Abstract:
:The study was carried out to determine whether the diminished release of norepinephrine (NE) upon sympathetic activation in the presence of sotalol can be attributed to the blockade of beta-adrenoceptors in the liver. NE release from the liver was measured in hepatic venous blood collected during direct hepatic nerve stimulation in anesthetized dogs. The mean basal NE concentration in hepatic venous and aortic blood was 0.046 +/- 0.003 and 0.244 +/- 0.041 ng/mL, respectively. NE release increased significantly as stimulation frequency increased, while aortic NE concentration remained unchanged. The increasing response of NE release upon stimulation in the vehicle control group remained stable during the whole experimental period. In dogs treated with sotalol (5 mg/kg, i.v.), NE release was reduced approximately by 30-43%, and the difference was statistically significant (P less than 0.01) at 8 Hz. (+/-)-Propranolol (2.5 mg/kg, i.v.) tended to diminish it, but the difference was not significant. (-)-Propranolol (0.1 mg/kg, i.v.) did not alter NE release at any frequency tested. The beta-blocking action of these drugs in the liver, as determined by the antagonism against the hepatic arterial vasodilating response to isoproterenol, was most effective with (+/-)-propranolol (100%), followed by (-)-propranolol (90%) and sotalol (70%). The results suggest that the inhibitory effect of sotalol on NE release may be related to a mechanism other than its beta-blocking action in the dog liver.
journal_name
Can J Physiol Pharmacoljournal_title
Canadian journal of physiology and pharmacologyauthors
Yamaguchi Ndoi
10.1139/y85-234subject
Has Abstractpub_date
1985-11-01 00:00:00pages
1423-8issue
11eissn
0008-4212issn
1205-7541journal_volume
63pub_type
杂志文章abstract::Cerebrocrast is a novel lipophilic dihydropyridine derivative with potential neuroprotective and antidiabetic properties. We have analyzed its interaction with L-type (CaV1.2b) and T-type (CaV3.1) calcium channels using a whole-cell patch clamp in HEK 293 cells. Cerebrocrast inhibited current flux through both CaV1.2b...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y09-086
更新日期:2009-11-01 00:00:00
abstract::Several studies have utilized the spontaneously hypertensive (SHR) diabetic rat to document the synergistic deleterious consequences of diabetes and hypertension on various organ systems. However, whether these effects are due entirely to the overlapping pathological states or partially result from a greater susceptib...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:
更新日期:1996-11-01 00:00:00
abstract::The role of leukotriene D4 (LTD4) as a mediator of immediate hypersensitivity reactions in the guinea-pig conjunctiva was examined using a potent, second-generation LTD4 receptor antagonist, MK-571 (also known as L-660,711). The microvascular permeability changes in the guinea-pig conjunctiva following challenge with ...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y89-132
更新日期:1989-08-01 00:00:00
abstract::In Canada, the use of botanical natural health products (NHPs) for anxiety disorders is on the rise, and a critical evaluation of their safety and efficacy is required. The purpose of this study was to determine whether commercially available botanicals directly affect the primary brain enzymes responsible for gamma-a...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/Y07-083
更新日期:2007-09-01 00:00:00
abstract::This paper provides a brief overview of the adaptive control of prehension. Several primary issues for research in the field are considered. One pertains to the stages of prehensile activity, with particular concern for the kinematic control of precontact phases, and the coordination of load and grip forces following ...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章,评审
doi:10.1139/y94-074
更新日期:1994-05-01 00:00:00
abstract::Ovalbumin (OA) and the calcium ionophore A23187 induced a dose-dependent contraction of guinea pig tracheal strips. The OA-induced contraction (of sensitized trachea) consisted of an initial peak concentration, maximal between 5 and 10 min, followed by a very gradual decline from the peak. On the other hand, A23187 in...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y81-158
更新日期:1981-10-01 00:00:00
abstract::Rats were fed on a diet containing 1% beta-guanidinopropionate (Gp) to deplete their muscles of creatine. The apparent energy reserves (creatine phosphate (CrP) + ATP) of rested state diaphragm muscle strips were found to be 79% depleted by this treatment. To determine if the effective energy reserves for contraction ...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y82-019
更新日期:1982-02-01 00:00:00
abstract::Redistribution of blood flow away from resting skeletal muscles does not occur during anemic hypoxia even when whole body oxygen uptake is not maintained. In the present study, the effects of sympathetic nerve stimulation on both skeletal muscle and hindlimb blood flow were studied prior to and during anemia in anesth...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y88-019
更新日期:1988-02-01 00:00:00
abstract::A principal step in the process leading to muscle contraction is the intracellular release of Ca2+. We have detected and compared some physical and chemical events that reflect Ca2+ release in contracting frog skeletal muscle cells, described the effects of some agents that are believed to alter intracellular Ca2+ rel...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y82-068
更新日期:1982-04-01 00:00:00
abstract::In assessing the role that atrial natriuretic peptide (ANP) might have in the homeostasis of fluid volume and blood pressure, it is important to define the physiological and pathophysiological conditions that determine its release into the circulation. There is substantial evidence that ANP is released through atrial ...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章,评审
doi:10.1139/y87-262
更新日期:1987-08-01 00:00:00
abstract::The causes of reduced levels of omega-3 and omega-6 highly unsaturated fatty acids ("HUFA deficiency") in heart failure remain unresolved. HUFA profiles were examined in the serum of 331 patients with failing versus nonfailing heart disease. Arachidonic acid was positively correlated (P < 0.001) with eicosapentaenoic ...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 临床试验,杂志文章
doi:10.1139/y11-101
更新日期:2012-01-01 00:00:00
abstract::The vascular inflammatory process has been suggested to play a key role in the initiation and progression of atherosclerosis, a major complication of diabetes mellitus. Thus, in this study, we attempted to determine whether 2 structurally related flavonoids found in Cyclopia subternata, vicenin-2 and scolymoside, can ...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-2015-0215
更新日期:2016-03-01 00:00:00
abstract::Hyperglycemia in diabetes induces increased endothelin-1 (ET-1) production in the retina, kidney, and heart that may lead to hemodynamic impairment, permeability alteration, and increased extracellular matrix (ECM) protein production. Chronically elevated blood glucose levels may cause oxidative stress in these target...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/Y08-033
更新日期:2008-06-01 00:00:00
abstract::Raloxifene (RLX), a selective oestrogen receptor modulator, has oestrogen-agonist effects on bone, lipoproteins, and homocysteine and oestrogen-antagonist activity in the breast and uterus, positioning it as a potential drug for long-term prevention of coronary heart disease in postmenopausal women. To further evaluat...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 临床试验,杂志文章
doi:10.1139/y10-002
更新日期:2010-05-01 00:00:00
abstract::The regulation of amino acid transport by angiotensin II (AII) and cyclic AMP (cAMP) was assessed in cultured vascular smooth muscle cells, using a nonmetabolizable amino acid, alpha-[3H]aminoisobutyric acid (AIB). An exposure time in excess of 2 h was required for AII to elicit a stimulatory response, the magnitude o...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:
更新日期:1996-02-01 00:00:00
abstract::In mature (450-600 g) 21 degrees C-acclimated male rats, anaesthetized with urethane, blood flow (measured by the radioactive microsphere technique) to brown adipose tissue (BAT) was determined during the infusion of the beta-adrenoceptor agonist BRL 28410 or noradrenaline bitartrate at doses chosen to give similar in...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y86-189
更新日期:1986-08-01 00:00:00
abstract::Cyclic AMP response element (CRE) binding protein (CREB) is a nuclear transcription factor that regulates the transcription of several genes containing the CRE sites on their promoters. CREB is activated by phosphorylation on a key serine residue, Ser311, in response to a wide variety of extracellular stimuli includin...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-2020-0531
更新日期:2021-01-01 00:00:00
abstract::Urinary output of Na+ and K+, and volume of urine have been studied in conscious, unrestrained, water-loaded male rats following the intraseptal injection of catecholamines. Natriuresis and kaliuresis increased after injecting noradrenaline (NA), the intensity being dose related. The dose-response curve suggests that ...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y76-034
更新日期:1976-06-01 00:00:00
abstract::In vivo fatty acid synthesis and the pathways of glycerol-3-phosphate (G3P) production were investigated in brown adipose tissue (BAT) from rats fed a cafeteria diet for 3 weeks. In spite of BAT activation, the diet promoted an increase in the carcass fatty acid content. Plasma insulin levels were markedly increased i...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y08-052
更新日期:2008-07-01 00:00:00
abstract::Cardiac injury and loss of cardiomyocytes is a causative as well as a resultant condition of cardiovascular disorders, which are the leading cause of death throughout the world. This loss of cardiomyocytes cannot be completely addressed through the currently available drugs being administered, which mainly function on...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章,评审
doi:10.1139/cjpp-2014-0468
更新日期:2015-10-01 00:00:00
abstract::The main factors of myocardial ischemia are hypoxia, substrate deprivation, acidosis, and high extracellular potassium concentration ([K+]e), but the influence of each of these factors has not yet been evaluated in a cardiomyocyte (CM) culture system. Electromechanical responses to the individual and combined componen...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y02-143
更新日期:2002-12-01 00:00:00
abstract::Alterations in electrical conductivity between smooth muscle cells (SMCs) can alter the spread and effectiveness of electromechanical SMC contraction. We attempted to determine whether alterations in pressure-dependent constriction (PDC) occurring in relation to stroke development within the middle cerebral arteries (...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:
更新日期:1998-02-01 00:00:00
abstract::Angiotensin II (AngII) plays an important role in the regulation of vascular smooth muscle function. However, little is known about AngII and its receptors AT1 (AT1R) and AT2 (AT2R) and their modulation of intracellular calcium in vascular endothelial cells (VECs) in general and more particularly of human origin. Usin...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-2017-0416
更新日期:2017-10-01 00:00:00
abstract::The risk assessment of mycotoxins is made up of two major components: an exposure assessment and a hazard assessment. There are many uncertainties in both of these components. This paper will briefly discuss the various aspects of the risk assessment process as it applies to mycotoxins and will then focus mainly on so...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章,评审
doi:10.1139/y90-155
更新日期:1990-07-01 00:00:00
abstract::Gripp-Heel is a homeopathic preparation frequently used in the treatment of respiratory viral infections such as various types of influenza and the common cold. The antiviral activity of Gripp-Heel was studied in vitro on human pathogenic enveloped and nonenveloped RNA and DNA viruses. Before the antiviral assays, in ...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/Y07-100
更新日期:2007-11-01 00:00:00
abstract::The vasculature of the mammalian renal medulla is complex, having neither discrete input nor output. There is also efficient countercurrent exchange between ascending and descending vasa recta in the vascular bundles. These considerations have hampered measurement of medullary blood flow since they impose pronounced c...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章,评审
doi:10.1139/y86-151
更新日期:1986-07-01 00:00:00
abstract::The development of the febrile response to E. coli lipopolysaccharide (1.5 micrograms/kg, i.v.) in thyroid-deficient rabbits has been studied. Twenty-eight New Zealand White rabbits weighing 2.1-2.3 kg were used. Hypothyroidism was induced by treatment with propylthiouracil (100 or 200 mg/kg body wt./15 days). Thyroid...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y87-209
更新日期:1987-06-01 00:00:00
abstract::The rate of glucose oxidation of fresh corneas of guinea pigs at different ages has been determined. Full-thickness corneal discs, 4 mm in diameter, were incubated in radioactive glucose solution. The quantity of the released CO2 was expressed in terms of the corneal discs, their dry weights, and DNA and protein conte...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y79-174
更新日期:1979-10-01 00:00:00
abstract::In recent years a considerable amount of experimental evidence has suggested that forebrain structures are involved in the pathogenesis of high arterial pressure (AP). However, little is known about the location and function of these supramedullary structures in the hypertensive process. This report reviews a series o...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y87-248
更新日期:1987-08-01 00:00:00
abstract::Our previous studies have suggested that GATA-4 increases the differentiation of bone-marrow-derived mesenchymal stem cells (MSCs) into cardiac phenotypes. This study further investigated whether GATA-4 enhances MSC-mediated cardioprotection following hypoxia. MSCs were harvested from rat bone marrow and transduced wi...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-2014-0009
更新日期:2014-08-01 00:00:00