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 norepinephrine in the cardiac apex was also measured for direct comparison with [123I]MIBG uptake. One week following the induction of diabetes by streptozotocin injection (55 mg/kg, i.v.), male Sprague-Dawley rats were given subcutaneous injections of a hypertension-inducing agent, deoxycorticosterone acetate (DOCA, 25 mg/kg), or DOCA vehicle twice weekly for 3, 6, 9, or 12 weeks. At the end of each time point, the animals were injected intravenously (15 mCi/mg; 1 Ci = 37 GBq) with [123I]MIBG. The results showed a progressive decrease in MIBG uptake into the hearts of diabetic, hypertensive, and diabetic-hypertensive rats during the 12-week observation period, compared with the control group. However, length-tension papillary muscle studies at 12 weeks indicated that only the diabetic group had a diminished performance compared with control. Furthermore, an inverse relationship was observed between MIBG uptake and norepinephrine levels in the cardiac apex of the diabetic and diabetic-hypertensive groups. Therefore, we concluded that either MIBG does not provide an accurate indication of adrenergic integrity or that there is no relationship between sympathetic activity and myocardial function at the time points measured. MIBG did not prove to be a useful marker for myocardial dysfunction in diabetic rats.
journal_name
Can J Physiol Pharmacoljournal_title
Canadian journal of physiology and pharmacologyauthors
Herman LM,Dai S,Hartman NG,McNeill JHdoi
10.1139/y94-164subject
Has Abstractpub_date
1994-10-01 00:00:00pages
1162-7issue
10eissn
0008-4212issn
1205-7541journal_volume
72pub_type
杂志文章abstract：:Pathogenic mechanisms for essential hypertension are unclear despite striking efforts from numerous research teams over several decades. Increased production of reactive oxygen species (ROS) has been associated with the development of hypertension and the role of ROS in hypertension has been well documented in recent ...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章,评审
doi：10.1139/y06-077
更新日期：2006-12-01 00:00:00
abstract：:Single ventricular cells have been isolated from adult guinea pig heart using a collagenase enzyme method. The procedure is straightforward, takes about 20 min, and yields 40-65% rod-shaped cells which are quiescent in millimolar Ca2+ solution. Electrophysiological studies involving external ion changes and ionic chan...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y81-139
更新日期：1981-08-01 00:00:00
abstract：:This study examined whether the effects of FK506-binding protein dissociation from sarcoplasmic reticulum (SR) Ca(2+) release channels on excitation-contraction (EC) coupling changed when SR Ca(2+) reuptake and (or) the trans-sarcolemmal Ca(2+) extrusion were altered. The steady-state twitch Ca(2+) transient (CaT), ce...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y05-020
更新日期：2005-04-01 00:00:00
abstract：:Adult rats treated with high doses of streptozocin became progressively more hyperglycemic during the first month of the diabetic condition. Treatment of these rats with the sulfonylurea glyburide halted, and in some cases, reversed this process in a high percentage of the diabetics. Associated with the glyburide-medi...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y88-242
更新日期：1988-12-01 00:00:00
abstract：:2,4-Dinitrophenol, pentobarbital, thiopental, methoxyflurane, and halothane more often antagonized the facilitatory effects of substance P than of acetylcholine on the activity of spinal dorsal horn neurons (of unanesthetized decerebrated and spinalized cats) as well as interpeduncular and cerebral cortical cells (of ...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y78-082
更新日期：1978-06-01 00:00:00
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journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/cjpp-2019-0124
更新日期：2019-08-01 00:00:00
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journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章,评审
doi：10.1139/cjpp-2013-0486
更新日期：2014-07-01 00:00:00
abstract：:In open-chest pentothal-chloralose anesthetized dogs, plasma catecholamine and cyclic AMP levels were evaluated in the aortic and coronary sinus blood, during stimulations of the left ansa subclavia (1, 2, and 4 Hz). Basal aortic and coronary sinus catecholamine levels were respectively 0.373 +/- 0.090 and 0.259 +/- 0...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y81-080
更新日期：1981-06-01 00:00:00
abstract：:Experiments in right atria isolated from adult male rats were designed to determine which of the alpha 1-adrenergic receptor (alpha 1-AR) subtypes are involved in the positive chronotropic effect of phenylephrine, an alpha 1-AR agonist. Chloroethylclonidine (CEC), an irreversible alpha 1b-, alpha 1c-, and alpha 1d-AR ...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y94-226
更新日期：1994-12-01 00:00:00
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journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y04-011
更新日期：2004-04-01 00:00:00
abstract：:Transmural nerve stimulation following sympathetic (guanethidine 10(-4) mol/L, phenoxybenzamine 2 X 10(-5) mol/L, propanolol 2 X 10(-6) mol/L) and muscarinic blockade (atropine 5 X 10(-5) mol/L) produces a relaxatory response in canine saphenous veins contracted with prostaglandin F2 alpha. This relaxatory response wa...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y86-225
更新日期：1986-10-01 00:00:00
abstract：:The activation of mast cells (MC) due to immunological stimulation causes an immediate and dramatic inflammatory response. We review current evidence indicating that the membrane permeabilities for calcium, chloride, sodium, and potassium have a significant role in the activation of these cells, and in some cases, spe...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章,评审
doi：10.1139/y92-001
更新日期：1992-01-01 00:00:00
abstract：:The secretion of cyclic AMP, cyclic GMP, protein, calcium, and bicarbonate in the pancreatic juice of three nonanesthetized dogs with chronic gastric and duodenal Thomas cannulae has been studied. Intravenous infusions of increasing doses of cholecystokinin-pancreozymin (CCK) (1.5, 3, 6, 12, 24 Crick Harper-Raper (CHR...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y79-082
更新日期：1979-06-01 00:00:00
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journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y88-257
更新日期：1988-12-01 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：:Studies are scant on the effects of short-term carvedilol treatment as an adjuvant to angiotensin-converting enzyme (ACE) inhibitor in patients with left ventricular (LV) systolic dysfunction. The objective of this study was to find the effects of short-term treatment of carvedilol on patients with ischemic LV systoli...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章,随机对照试验
doi：10.1139/y07-006
更新日期：2007-02-01 00:00:00
abstract：:Serotonin has been shown to alter the intestinal transport of ions and intestinal motility. These effects may interfere with each other, modulating the whole physiology of the intestine. We have previously shown that serotonin also alters the transport of nutrients. Thus, the aims of the present work were to determine...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：
更新日期：2000-05-01 00:00:00
abstract：:Angiotensin exerts numerous contractile and secretory effects by activating specific receptors. Recent pharmacological findings obtained with this peptide in various laboratories are analyzed, using the order of potency of agonists and the affinity of competitive antagonists as criteria for the classification of recep...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章,评审
doi：10.1139/y79-020
更新日期：1979-02-01 00:00:00
abstract：:Lumbar spine and mid-radius bone mineral density was measured repeatedly in 48 postmenopausal women who completed 7 years of taking either a 500 mg x day(-1) calcium supplement (n = 22) or calcium supplementation with hormone replacement therapy. The hormone replacement was either a low dose (n = 15) or a moderate dos...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 临床试验,杂志文章
doi：
更新日期：1999-07-01 00:00:00
abstract：:We found when L-type calcium current (ICa-L) was recorded with the perforated patch-clamp method in rat ventricular myocytes that bath application of phenylephrine (with propranolol) evoked a biphasic response characterized by an initial transient suppression followed by a sustained potentiation. The transient suppres...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y05-058
更新日期：2005-11-01 00:00:00
abstract：:Inactivation of endothelin B receptors (ETB), either through selective pharmacological antagonism or genetic mutation, increases the circulating concentration of endothelin-1 (ET-1), suggesting ETB plays an important role in clearance of this peptide. However, the cellular site of ETB-mediated clearance has not yet be...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/Y10-041
更新日期：2010-06-01 00:00:00
abstract：:Dilated cardiomyopathy (DCM) is a multifactorial disease characterized by left ventricular dilation that is associated with systolic dysfunction and increased action potential duration. The Kir2.x K⁺ channels (encoded by KCNJ genes) regulate the inward rectifier current (IK1) contributing to the final repolarization i...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/cjpp-2012-0413
更新日期：2013-08-01 00:00:00
abstract：:A new antagonist of the vasoconstrictor eicosanoids, L-640,035, was studied in a standardized model of myocardial ischemia (MI) in anesthetized cats. This eicosanoid antagonist was not found to exert any overt hemodynamic action in cats subjected to a sham myocardial ischemia protocol. However, the antagonist markedly...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y84-246
更新日期：1984-12-01 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：:Glucagon causes marked elevations of glomerular filtration rate (GFR) in dogs when administered intravenously (i.v.) in small doses. The associated natriuresis is thought to be entirely due to increments in the filtered sodium load. In this study, renal denervation, thyroparathyroidectomy, and blockade of cholinergic,...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y75-010
更新日期：1975-02-01 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：:Smooth muscle cells exhibit phenotypic and mechanical plasticity. During maturation, signalling pathways controlling actin dynamics modulate contractile apparatus-associated gene transcription and contractile apparatus remodelling resulting from length change. Differentiated myocytes accumulate abundant caveolae that ...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章,评审
doi：10.1139/y05-107
更新日期：2005-10-01 00:00:00
abstract：:The heat production (HP), heart rate (HR), respiration rate, rumen motility, and body temperature responses to 2.5-h adrenaline (A) and noradrenaline (NA) intrajugular infusions at 0.00, 0.15, 0.30, 0.60, and 0.90 micrograms.kg-1.min-1 were studied in 10 shorn wethers which had been chronically (3-8 weeks) exposed to ...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y81-150
更新日期：1981-09-01 00:00:00
abstract：:Heparin was introduced into the stomach or duodenum of mice separately in doses of ca. 250 mg/kg. A slight anticoagulant effect in the systemic circulation was detected in whole blood clotting times and factor X inhibition. In contrast to most drugs, more heparin was absorbed from the stomach than from the intestine. ...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y76-084
更新日期：1976-08-01 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
