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 methacholine. Liquid agarose at 37 degrees C is injected into human lung segments to inflate them to a volume equivalent to total lung capacity. The agarose-filled lungs are then gelled by brief refrigeration and 0.5-mm-thick explants prepared by sectioning. The explants are cultured overnight under conventional conditions. Sections with airways cut in cross section are identified and placed on an inverted videomicroscope. Airway lumen area is then measured following administration of methacholine in increasing concentrations, permitting the construction of dose-response curves for each airway segment studied. This system thus lends itself to the study of the heterogeneity of airway responsiveness across the airway tree by permitting the study of distributions of airways. Using this approach, we have observed a very high degree of heterogeneity of responsiveness across the airways of human lungs. In this report, we review these findings and discuss the physiologic implications of heterogeneity.
journal_name
Can J Physiol Pharmacoljournal_title
Canadian journal of physiology and pharmacologyauthors
Minshall E,Wang CG,Dandurand R,Eidelman Dsubject
Has Abstractpub_date
1997-07-01 00:00:00pages
911-6issue
7eissn
0008-4212issn
1205-7541journal_volume
75pub_type
杂志文章abstract：:Dissociated neuronal cultures have become a popular tool to address a number of questions in neurobiology. These culture systems may provide useful paradigms to approach problems related to in vivo neurotoxicity of xenobiotics. The clinical spectra of vinca neurotoxicity and alcohol teratogenesis is reviewed, and some...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y84-172
更新日期：1984-08-01 00:00:00
abstract：:The most important reason for the non-approval and withdrawal of drugs by the Food and Drug Administration is hepatotoxicity. Therefore, this study was undertaken to evaluate the protective effects of hesperidin against cyclophosphamide (CYP)-induced hepatotoxicity in Wistar rats. The rats received a single intraperit...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/cjpp-2014-0204
更新日期：2014-09-01 00:00:00
abstract：:The major hallmark of rotator cuff tendinopathies (RCT) is the disorganization of tendon extracellular matrix (ECM) which is due to decrease in the collagen I-to-collagen III ratio. In addition, the pathology of tendon matrisome remains asymptomatic and hypoxia has been identified to be the priming signal to initiate ...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/cjpp-2020-0314
更新日期：2020-08-15 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：:Over the last 2 decades, mi(cro)RNAs have emerged as one of the key regulators of metabolic homeostasis. Most of the studies have highlighted that, in the cytoplasm, miRNAs directly bind to the 3'-UTR (untranslated region) of a mRNA. Conventional RNA-induced silencing complex (RISC) formation results in the post-trans...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章,评审
doi：10.1139/cjpp-2016-0580
更新日期：2017-10-01 00:00:00
abstract：:The intramuscular injection of aminooxyacetic acid (AOAA) into mice elevated the concentration of gamma-aminobutyric acid (GABA) in the brain, inhibited glutamic acid decarboxylase activity and delayed the onset of isonicotinic acid hydrazide induced seizures. Analyses of these results and of those obtained previously...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y76-074
更新日期：1976-08-01 00:00:00
abstract：:In this study, we examined the effect of hydrogen peroxide on the accumulation of various mRNAs encoding heat shock proteins (hsps) and proto-oncogenes in Xenopus A6 kidney epithelial cells. Hydrogen peroxide treatment enhanced the accumulation of hsp90, hsp70, hsp30, c-jun, c-fos, and actin mRNAs with distinct tempor...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y04-059
更新日期：2004-07-01 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：: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：:This study was designed to determine if tonic beta-adrenergic control of plasma renin activity (PRA) during dietary sodium restriction is due to stimulation of renal beta-adrenoceptors, extrarenal beta-adrenoceptors, or both. Experiments were performed in six conscious resting uninephrectomized dogs with chronically i...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y95-171
更新日期：1995-08-01 00:00:00
abstract：:The sodium-hydrogen exchanger (NHE) helps the cell to recover from intracellular acidosis. In this study, we have investigated the effect of HOE 642 (a specific NHE1 blocker) on papillary muscles from rats and guinea pigs during transient acidosis and PKC activation by recording developed force (DF), action potential ...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y03-091
更新日期：2003-10-01 00:00:00
abstract：:Tension responses to ramp shortening of varying speed in whole muscle or single fibres from the plateau of an isometric tetanus, revealed at least two distinct phases. There was a fast initial drop in tension followed by a change of slope and a definite inflexion on the tension record. As the velocity of the imposed l...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y85-268
更新日期：1985-12-01 00:00:00
abstract：:To investigate the capacity of efferent sympathetic neurons to modulate the failing heart, stellate ganglion stimulation was performed in dogs with biventricular heart failure induced by rapid ventricular pacing (240 beats/min) for 4-6 weeks. Less noradrenaline was released from cardiac myoneural junctions into corona...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：
更新日期：1996-09-01 00:00:00
abstract：:Pial arteriolar diameter changes inversely with changes in systemic arterial blood pressure. Such changes are consistent with autoregulatory functions. These responses are reduced by a brief period of hypoxia followed by reoxygenation. By using an open cranial window preparation we assessed the changes in pial arterio...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y89-067
更新日期：1989-05-01 00:00:00
abstract：:Curare action on nicotinic acetylcholine receptors has a number of facets, of which the best known is competitive antagonism. Here we describe the weak agonist action of 10(-5) M curare on the murine skeletal muscle cell line, G8. Although curare induces no depolarization in G8 cells, single-channel recordings reveal ...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y89-025
更新日期：1989-02-01 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：: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：:The force generated by tracheal spirals and lung parenchymal strips from normal and ovalbumin-sensitized guinea pigs was measured in vitro, after challenge with histamine, carbachol, leukotriene (LT) C4, LTD4, or a prostaglandin endoperoxide analog (U-44069). The responses and sensitivity of airway tissues to the abov...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y83-133
更新日期：1983-08-01 00:00:00
abstract：:Rapamycin, a new antifungal antibiotic, was found to inhibit the immune response in rats. It totally prevented the development of two experimental immunopathies (experimental allergic encephalomyelitis (EAE) and adjuvant arthritis (AA)) and the formation of humoral (IgE-like) antibody. It was about half as potent as c...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y77-007
更新日期：1977-02-01 00:00:00
abstract：:Inorganic vanadium has been shown, both in vivo and in vitro, to have insulin-mimetic properties. A new organic vanadium complex, bis(maltolato)oxovanadium(IV) (BMOV), was developed to increase the absorption of vanadium from the gastrointestinal tract, thereby reducing the dose of vanadium necessary to produce glucos...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y93-041
更新日期：1993-03-01 00:00:00
abstract：:Radioactively labelled microspheres (15 micron diameter) were used to measure cardiac output (CO) distribution and blood flows in spleen, kidneys, and skeletal muscle before and after normovolemic anemia or polycythemia in anesthetized rats. Hematocrits were changed from 45 to 33% or from 45 to 59% by an exchange tran...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y80-069
更新日期：1980-04-01 00:00:00
abstract：:Phosphofructokinase activity was measured in the sciatic nerve of streptozotocin-induced diabetic and nondiabetic rats. Average steady-state phosphofructokinase activity was obtained from three consecutive segments of the mid-femoral region in the left sciatic nerve in both diabetic (4 and 24 weeks) and nondiabetic, a...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y90-198
更新日期：1990-10-01 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：:Despite the widespread use of furosemide in the treatment of various fluid and electrolyte disorders in the preterm and term human infant and child, the physiological effects of this potent diuretic agent on renal function and renin release during postnatal maturation are poorly understood. To test the hypothesis that...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y95-015
更新日期：1995-01-01 00:00:00
abstract：:The effect of adrenaline on the membrane transport of 3-methylglucose was studied in perifused isolated rat left atria that had been fully arrested. In this preparation a high concentration of adrenaline stimulated and a low one decreased sugar transport. The stimulatory effect was strongly inhibited by the beta-adren...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y76-099
更新日期：1976-10-01 00:00:00
abstract：:The present study focused on the interactive pain regulation of endokinin A/B (EKA/B, the common C-terminal decapeptide in EKA and EKB) or endokinin C/D (EKC/D, the common C-terminal duodecapeptide in EKC and EKD) on chimeric peptide MCRT (YPFPFRTic-NH2, based on YPFP-NH2 and PFRTic-NH2) at the supraspinal level in mi...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/cjpp-2015-0554
更新日期：2016-09-01 00:00:00
abstract：:The inhibition of hepatic microsomal aryl hydrocarbon hydroxylase (AHH) activity by SKF 525-A in vitro was studied in hepatic microsomes from rats of varying age, sex hormone status, and drug treatment. The concentration of SKF 525-A required to produce a 50% inhibition of AHH activity, the IC50, was determined for th...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y82-156
更新日期：1982-08-01 00:00:00
abstract：:New methods for chronic instrumentation of the newborn piglet are described, which allow continuous monitoring of not only pressures in the pulmonary artery and aorta but also in the left and right atria, pulmonary vein, as well as main branch pulmonary artery flows. Changes in pulmonary vascular tone to short-acting ...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y87-126
更新日期：1987-05-01 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 effect of estrogen on the passive characteristics of arteries is not known. We hypothesized that estrogen would increase arterial distensibility as part of its protective effect on the vasculature. Female Sprague-Dawley rats were ovariectomized at 11 weeks of age. One group received a placebo (n = 6), while two ot...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/cjpp-77-1-75
更新日期：1999-01-01 00:00:00
