) on plasma glucose and insulin levels following chronic oral administration to Zucker diabetic fatty (ZDF) rats...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y03-094
更新日期:2003-11-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章,评审
doi:10.1139/y92-001
更新日期:1992-01-01 00:00:00
abstract::Molecular mechanisms by which exercise exerts cardiovascular benefits are poorly understood. Exercise-induced increase of endothelial NO synthase (eNOS) phosphorylation through the protein kinase Akt has been shown to be a key mechanism underlying the beneficial effect of exercise in coronary artery disease patients. ...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y10-107
更新日期:2011-01-01 00:00:00
abstract::Trimetazidine (TMZ) exhibits metabolic and cardioprotective effects. The aim of this study was to assess the effects of TMZ on interleukin-2 (IL-2) and interleukin-8 (IL-8) serum concentrations in 156 patients with stable coronary artery disease. They underwent a treadmill exercise test (TET) before and after 3 months...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 临床试验,杂志文章
doi:10.1139/cjpp-2016-0424
更新日期:2017-06-01 00:00:00
abstract::In older Aplysia, the central nervous system (CNS) (abdominal ganglion) exerts suppressive and facilitatory control over the peripheral nervous system (PNS) which initially mediates the gill withdrawal reflex and its subsequent habituation evoked by tactile stimulation of the siphon. In young animals, both the suppres...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y79-148
更新日期:1979-09-01 00:00:00
abstract::To determine whether the renal responses to atrial natriuretic factor (ANF) are altered in the diabetic state, the diuretic and natriuretic responses to ANF (0.25 microgram.kg-1.min-1, i.v.) were measured in streptozotocin (STZ) induced diabetic (DIA) rats. Urine flow and sodium excretion were measured before and afte...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y90-060
更新日期:1990-03-01 00:00:00
abstract::The endothelin receptors in rabbit isolated rings of saphenous artery and saphenous vein have been characterized using endothelin-1, endothelin-2, endothelin-3, sarafotoxin S6c, and BQ123. Although artery rings were more sensitive than those from vein to the contractile action of phenylephrine, endothelin-1 was about ...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y93-122
更新日期:1993-10-01 00:00:00
abstract::The metabolism of endogenous and exogenous diacylglycerol (DG) was studied in SM-3 cells derived from rabbit aortic smooth muscle to determine the biochemical step(s) responsible for degrading DG second messengers. Incubation of growth-arrested SM-3 cells with [3H]myristate for 2 h resulted in selective labelling of c...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:
更新日期:1997-10-01 00:00:00
abstract::The purpose of this article is to review the current state of knowledge of ethanol neurobehavioural teratogenesis and its postulated mechanisms. The review comprises an examination of ethanol teratogenesis in the human, including the fetal alcohol syndrome, and in experimental animals. Several current proposed mechani...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章,评审
doi:10.1139/y95-173
更新日期:1995-09-01 00:00:00
abstract::Lingonberry grown in northern Manitoba, Canada, contains exceptionally high levels of anthocyanins and other polyphenols. Previous studies from our lab have shown that lingonberry anthocyanins can protect H9c2 cells from ischemia-reperfusion injury and anthocyanin-rich diets have been shown to be associated with decre...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-2016-0667
更新日期:2017-08-01 00:00:00