Abstract:
:The site of exercise-induced muscle fatigue is suggested to be the muscle membrane, which includes the sarcolemma and T-tubule membrane; the excitability of the membrane is dependent on the membrane potential. Significant potassium flux from the intracellular space of contracting muscle may decrease the membrane potential to half its resting value. This is true for isolated muscle preparations as well as for the whole body exercise in humans. Specific K+ channels have been identified, that may account for the intracellular K+ loss. Calcium-sensitive K+ channels open when intracellular Ca2+ concentrations increase, as during excitation. ATP-sensitive K+ channels may be involved but may open only at ATP concentrations well below those attained at exhaustion. However, ATP may be compartmentalized and only the membrane-bound ATP concentration may be of significance. Ca2+ accumulation and ATP depletion cause cell destruction; these changes induce an increased K+ conductance, which may inactivate the membrane and consequently prevent tension development. It is hypothesized that such a safety mechanism is identical to the fatigue mechanism.
journal_name
Can J Physiol Pharmacoljournal_title
Canadian journal of physiology and pharmacologyauthors
Sjøgaard Gdoi
10.1139/y91-037subject
Has Abstractpub_date
1991-02-01 00:00:00pages
238-45issue
2eissn
0008-4212issn
1205-7541journal_volume
69pub_type
杂志文章,评审abstract::The effect of isoproterenol on mean right and left atrial pressures (RAP, LAP) and dimensions (RAD, LAD), and plasma immunoreactive atrial natriuretic factor (IR-ANF) was investigated in anesthetized rabbits. Infusion of isoproterenol (10 micrograms.kg-1.min-1 for 10 min) significantly increased plasma IR-ANF and hear...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y91-069
更新日期:1991-04-01 00:00:00
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::It has recently been demonstrated that the protein tyrosine phosphatase (PTP) PTP1B and the T-cell PTP (TC-PTP) target several substrates involved in immune cell signaling. Recent data have furthered the view of these 2 PTP members as key regulators of the immune response. This review will focus on the substrate speci...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章,评审
doi:10.1139/y06-012
更新日期:2006-07-01 00:00:00
abstract::Prolongation of bradykinin half-life following kininase inhibition has been proposed as the reason for the potentiation of kinin effects. We have reassessed this assumption by using three different isolated smooth muscle preparations and simultaneously studying the inhibition of kininase activity and the potentiation ...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y91-137
更新日期:1991-07-01 00:00:00
abstract::The level of circulating triacylglycerols is determined by the balance between their delivery into the plasma and their removal from it. Plasma triacylglycerols are derived either from dietary fat as chylomicrons or from endogenous hepatic synthesis as very low density lipoproteins. Their removal occurs through the ac...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章,评审
doi:10.1139/y91-242
更新日期:1991-11-01 00:00:00
abstract::The numbers and sizes of nerve fibres to the dorsal neck muscles, splenius, complexus and biventer cervicis have been examined in the cat. The total number of fibres is unusually high as is the content of sensory fibres (estimated as the loss of fibres after ganglionectomy). The fibre spectra of these sensory nerves h...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y76-043
更新日期:1976-06-01 00:00:00
abstract::The effects of localized distension of the pulmonary vein - left atrial junctions on plasma arginine vasopressin (AVP) have been examined in chloralose anaesthetized dogs. Pulmonary vein distension caused an increase in heart rate and a decrease in plasma AVP concentration. Cooling the vagosympathetic nerves to 10 deg...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y83-136
更新日期:1983-08-01 00:00:00
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 int...
journal_title:Canadian journal of physiology and pharmacology
pub_type:
doi:
更新日期:1996-03-01 00:00:00
abstract::The effect of ionizing radiation on jejunal blood flow was investigated in rats receiving whole-body exposure to 10 Gy gamma-radiation. Irradiation resulted in increased myeloperoxidase activity, indicative of neutrophil infiltration, and prostaglandin E2 synthesis by 2 h post-irradiation, but had no effect on leukotr...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y95-090
更新日期:1995-06-01 00:00:00
abstract::There is an increasing incidence of oxaliplatin (OXA)-induced hepatotoxicity. Therefore researchers' attention has been drawn to therapeutic alternatives that may decrease OXA-induced hepatotoxicity. Studies indicate that oxidative stress plays a major role in OXA-induced liver injury. Since several pharmacological ef...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-2020-0134
更新日期:2020-08-18 00:00:00
abstract::Natural rodent grooming and other instinctive behavior serves as a natural model of complex movement sequences. Rodent grooming has syntactic (rule-driven) sequences and more random movement patterns. Both incorporate the same movements--only the serial structure differs. Recordings of neural activity in the dorsolate...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y04-061
更新日期:2004-08-01 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::Sequestration of nitric oxide (NO) by subcellular fractions isolated from bovine pulmonary arterial medial layer (BPA) and rabbit platelets (RP) was studied utilizing a novel chemiluminescence--headspace gas technique. Sequestration in all fractions was similarly rapid (5 min) and remained constant for at least 30 min...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y93-142
更新日期:1993-12-01 00:00:00
abstract::Resting membrane potentials and membrane conductances of chick skeletal muscle in culture were determined from the 3rd to the 10th day after plating. The effect of tetraethylammonium (TEA) and of replacement of potassium with caesium on these parameters was investigated. Resting membrane potential (Em) rises during my...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y80-100
更新日期:1980-06-01 00:00:00
abstract::Male spontaneously hypertensive stroke-prone (SHRsp) rats were fed 4% NaCl diets containing either 0.75% (normal) K or 2.11% (high) K, starting at 6 weeks of age. After 8 months on these diets, 40 out of 58 SHRsp rats on the 0.75% K diet had died (69% mortality) versus 2 dead out of 95 on the 2.11% K diet (2% mortalit...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y86-145
更新日期:1986-06-01 00:00:00
abstract::Coronary flow was recorded from spontaneously beating isolated perfused hearts of rats and guinea pigs. Arachidonic acid (AA), in single bolus doses, produced a fast short lasting coronary constriction followed by a slow developing but persisting vasodilation. These reactions (biphasic type) were characteristic of the...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y84-211
更新日期:1984-10-01 00:00:00
abstract::The hypocalcaemic action of ethanol (3 g/kg body weight) was investigated in intact, thyroparathyroidectomized and antrectomized rats. It was found that ethanol administered either intraperitoneally or orally reduced plasma calcium concentrations within 30 min and that this response lasted for 8 h. Additional studies ...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y83-059
更新日期:1983-04-01 00:00:00
abstract::A semisynthetic chemical compound, demethyldiisoeugenol, concentration dependently inhibited platelet aggregation and ATP release stimulated by thrombin (0.1 U/mL), platelet-activating factor (2 ng/mL), arachidonic acid (100 microM), collagen (10 micrograms/mL), and U46619 (1 microM) in rabbit washed platelets. The IC...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-74-10-1111
更新日期:1996-10-01 00:00:00
abstract::A knowledge of the mechanical properties of valve tissue is a necessary prerequisite for a better understanding of valvular behavior and design of prosthetic heart valves. Elastic response of chordae tendineae under strain rates of 0.05 cm min(-1)(6.25% min(-1)) to 12.7 cm min(-1)(1600% min(-1)) were obtained by the a...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y75-048
更新日期:1975-06-01 00:00:00
abstract::Anesthetized dogs were prepared for the measurement of compliance of the inferior vena cava by placement of a catheter for pressure measurement and a pair of ultrasonic dimension transducers for the measurement of transverse diameter. Measurements of compliance were made in a control state, after the induction of carb...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y86-092
更新日期:1986-05-01 00:00:00
abstract::The precise neurobiological mechanisms of tramadol abuse underlying the cognitive function are still unknown. The aim of the present study was to examine the possible effects of intra-CA1 injections of N-methyl-d-aspartate (NMDA), a glutamate NMDA receptor (NMDAR) agonist, and d,l-2-amino-5-phosphonopentanoic acid (DL...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-2017-0228
更新日期:2018-01-01 00:00:00
abstract::The contractile recoverability of isolated portal veins made hypodynamic by removal of glucose from the perfusion medium by diverse exogenous substrates was studied. It was found that glucose, mannose, pyruvate, lactate, acetate, and butyrate readily restored contraction. The effects of anoxia and metabolic inhibitors...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y80-115
更新日期:1980-06-01 00:00:00
abstract::Atrial natriuretic peptide (ANP) and B-type natriuretic peptide (BNP) are cardiac hormones synthesized in and secreted from the heart. ANP and BNP bind the common receptor guanylyl cyclase-A (GC-A) and possess biological actions. Based on their diuretic, natriuretic, and vasodilating activities, they are now widely us...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章,评审
doi:10.1139/y11-022
更新日期:2011-08-01 00:00:00
abstract::17 beta-Hydroxy-11 beta(4-dimethylaminophenyl)-17 alpha-(1-propynyl)estra-4, 9-dien-3-one (RU486) inhibited the in vitro development of different stages of mouse preimplantation embryos under study. Two-celled embryos, morulae, and early blastocysts were obtained from B6D2F1 mice. The embryos were grown in Ham F-10 nu...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y90-220
更新日期:1990-11-01 00:00:00
abstract::The effects of magnesium (from 1.2 to 7.2 mM) were investigated in isolated perfused rat heart subjected to coronary artery ligation and reperfusion. Increasing magnesium concentrations, of the medium containing 3.00 mM of calcium, induced a significant bradycardia and a protective effect towards reperfusion arrhythmi...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y90-105
更新日期:1990-06-01 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::Prevention and treatment of Alzheimer disease are urgent problems for elderly people in developed countries. We previously reported that nobiletin, a poly-methoxylated flavone from the citrus peel, improved the symptoms in various types of animal models of memory loss and activated the cAMP responsive element (CRE)-de...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-2015-0394
更新日期:2016-07-01 00:00:00
abstract::The purposes of this review were twofold: to apply modern physicochemical principles to explain changes in acid-base regulation and the control of ventilation in human pregnancy; and to demonstrate the value of pregnancy as a model for the study of endocrine effects on physiological control systems. Application of P.A...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章,评审
doi:10.1139/cjpp-76-9-815
更新日期:1998-09-01 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::In recent experiments in conscious lambs, we showed that in addition to its well-known natriuretic and diuretic effects, i.v. injection of 2 mg/kg of furosemide resulted in a sustained increase in heart rate and an age-dependent increase in plasma renin activity. To determine whether these responses were dose dependen...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:
更新日期:1997-09-01 00:00:00