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 the increase in action potential durations was greater in Purkinje strand preparations. In Purkinje strand preparations, the effect was rate dependent (i.e., the increase in duration was proportionately greater when stimulation frequency was slowed). From the concentration of each compound calculated to produce a 50% maximal increase in Purkinje fiber action potential durations, d-sotalol appeared to be one to three times more potent than either l-sotalol or the racemate. Each compound appeared to increase force development in ventricular trabecular muscle preparations stimulated at a frequency of 2 Hz. Increased force development was only observed in Purkinje strand preparations stimulated at slower rates (0.5-0.33 Hz). These results are unlike those produced by other beta-adrenergic blockers and suggest that the antiarrhythmic effects of sotalol are related primarily to its effect of action potential duration. The estimated potency ratios established for the effect of dl-sotalol and its optical isomers on both trabeculae and Purkinje fiber action potential durations (d greater than dl-l) may indicate that these effects are unrelated to the beta-adrenergic blocking properties of these compounds. The differential effect of sotalol on isolated trabeculae and Purkinje strand preparations may help to explain the clinically reported phenomenon of sotalol-induced torsade de pointes.
journal_name
Can J Physiol Pharmacoljournal_title
Canadian journal of physiology and pharmacologyauthors
Lathrop DAdoi
10.1139/y85-248subject
Has Abstractpub_date
1985-12-01 00:00:00pages
1506-12issue
12eissn
0008-4212issn
1205-7541journal_volume
63pub_type
杂志文章abstract::Slow alpha2-globulin (salpha2G), a high molecular weight glycoprotein, appears as a component of rat serum in a wide variety of both physiologic and pathologic conditions, including pregnancy; it is also present in the neonate. In the present study, the protein was detectable in serum after 6 to 10 days, and was prese...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y77-071
更新日期:1977-06-01 00:00:00
abstract::This study was conducted to examine the protective role of crude polysaccharide from brown seaweed Sargassum polycystum against acetaminophen-induced abnormality in blood glucose, serum albumin/globulin ratio, and liver glycogen, lactate, and pyruvate. Liver and renal tissue histology was performed to confirm the effi...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y08-072
更新日期:2008-10-01 00:00:00
abstract::Our studies are guided by the novel hypothesis that protein tyrosine phosphorylation is an important mechanism for regulating contraction of smooth muscle. Several lines of evidence are reviewed which suggest that enhanced tyrosine phosphorylation participates in mechanisms that regulate cytosolic Ca2+ and Ca2+ sensit...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章,评审
doi:10.1139/y94-207
更新日期:1994-11-01 00:00:00
abstract::In a porcine coronary artery helical strip preparation, the tyrosine kinase inhibitors genistein and tyrphostin (AG82) attenuated the contractile actions of angiotensin II, arginine vasopressin, epidermal growth factor--urogastrone, noradrenaline, and prostaglandin F2 alpha, under conditions where contractions due to ...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y94-150
更新日期:1994-09-01 00:00:00
abstract::In rats anesthetized with alpha-chloralose, doses of 0.1, 0.5, and 1 g/kg of ethanol produced an upward shift of baroreflex curves constructed by plotting the heart rate response against mean arterial pressure following evoked rises in mean arterial pressures by phenylephrine or angiotensin II. Whereas the upward shif...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y87-134
更新日期:1987-05-01 00:00:00
abstract::Bacterial toxins are widespread in the environment as well as in the digestive system of humans and animals. Toxin from Gram-negative bacteria (endotoxin or lipopolysaccharide; LPS) has a life-long programming effect on reproduction in rats, but the mediators have not been well-documented, so we investigated the effec...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-2014-0559
更新日期:2015-08-01 00:00:00
abstract::Total renal blood flow, glomerular filtration rate, and renal excretory function were determined in anesthetized rats treated with intravenous infusion of ethacrynic acid, 0.36 mg.min-1.kg-1, alone or in combination with cysteine. Simultaneously, the corticomedullary electrolyte gradient was evaluated in vivo from mea...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y90-191
更新日期:1990-09-01 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::Chronic caval dogs with ascites were identified as being natriuretic "responders" or "nonresponders" (delta UNaV less than 20 microequiv./min) following an infusion of atrial natriuretic peptide (ANP) (100 ng.kg-1.min-1). To learn more about the factors modulating tubular resistance to ANP, we attempted to convert res...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y92-120
更新日期:1992-06-01 00:00:00
abstract::Although chronic cocaine use is cardiotoxic, its use remains problematic in athletics. Hence adaptive changes induced in the heart by superimposing chronic cocaine use on an exercise training are of interest but remain poorly understood. Therefore this study investigated the effects of cocaine treatment combined with ...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y94-001
更新日期:1994-01-01 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::In the present study we characterized the receptor(s) that mediates non-adrenergic non-cholinergic (NANC) contractions of isolated guinea pig cervical trachea, using CP-99,994, a selective neurokinin (NK1) receptor antagonist, and SR-48,968, a selective neurokinin (NK2) receptor antagonist. The activity of these two a...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y94-028
更新日期:1994-02-01 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::Acetylcholine (ACh)-mediated vagal transmission as well as nonneuronal ACh release are considered cardioprotective in pathological situations with increased sympathetic drive such as ischemia-reperfusion and cardiac remodeling. ACh action is terminated by hydrolysis by the cholinesterases (ChEs), acetylcholinesterase,...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-2019-0565
更新日期:2020-07-01 00:00:00
abstract::The connections of area postrema include a set of nuclei with a common topographical location immediately deep to the ependyma or pia mater. These nuclei are all within two principal synapses of the area postrema and can be reached by more than one route from it. There is direct evidence that, like the area postrema, ...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章,评审
doi:10.1139/y90-039
更新日期:1990-02-01 00:00:00
abstract::Microelectrode and mechanical studies were performed with isolated guinea pig myocardium (right ventricular free walls and papillary muscles) to examine the effects of platelet-activating factor (PAF) and lysophosphatidylcholine (LPC). Low concentrations of PAF (10(-8) to 10(-6) M, a range equivalent to the blood conc...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y89-107
更新日期:1989-06-01 00:00:00
abstract::Over the past few years, a number of cases of tendon injuries associated with statin therapy have been reported. In this study, we assessed whether statins can affect the extracellular matrix (ECM) of the deep digital flexor tendon (DDFT) and patellar tendon (PT). Wistar rats were assigned to groups treated with atorv...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-2016-0133
更新日期:2017-04-01 00:00:00
abstract::Alterations in electrical conductivity between smooth muscle cells (SMCs) can alter the spread and effectiveness of electromechanical SMC contraction. We attempted to determine whether alterations in pressure-dependent constriction (PDC) occurring in relation to stroke development within the middle cerebral arteries (...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:
更新日期:1998-02-01 00:00:00
abstract::The epicardial coronary venous pressure in 16 dogs was compared with coronary arterial pressure as well as aortic, intraventricular, and intramyocardial pressures. Partial aortic occlusion augmented intraventricular (IVP), intramyocardial (IMP), aortic (AP), and coronary arterial pressures. Peripheral coronary venous ...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y83-033
更新日期:1983-03-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y75-073
更新日期:1975-08-01 00:00:00
abstract::Traumatic brain injury (TBI) is one of the main causes of intellectual and cognitive disabilities. In the clinic it is essential to limit the development of cognitive impairment after TBI. In this study, the effects of gallic acid (GA; 100 mg/kg, per oral, from 7 days before to 2 days after TBI induction) on neurologi...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-2014-0546
更新日期:2015-08-01 00:00:00
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pub_type: 临床试验,杂志文章
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更新日期:2017-06-01 00:00:00
abstract::A method for the determination of the specific activity of plasma glycerol is described. Anionic contaminants are first removed from deproteinzed plasma by anionic exchange resins (treated plasma). Glycerol in treated plasma is then quantitatively converted to glycerol-3-phosphate (G3P), which is isolated by column ch...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y82-119
更新日期:1982-06-01 00:00:00
abstract::Chronically hypoxic rats (exposed to 5000 m elevation for 3 weeks) develop pulmonary hypertension (PH) that is reversed upon return to normoxia and is blocked by bradykinin (BK) antagonist B9430 treatment (100 microg/kg s.c. three times per week). Treatment of rats with both the synthetic VEGF receptor-1/2 antagonist ...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y02-047
更新日期:2002-04-01 00:00:00
abstract::The blood volume of anesthetized rats was expanded acutely by 33% with donor blood while a caval snare was gradually tightened so that right atrial pressure (RAP) was prevented from rising (n = 6). In control experiments (n = 5) an aortic snare was used to hold mean arterial blood pressure near the values found in the...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y84-131
更新日期:1984-07-01 00:00:00
abstract::We have previously demonstrated a direct relationship between the activity of the arachidonic acid cascade in vivo and the extent of cellular damage following several types of experimental injury. Since phospholipase activity has been shown to regulate arachidonic acid availability, we tested the ability of circulatin...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y81-198
更新日期:1981-12-01 00:00:00
abstract::The influence of drugs on ciliary beat frequency in the intrapulmonary airways of rats was studied in vitro. Sympathomimetic drugs significantly increased the ciliary beat frequency. Acetylcholine, pilocarpine, aminophylline, prednisolone, potassium iodide, and ammonium chloride also caused cilioexcitation, though to ...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y75-156
更新日期:1975-12-01 00:00:00
abstract::The rat atrium contains a potent natriuretic factor which appears to inhibit the sodium reabsorption in the collecting tubules of the kidneys. We examined the effects of the injection of partially purified atrial natriuretic factor (ANF) and synthetic ANF (8-33) into rats with simultaneous infusions of dextrose or apr...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y84-105
更新日期:1984-06-01 00:00:00
abstract::Our objective was to determine the effects of a clenbuterol (CB) treatment orally administered (2 mg per kg) to rats submitted to 14 days of hindlimb unloading (HU). The morphological and the contractile properties as well as the myosin heavy chain isoforms contained in each fiber type were determined in whole soleus ...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y04-034
更新日期:2004-05-01 00:00:00
abstract::Alterations in calcium metabolism and calcium-regulating hormones have been described in essential hypertension. However, the mechanisms that mediate these responses are unknown. In previous studies, using the genetically spontaneously hypertensive rat and the mineralocorticoid-salt (DOC-salt) hypertensive rat model, ...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y95-136
更新日期:1995-07-01 00:00:00