Abstract:
:Using conventional intracellular microelectrode techniques, the membrane potential (Em) of vascular smooth muscle cells in isolated segments of thoracic rat aorta was measured. The influence of exogenous and of endothelium-derived nitric oxide on the Em was assessed, and the involvement of glibenclamide-sensitive channels in the observed membrane hyperpolarization was investigated. Exposures of the aorta strips to sodium nitroprusside (10(-8)-10(-5) M) caused a concentration-dependent and endothelium-independent hyperpolarization. Maximal hyperpolarization (5.7 +/- 0.4 mV) was obtained with 10(-5) M sodium nitroprusside. Acetylcholine (10(-8)-10(-5) M produced endothelium-dependent hyperpolarizations. At low concentrations, a slow Em change was elicited, which was sustained in the presence of the vasodilator. Higher concentrations of acetylcholine caused hyperpolarizations consisting of an initial transient peak followed by a more sustained component. Pre-exposure to Ng-nitro-L-arginine (L-NNA, 2 x 10(-4) M), which depolarized Em by 2.5 +/- 0.7 mV, significantly attenuated the later component of hyperpolarizations, indicating that it is NO dependent. Glibenclamide (10-5 M) did not significantly affect the hyperpolarization induced by 10(-6)-10(-5) M sodium nitroprusside nor the maintained component of hyperpolarization induced by 10(-5) M acetylcholine. It is concluded that the hyperpolarization caused by exogenous or endogenous NO in the rat aorta is not mediated by activation of glibenclamide-sensitive potassium channels.
journal_name
Can J Physiol Pharmacoljournal_title
Canadian journal of physiology and pharmacologyauthors
Vanheel B,Van de Voorde Jsubject
Has Abstractpub_date
1997-12-01 00:00:00pages
1387-92issue
12eissn
0008-4212issn
1205-7541journal_volume
75pub_type
杂志文章abstract::Experiments were done for indentification and localization of certain structural changes at different levels of jejunal villus of the hamster during positive and negative water transport across the intestine in vivo and in vitro. Positive transport occurred when the mucosal surface of the intestine was bathed (in vitr...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y75-063
更新日期:1975-06-01 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 influence of external potassium Ko and tetraethylammonium on the cellular K content of hypoxic myocardium was investigated. Perfused rabbit hearts were submitted to 60 min hypoxia in medium containing 5 mM K throughout or either low (1.5 mM) or high (10 mM) K during the last 20 min of hypoxia. Paced electrical act...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y87-138
更新日期:1987-05-01 00:00:00
abstract::Caffeine has been reported to have a positive and (or) a negative inotropic effect on cardiac muscle. In this study, the force-frequency and postrest characteristics of rat atrium were studied in the presence of caffeine (1.0-10 mM) to see if the interval between beats affected the response of cardiac muscle to caffei...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y92-034
更新日期:1992-02-01 00:00:00
abstract::Heme oxygenase (HO) has a central role in cellular antioxidant defences and vascular protection, and it may mediate pleiotropic actions of drugs used in cardiovascular therapy. We investigated whether long-term use of statins upregulates HO activity and increases carbon monoxide (CO) and bilirubin levels in vivo. Adul...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y07-077
更新日期:2007-08-01 00:00:00
abstract::The purpose of this study was to investigate the effects of bosentan, a mixed endothelin receptor A and B subtype antagonist, on myocardial ischemia-reperfusion injury and to explore the influence of the timing of bosentan administration on its cardioprotective effects. Adult rat hearts were perfused by the Langendorf...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y05-014
更新日期:2005-03-01 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::Hearts from rats pretreated either with L-triiodothyronine (T3) or with L-thyroxine (T4) exhibited changed function curve characteristics on the working heart apparatus compared with hearts from vehicle-treated rats. There was no supersensitivity of the hyperthyroid myocardium to the inotropic effect of isoproterenol ...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y83-198
更新日期:1983-11-01 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::The purpose of this study was to investigate the cardiac adrenergic neuronal changes induced by diabetes and hypertension by using an analogue of norepinephrine, meta-iodobenzylguanidine (MIBG), and to compare these changes with the contractile state of ventricular papillary muscle. The tissue concentration of norepin...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y94-164
更新日期:1994-10-01 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::The metabolic effect of intravenous infusion of ammonium chloride (60 mumol/(kg body weight.min] was compared in five sheep before and after adrenal denervation. Adrenal denervation completely abolished the hyperglycemic effect of ammonium chloride, diminished the rise of pyruvate and lactate concentration, and failed...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y89-168
更新日期:1989-09-01 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::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::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::We examined the interaction of smooth muscle myosin with alpha-actin and beta-actin isoforms during the contraction of A7r5 smooth muscle cells and rat aortic smooth muscle. The techniques of confocal microscopy and fluorescence resonance energy transfer (FRET) analysis were utilized in examining A7r5 cells and rat ao...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y09-008
更新日期:2009-05-01 00:00:00
abstract::The development of cardiac hypertrophy was examined in rats given ethanol in a nutritionally adequate, liquid diet mixture, by intubation, in severely intoxicating doses at 8-h intervals for up to 96 h, alone or in combination with prazosin. Other groups of rats received isocalorically paired quantities of maltose-dex...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y89-040
更新日期:1989-03-01 00:00:00
abstract::Cumulative data suggest the significant role of the renin-angiotensin system in the development of the pathological consequences of diabetes mellitus (DM). Newly synthesized AT2 receptor agonists gained importance as a target for creating new antihypertensives. The aim of the present work was to study the effects of p...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-2017-0428
更新日期:2018-05-01 00:00:00
abstract::The role that thromboxane A2 plays in contractions induced by leukotriene D4 in guinea-pig isolated lung parenchyma was investigated under equilibrium conditions. Lung tissue generated thromboxane A2 and prostacyclin spontaneously as evidenced by the slow accumulation of their biologically inactive metabolites, thromb...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y87-230
更新日期:1987-07-01 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::There is increasing evidence for a beneficial effect of ginseng on cardiac pathology. Here, we determined whether North American ginseng can modulate the deleterious effects of the β-adrenoceptor agonist isoproterenol on cardiac hypertrophy and function using in vitro and in vivo approaches. Isoproterenol was administ...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-2016-0337
更新日期:2016-12-01 00:00:00
abstract::For 10 days, dogs were fed a normal salt diet containing 70 mequiv. Na+/day (NSD) followed by a high salt diet containing 170 mequiv. Na+/day (HSD) or 240 mequiv. Na+/day (VHSD), or the order was reversed. K+ in these diets was fixed at 40 mequiv./day. The different diets did not influence the basal level of serum cat...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y80-164
更新日期:1980-09-01 00:00:00
abstract::Myometrial tissues from guinea pigs were quantitatively examined for gap junctions in electron micrographs. Small numbers of gap junctions were present between smooth muscle cells in myometria of pregnant guinea pigs at days 50 and 65 of gestation. The junctions increased in number and size at parturition on day 69 an...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y82-047
更新日期:1982-03-01 00:00:00
abstract::Using a time-lapse cinephotomicrographic technique, the locomotory paths taken by lymphocytes have been shown to satisfy the requirements for a continuous-time Markov chain analysis consisting of four directional states defined by the four quadrants of a Cartesian plane and state 0 in which the cells are stationary. T...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y79-016
更新日期:1979-01-01 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::The developing heart forms during the early stages of embryogenesis, and misregulated heart development results in congenital heart defects (CHDs). To understand the molecular basis of CHDs, a deep understanding of the morphological and genetic basis of heart development is necessary. Atrial Natriuretic Factor (ANF) i...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章,评审
doi:10.1139/y11-051
更新日期:2011-08-01 00:00:00
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::In this study, we aimed to investigate the protective effects of androgens, using letrozole (LET; an aromatase inhibitor), grape seed extract (GSE; a naturally occurring aromatase inhibitor and antioxidant), and testosterone propionate (Tp), against methotrexate (MTX)-induced testicular toxicity in adult male rats. MT...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-2017-0459
更新日期:2018-04-01 00:00:00
abstract::Chronic potassium deficiency in one-kidney one-clip hypertensive dogs significantly reduces blood pressure and plasma potassium, with a simultaneous increase in plasma renin activity. Tissue potassium concentration was decreased and tissue sodium concentration was increased in striated muscle and adrenal glands, which...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y83-210
更新日期:1983-12-01 00:00:00
abstract::Kinins are the endogenous ligands of the constitutive B2 receptor (B2R) and the inducible B1 receptor (B1R). Whereas B2R prevents insulin resistance, B1R is involved in insulin resistance and metabolic syndrome. However, the contribution of B1R in type 2 diabetes associated with obesity remains uncertain. The aim of t...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-2016-0063
更新日期:2016-07-01 00:00:00