Abstract:
:Negative chronotropic effects of beta-adrenoceptor (betaAR) antagonists on right atria from reserpine-treated rats and mice were determined as a test of their inverse agonist activities. BetaAR antagonist ICI-118,551 and nonselective betaAR antagonists alprenolol, propranolol, and timolol produced negative chronotropic effects. In contrast, nonselective betaAR antagonists pindolol and nadolol as well as beta1AR-selective antagonists atenolol, acebutolol, and metoprolol did not cause a significant decrease in atrial rates. The neutral antagonist pindolol but not the inverse agonist alprenolol inhibited the negative chronotropic activities of ICI-118,551. Isoprenaline, salbutamol, and noradrenaline produced positive chronotropic effects; the chronotropic effects of isoprenaline and salbutamol but not of noradrenaline were antagonized by ICI-118,551. It is concluded that both beta1AR and beta2AR mediate positive chronotropic effects of catecholamines on rat and mouse atria but only beta2AR are constitutively active.
journal_name
Can J Physiol Pharmacoljournal_title
Canadian journal of physiology and pharmacologyauthors
Varma DRsubject
Has Abstractpub_date
1999-12-01 00:00:00pages
943-9issue
12eissn
0008-4212issn
1205-7541journal_volume
77pub_type
杂志文章abstract::It was recently shown that a peptide (hypertensive factor, HF) isolated from erythrocyte hemolysates from spontaneously hypertensive rats induced a prolonged elevation of blood pressure in normotensive rats. In addition, the peptide produced a marked stimulation of the in vitro uptake of lanthanum-resistant calcium by...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y88-209
更新日期:1988-10-01 00:00:00
abstract::Hepatotoxicity and nephrotoxicity are important drawbacks of cisplatin. The objective of this study is to evaluate the ability of ambroxol in 2 different doses (35 and 70 mg/kg, i.p.) to protect liver and kidney from damage induced by a single dose of cisplatin (10 mg/kg, i.p.) in comparison with N-acetylcysteine (250...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-2018-0528
更新日期:2019-01-01 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::Extracellular spikes were recorded from cell bodies of sympathetic preganglionic neurones in spinal segments T1-T3 of the cat. Each neurone was identified by its antidromic response to electrical stimulation of the sympathetic chain and was found in histological sections to lie within the intermediolateral nucleus. Ph...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y84-198
更新日期:1984-09-01 00:00:00
abstract::Previously, we reported that thromboxane A2 (TxA2) mediates heart rate, adrenocorticotropin (ACTH), cortisol, and blood gas responses, although the specific site of action was not identified. In the present study, we interrupted vagal nervous transmission in chronically instrumented conscious sheep and infused the TxA...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-76-12-1087
更新日期:1998-12-01 00:00:00
abstract::The aim of this study was to investigate the possible effects of captopril as a promoter in modulating the oxidant-antioxidant balance in rats with type 1 diabetes, and the influence of protein kinase C (PKC) pathways in the production of reactive oxygen species (ROS) induced by bradykinin in type 1 diabetic rats. Thi...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y11-097
更新日期:2011-12-01 00:00:00
abstract::It has been proposed that the adult castrated male rat may be used as a model of human postmenopausal osteoporosis. If such a model is valid then the total body calcium of castrated rats should progressively decrease compared with normal rats. To search for this age-related difference, it will be necessary to use a me...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y85-207
更新日期:1985-10-01 00:00:00
abstract::Investigation of the relationship of diet to blood lipids and atherosclerosis has dominated the field of lipid nutritional biochemistry for the past 25 years. Although this subject has consumed considerable time, effort, and research funds, it has also proved beneficial to other areas of lipid biochemistry by attracti...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y83-040
更新日期:1983-03-01 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::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::Acetylcholine (ACh) is an important regulator of intestinal epithelial ion transport via muscarinic or nicotinic ACh receptors. Previous studies emphasize the role of the M3 muscarinic receptor subtype in mediating the effects of cholinergic agonists on intestinal ion transport. With the prevalence of mouse models to ...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y06-068
更新日期:2006-11-01 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::Atherosclerosis is a chronic inflammatory disease resulting in the formation of the atherosclerotic plaque. Plaque formation starts with the inflammation in fatty streaks and progresses through atheroma, atheromatous plaque, and fibroatheroma leading to development of stable plaque. Hypercholesterolemia, dyslipidemia,...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章,评审
doi:10.1139/cjpp-2016-0664
更新日期:2017-10-01 00:00:00
abstract::The LA/N-corpulent (LA/N-cp) rat is a normotensive strain derived from Koltesky's original mutant strain of the spontaneously hypertensive rat (SHR). When homozygous for the cp gene (cp/cp), the rats are hyperphagous, hyperlipidemic, hyperinsulinemic, and obese. The rats have been shown, by scanning electron microscop...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y86-215
更新日期:1986-10-01 00:00:00
abstract::Disposition of the bis-pyridinium mono-oxime, HI-6, following intramuscular injection in rats (200 mg/kg bw), beagle dogs (10 and 50 mg/kg bw), and rhesus monkeys (50 mg/kg bw) revealed that the oxime was absorbed rapidly and completely from the site of injection, was distributed rapidly in the tissues, and that tissu...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y90-089
更新日期:1990-05-01 00:00:00
abstract::Effects of xanthine--xanthine oxidase produced oxygen radicals were studied in hypertrophied rat hearts in a Langendorff preparation. Heart hypertrophy was produced by banding of the abdominal aorta for 6 weeks. This resulted in a 22% increase in ventricle/body weight ratio compared with that of sham-operated controls...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y87-183
更新日期:1987-06-01 00:00:00
abstract::In Western societies, the incidence of diet-related diseases is progressively increasing due to greater availability of hypercaloric food and a sedentary lifestyle. Obesity, diabetes, atherosclerosis, and neurodegeneration are major diet-related pathologies that share a common pathogenic denominator of low-grade infla...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章,评审
doi:10.1139/cjpp-2012-0307
更新日期:2013-06-01 00:00:00
abstract::The knowledge on alpha-adrenoceptors has expanded enormously in the last decade, mostly as a result of in vitro and in vivo animal experiments. In the face of considerable species differences we have tested several of the newly developed concepts on alpha-adrenoceptors in the circulation of the human forearm. In this ...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y87-258
更新日期:1987-08-01 00:00:00
abstract::NTPDase is one of the principal enzymes involved in the sequential hydrolysis of ATP. In the present study, the presence and functionality of NTPDase in the mesenteric vein and artery were examined. Adenosine triphosphate (ATP) (0.01-1000 pmol) induces a dose-dependent vasodilation in the isolated arterial and venous ...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y03-043
更新日期:2003-03-01 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::The arterio--alveolar nitrogen difference (aADN2) has been associated in 27 normal adult subjects aged 20--60 years. As it may be assumed that venous and arterial PN2 are identical, we have used a sample of venous blood. There is a significant positive correlation between aADN2 and age. As the increase of aADN2 with a...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y75-007
更新日期:1975-02-01 00:00:00
abstract::Energy-deprivation contractures were investigated in unloaded rat ventricular myocytes. Application of 2 mM cyanide in the presence of 10 mM 2-deoxyglucose (metabolic blockade) led to a rapid shortening "contracture" (maximum speed 1.5 +/- 0.2% control cell length/s). Cells shortened to a constant length of 69 +/- 1.6...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y90-029
更新日期:1990-02-01 00:00:00
abstract::A survey of 'steady-state' serum levels of anticonvulsant drugs from 221 epileptic patients at a university hospital was conducted. Serum concentrations of phenobarbital, primidone, and diphenylhydantoin were determined by a gas chromatographic method. Sixty-five percent (130) of the patients receiving diphenylhydanto...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y76-119
更新日期:1976-12-01 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::Pertussis toxin (PTX) is a heterohexameric protein, which is divided into subunits A and B. The A-subunit (protomer) possesses adenine diphosphate (ADP) ribosyltransferase activity, and the B-oligomer confers cell surface binding specificity on the toxin. By virtue of the ADP-ribosylation activity in the A-subunit, PT...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-74-5-559
更新日期:1996-05-01 00:00:00
abstract::Nitric oxide (NO) production occurs through oxidation of the amino acid L-arginine by NO synthase (NOS). NO inhibits platelet activation by increasing the levels of cyclic guanosine monophosphate (cGMP), thus maintaining vascular homeostasis. Our group previously demonstrated (da Silva et al. 2005) an enhancement of t...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y10-111
更新日期:2011-02-01 00:00:00
abstract::The guanylin family of peptides has 3 subclasses of peptides containing either 3 intramolecular disulfide bonds found in bacterial heat-stable enterotoxins (ST), or 2 disulfides observed in guanylin and uroguanylin, or a single disulfide exemplified by lymphoguanylin. These peptides bind to and activate cell-surface r...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章,评审
doi:10.1139/y11-050
更新日期:2011-08-01 00:00:00
abstract::The effect of the administration route, dose, and sampling time on the total urinary excretion of four major benzo[a]pyrene (BaP) metabolites, 3-hydroxyBaP (3-OHBaP), 9-hydroxyBaP 9-hydroxyBaP (9-OHBaP), trans-4,5-dihydrodiolBaP (4,5-diolBaP), and trans-9,10-dihydrodiolBaP (9,10-diolBaP), was studied in male Sprague-D...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-75-3-185
更新日期:1997-03-01 00:00:00
abstract::Changes in estrogen production are considered important in the sequence of events leading to parturition. We sought tissue-specific changes in the concentration of unconjugated estrone (E1) and estradiol (E2) in intrauterine fetal (amnion, chorion) and maternal (endometrium, myometrium) tissues during normal pregnancy...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y87-026
更新日期:1987-02-01 00:00:00
abstract::This study investigated the gastroprotective effects of N-acetylcysteine (NAC) against indomethacin-induced gastric ulcer in rats. Ulceration was induced by a single oral administration of indomethacin (30 mg/kg). 50 male albino rats were allocated into 5 equal groups: control group received normal saline orally, indo...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-2016-0442
更新日期:2017-04-01 00:00:00