Abstract：
:To investigate the contribution of pulmonary surfactant to a low airflow resistance through narrow conducting airways, a system was developed with which it was possible to determine the resistance meeting a steady flow of air at 0.5 mL/min. The airflow, delivered by an infusion pump, entered the extreme periphery of a conducting airway in an excised rat lung and exited through the trachea. The resistance was determined by measuring the pressure of the air entering the lung. If the airway remained open, the pressure was only slightly above zero; when a blocking liquid column formed in the lumen of the airway, the pressure increased rapidly but dropped abruptly as the liquid was pushed away into a wider airway section. When endogenous pulmonary surfactant was removed with a saline lavage, the airway was blocked almost constantly by an endless re-formation of liquid columns. Consequently, during a 4-min period of pressure recording, free airflow was observed only rarely. However, administration of aerosol surfactant increased the duration of free airflow in relation to the volume administered. After an injection of 80 mL of aerosol surfactant, the airway stayed open 89 +/- 3% of the 4-min recording time compared with only 28 +/- 5% when the same volume of air (80 mL) without surfactant had passed through the airway (p < 0.0001). We conclude that surfactant contributes to a free airflow through conducting airways and may have an important role in the maintenance of low airway resistance.
journal_name
Can J Physiol Pharmacoljournal_title
Canadian journal of physiology and pharmacologyauthors
Enhorning G,Yarussi A,Rao P,Vargas Isubject
Has Abstractpub_date
1996-06-01 00:00:00pages
687-91issue
6eissn
0008-4212issn
1205-7541journal_volume
74pub_type
杂志文章abstract：:Previous studies have demonstrated that the D-enantiomer of isoidide dinitrate (IIDN) is 10-fold more potent than the L-enantiomer for relaxation and cyclic GMP accumulation in isolated rat aorta. To test whether preferential biotransformation of D-IIDN to a species that activates guanylate cyclase is the basis for th...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y89-225
更新日期：1989-11-01 00:00:00
abstract：:The sarco(endo)plasmic reticulum calcium ATPase (SERCA) is responsible for transporting calcium (Ca(2+)) from the cytosol into the lumen of the sarcoplasmic reticulum (SR) following muscular contraction. The Ca(2+) sequestering activity of SERCA facilitates muscular relaxation in both cardiac and skeletal muscle. Ther...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章,评审
doi：10.1139/cjpp-2014-0463
更新日期：2015-10-01 00:00:00
abstract：:Neuropeptide Y (NPY(1-36)), a sympathetic cotransmitter and neurohormone, has pleiotropic activities ranging from the control of obesity to anxiolysis and cardiovascular function. Its actions are mediated by multiple Gi/o-coupled receptors (Y1-Y5) and modulated by dipeptidyl peptidase IV (DPPIV/cd26), which inactivate...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章,评审
doi：10.1139/y03-006
更新日期：2003-02-01 00:00:00
abstract：:The purpose of this study was to determine the interaction of three factors that modify twitch contraction amplitude in the rat gastrocnemius muscle in situ: posttetanic potentiation, fatigue, and caffeine. Posttetanic (200 Hz for 1 s) twitch responses were observed before and after 15 Hz stimulation for 6 min (group ...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y87-046
更新日期：1987-02-01 00:00:00
abstract：:Electrophysiological studies were performed on in vitro slice preparations of sympathetic ganglia excised from peripherally perfused, brain-dead human donors. The intracellular recordings in 16 neurons showed resting potentials and input resistances mostly in the ranges reported for sympathetic neurons in other mammal...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y88-138
更新日期：1988-06-01 00:00:00
abstract：:The cannabinoid system has been suspected to play a role in the mechanisms of action of dipyrone and paracetamol. Our purpose was to measure the local endocannabinoid and N-acylethanolamide levels in the brain and spinal cord of rats following dipyrone and paracetamol administration. Nociception was assessed 1, 5, and...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/cjpp-2019-0015
更新日期：2019-11-01 00:00:00
abstract：:Normal penile erectile function is dependent on arterial adequacy, appropriate venous occlusion, neurohumoral factors, and finally the relaxation of penile cavernous trabecular smooth muscle. The present experiments were designed to test whether compounds related to endothelium-derived relaxing factor have a role in p...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y89-014
更新日期：1989-01-01 00:00:00
abstract：:Temporary block of glycolysis by 2-deoxy-D-glucose (2-DG) reversibly suppresses synaptic transmission in the CA1 region of hippocampal slices. Recovery of responses is followed by a sustained potentiation of field excitatory postsynaptic potentials (EPSPs) (2-DG-LTP). To investigate the mechanisms involved in this typ...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：
更新日期：1997-05-01 00:00:00
abstract：:We investigated the effects of 4% fructose plus moderately high salt (MHS) (4% NaCl) treatment on tissue aldehyde conjugates, platelet cytosolic free calcium ([Ca2+]i), renal morphology, and systolic blood pressure (SBP) in Wistar-Kyoto rats, and whether these effects were reversible (R) after withdrawal of treatment....
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y06-080
更新日期：2007-03-01 00:00:00
abstract：:In vitro coronary artery responsiveness to angiotensin I, angiotensin II, noradrenaline, phenylephrine, BHT 920, and potassium chloride together with functional relaxation to acetylcholine was investigated in dogs with pacing-induced heart failure treated with enalapril (oral administration of 10 mg.day-1) for a mean ...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y92-199
更新日期：1992-10-01 00:00:00
abstract：:Hypothermia increases the sensitivity of isolated cardiac muscle to stimulation by beta-adrenoceptor agonists. The purpose of this study was to determine pharmacologically whether this supersensitivity is associated with a change in the affinity of agonists for the receptor. The positive inotropic and chronotropic res...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y83-088
更新日期：1983-06-01 00:00:00
abstract：:In order to understand the mechanisms of exercise intolerance and muscle fatigue, which are commonly observed in congestive heart failure, we studied sarcoplasmic reticulum (SR) Ca(2+)-transport in the hind-leg skeletal muscle of rats subjected to myocardial infarction (MI). Sham-operated animals were used for compari...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y04-051
更新日期：2004-07-01 00:00:00
abstract：:Liver blood flow and hepatic uptake of some indicator substances have been reported to fall with age in both rats and humans. We used an isolated liver system, which was perfused in one pass with hemoglobin free buffer, to investigate the effect of albumin concentration, buffer flow rate, and age upon hepatic clearanc...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y88-091
更新日期：1988-05-01 00:00:00
abstract：:Some current questions regarding muscle afferent receptors are discussed. These include the significance of variable distribution patterns of muscle spindles in different muscles and of differences in intrinsic spindle morphology. The significance of the very large and variable population of small myelinated afferent ...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y81-100
更新日期：1981-07-01 00:00:00
abstract：:Natural products from plants such as flavonoids are potential drugs to overcome multidrug resistance (MDR) in cancer treatments. However, their modes of action are still unclear. In this study, the effects of quercetin on mitochondrial membrane potential (DeltaPsim) change as well as quercetin's ability to induce apop...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y04-113
更新日期：2004-12-01 00:00:00
abstract：:Several lines of evidence suggest that the responsiveness of the airways is heterogeneous, although the magnitude of this heterogeneity has not been quantified. We have developed a videomicroscopic method that allows the measurements of the responsiveness of individual explanted airways to contractile agonists such as...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：
更新日期：1997-07-01 00:00:00
abstract：:Agelasimine A and agelasimine B, two novel compounds related to adenine, have been isolated from the orange sponge, Agelas mauritiana, and have been tested for a variety of biological activities. Both compounds inhibited proliferation of cultured L1210 leukemia cells at nanomolar concentrations with accumulation in th...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y89-045
更新日期：1989-04-01 00:00:00
abstract：:As an activator of AMPK, the effect of AICAR on insulin signaling has not been investigated extensively. PI3K-Akt is a critical node involved in the insulin signaling pathway. We observed that concomitant with the activation of AMPK by AICAR, the protein level of PI3K p85α and the insulin-induced phosphorylation of Ak...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/cjpp-2015-0159
更新日期：2016-02-01 00:00:00
abstract：:In 2-kidney, 1-clip hypertensive rats, the time course of changes in blood pressure (BP), heart rate, activity of the sympathetic nervous system and the renin-angiotensin system, plasma and blood volumes, left ventricular (LV) and right ventricular (RV) weight, and LV dimensions were evaluated during treatment with hy...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y86-257
更新日期：1986-12-01 00:00:00
abstract：:Endometritis is one of the main diseases that harms the dairy cow industry. Tanshinone IIA (TIIA), a fat-soluble alkaloid isolated from Salviae miltiorrhizae, has been reported to have potent anti-inflammatory properties. However, the anti-inflammatory effects of TIIA on a mouse model of lipopolysaccharide (LPS)-induc...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/cjpp-2015-0003
更新日期：2015-11-01 00:00:00
abstract：:Carbon monoxide (CO), a vasodilator, has been implicated as an activator of soluble guanylyl cyclase (sGC) to effect smooth muscle relaxation; however, this idea has not received universal support. The purpose of this study was to examine the effects of the sGC inhibitor 1H-[1,2,4]oxadiazolo[4,3-alpha]quinoxalin-1-one...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：
更新日期：1997-08-01 00:00:00
abstract：:This report reviews the research and mentoring career of Richard B. Stein (1940-). In 1962, he completed a B.S. degree in physics at the Massachusetts Institute of Technology, USA, and thereafter an M.A. (1964), Ph.D. (1966), and postdoctoral training (1966-68) at the University of Oxford, UK. He subsequently assumed ...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 传,历史文章,杂志文章
doi：10.1139/y04-063
更新日期：2004-08-01 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：:Our objective was to investigate the effects of chronic excess iodine intake on thyroid functions and thyroid oxidative stress state in hypothyroid rats. Sixty rats were divided into euthyroid and hypothyroid (thiocyanate-induced) groups with or without administration of excess iodine (3000 or 6000 μg/L) for 8 weeks. ...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y2012-046
更新日期：2012-05-01 00:00:00
abstract：:Infarct-like lesion induced by isoprenaline is a well-known model to study myocardial infarction (MI). Vitamin D has been shown to have anti-inflammatory and antioxidant effects. Recent studies highlighted cross talk between vitamin D and peroxisome proliferator-activated receptor gamma (PPAR-γ). The present study was...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/cjpp-2016-0150
更新日期：2017-06-01 00:00:00
abstract：:Studies were conducted to determine whether Na-K ATPase or a second species of digitalis receptors in canine cardiac sarcolemma membrane preparations is associated with the positive inotropic action of nontoxic concentrations of ouabain. [3H]ouabain association and dissociation experiments using highly enriched sarcol...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y85-083
更新日期：1985-05-01 00:00:00
abstract：:The responses of the circular muscle of canine colon to stimulation of intrinsic nerves and to the probable mediators of these nerves were studied in vivo. In vivo studies were carried out using close intra-arterial injections and local field stimulation of proximal, mid-, and distal colon while recording circumferent...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y88-060
更新日期：1988-04-01 00:00:00
abstract：:We used thermoluminescence, electron spin resonance, and viscosimetric measurements to establish whether or not a spice had been irradiated. Thermoluminescence, using the 1788 EN official protocol with an alternative method for the extraction of mineral impurities, led to proof of irradiation or proof of no treatment....
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：
更新日期：2001-02-01 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 Symposium includes 15 presentations and an editorial review dealing with prorenin activation and function. It comes 20 years after prorenin was first reported in various contexts and attracted attention because of its connection with renin--angiotensin, its high concentration relative to renin in the blood, and i...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 社论,评审
doi：10.1139/y91-193
更新日期：1991-09-01 00:00:00
