Abstract:
:We studied the effects of Zn2+ and Cd2+ on the behaviour of IK(f), a transient outward potassium current in acutely dissociated melanotrophs of the pars intermedia of the rat pituitary gland. Micromolar concentrations of external Cd2+ or Zn2+ caused parallel and nearly equal rightward shifts along the voltage axis of the activation and steady-state inactivation curves for IK(f). The KD for the half-maximal shift of the activation curve was 278 microM for Cd2+ and 93 microM for Zn2+; the maximal shifts of the activation curve were 32.5 and 34 mV, for Cd2+ and Zn2+, respectively. The times to half-activation and half-inactivation were shifted rightward by 30-60 mV in both 500 microM Cd2+ and 500 microM Zn2+. We suggest that Cd2+ and Zn2+ interact specifically with a binding site on or electrically close to the IK(f) channel and in so doing modify the electric field "seen" by the voltage sensors.
journal_name
Can J Physiol Pharmacoljournal_title
Canadian journal of physiology and pharmacologyauthors
Davidson JL,Kehl SJdoi
10.1139/y95-005subject
Has Abstractpub_date
1995-01-01 00:00:00pages
36-42issue
1eissn
0008-4212issn
1205-7541journal_volume
73pub_type
杂志文章abstract::Small, sinusoidal length changes were superimposed on isometric contractions of fast- and slow-twitch mouse muscles, which were stimulated maximally via their nerves. Stiffness increased with increasing frequency of sinusoidal stimulation, but the relative time course of force and stiffness changes during twitch, teta...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y86-209
更新日期:1986-09-01 00:00:00
abstract::We tested the hypothesis that ethanol consumption would aggravate the renal damage induced by cyclophosphamide (CYP). Male C57BL/6J mice from control (n=8) and CYP (n=12) groups had free access to filtered water and standard rodent chow for 12 weeks. Then, 24 h before euthanasia mice received an intraperitoneal inject...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-2020-0246
更新日期:2020-11-11 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 threshold for electrically induced ventricular fibrillation was determined in anesthetized open-chest dogs, before and after blockade of atrioventricular (A-V) conduction. Without exception, the threshold was significantly elevated after creation of the block. The precise mechanism of this effect is not known at t...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y83-160
更新日期:1983-09-01 00:00:00
abstract::Beneficial effects of an antioxidant (N-acetyl-L-cysteine, NAC) and an angiotensin I-converting enzyme (ACE) inhibitor (ramipril) were assessed in a rat model of insulin resistance induced by 10% glucose feeding for 20 weeks. Treatments with NAC (2 g/kg per day) and ramipril (1 mg/kg per day) were initiated at 16 week...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/Y08-090
更新日期:2008-11-01 00:00:00
abstract::Using the glycogen depletion technique, we have examined utilization of specific fibre types during prolonged submaximal exercise to investigate the recruitment pattern employed by the central nervous system to sustain force generation in the face of a progressive glycogen depletion. Six male subjects (Vo2 max, 52.8 +...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y90-208
更新日期:1990-10-01 00:00:00
abstract::Gripp-Heel is a homeopathic preparation frequently used in the treatment of respiratory viral infections such as various types of influenza and the common cold. The antiviral activity of Gripp-Heel was studied in vitro on human pathogenic enveloped and nonenveloped RNA and DNA viruses. Before the antiviral assays, in ...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/Y07-100
更新日期:2007-11-01 00:00:00
abstract::To clarify the beneficial effects of cilnidipine, an L- and N-type calcium channel blocker, which were clinically observed against diastolic dysfunction in hypertrophied hearts of hypertensive patients, we investigated the effects of cilnidipine on cardiac remodeling and enhanced gene expression in stroke-prone, spont...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y05-067
更新日期:2005-08-01 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::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::The hypocalcaemic action of ethanol (3 g/kg body weight) was investigated in intact, thyroparathyroidectomized and antrectomized rats. It was found that ethanol administered either intraperitoneally or orally reduced plasma calcium concentrations within 30 min and that this response lasted for 8 h. Additional studies ...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y83-059
更新日期:1983-04-01 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::The pHi regulation from intracellular acidosis in the central nervous system appears to be mediated by mechanisms driven by the large inwardly directed Na+ gradient. The involvement of these mechanisms in pHi regulation of neurones and glial cells has been investigated in the leech central nervous system using ion-sel...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y92-273
更新日期:1992-01-01 00:00:00
abstract::Isolated rabbit hearts undergo ventricular depolarization when exposed to 0.5 mM K--Krebs during 30 to 45 min. A ventricular tachyarrhythmia develops when these hearts are allowed to repolarize in 1.5 mM K--Krebs. Ventricular fibrillation usually follows. These arrhythmias do not cease spontaneously. Initially, perfus...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y82-226
更新日期:1982-12-01 00:00:00
abstract::The relationship between the postsynaptic alpha 1-adrenoceptor reserve and the sensitivity of vasoconstriction induced by alpha-adrenoceptor agonists to the dihydropyridine Ca2+ entry blocker nifedipine was investigated in isolated muscle strips of dog mesenteric artery (DMA) and saphenous vein (DSV). The amplitudes o...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y90-203
更新日期:1990-10-01 00:00:00
abstract::Initially the impetus to develop iron (Fe) chelators for clinical use was based upon the need for a drug to treat Fe-overload diseases such as beta-thalassemia. However, it has become clear that Fe chelators may be useful for the treatment of a wide variety of disease states, including cancer, malaria, and free radica...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章,评审
doi:
更新日期:1997-10-01 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::An investigation was made of the radiosensitivity of the toxic and immunological properties of Androctonus australis hector venom. This venom was irradiated with two doses of gamma rays (1 and 2 kGy) from a 60Co source. The results showed that venom toxicity was abolished for the two radiation doses (1 and 2 kGy) with...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y03-115
更新日期:2003-12-01 00:00:00
abstract::This study evaluated the in vitro expression of bone-related proteins by osteoblasts in the presence of different concentrations of human recombinant bone morphogenetic protein-2 (rhBMP-2). Immortalized human fetal osteoblastic cell line 1.19 (hFOB) were exposed to different concentrations of rhBMP-2 (10, 50, or 100 n...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-2013-0080
更新日期:2013-11-01 00:00:00
abstract::We used the clearance ratio test to determine whether the presence of albumin enhances the uptake of palmitate by hepatocyte monolayers. If uptake is facilitated, then the ratio of palmitate clearance by hepatocytes in the presence of 600 and 300 microM albumin (i.e., Clt600/Clt300) will exceed the square root of the ...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y93-130
更新日期:1993-12-01 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::Alterations of the ionic constituents of solutions perfused through the tissue of the posterior hypothalamic region in conscious cats elicited changes in body temperatures. Increasing the (Ca2+) to (Na+) ratio of the perfusion solution elicited falls in body temperature which were accompanied by changes in posture and...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y78-091
更新日期:1978-08-01 00:00:00
abstract::One hypothesized mechanism of the cardioprotection provided by preconditioning is decreased utilization of ATP during ischemia. Although ATP levels in preconditioned heart during ischemia have been previously studied, contractile activity during ischemia has not been investigated. Contractile activity accounts for sig...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:
更新日期:1997-04-01 00:00:00
abstract::Significant tension development resulting from the administration of lanthanum salts (La3+) to isolated aorta tissues was observed in preparations from the spontaneously hypertensive rat (SHR) but not in preparation from age-matched normotensive Wistar rats (NWR). The response to La3+ was significantly greater in tiss...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y77-148
更新日期:1977-10-01 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 aim of this study was to demonstrate that within a population of healthy men (n = 15) of varying levels of aerobic fitness (VO2max = 36-74 mL.kg-1.min-1), (i) there are high and low responders with respect to carotid-cardiac baroreflex responsiveness, despite similar baseline heart rates (HRs) both at rest and dur...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 临床试验,杂志文章
doi:10.1139/y95-014
更新日期:1995-01-01 00:00:00
abstract::Previous studies have demonstrated that abdominal irradiation alters intestinal uptake of nutrients. The purpose of this study was to determine the effect of an orally administered synthetic prostaglandin E2, enprostil, given on three occasions shortly prior to a single exposure to 600 cGy external abdominal irradiati...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y89-215
更新日期:1989-10-01 00:00:00
abstract::In 2-kidney, 1-clip hypertensive rats, the time course of changes in blood pressure (BP), heart rate, activity of the sympathetic nervous system and the renin-angiotensin system, plasma and blood volumes, left ventricular (LV) and right ventricular (RV) weight, and LV dimensions were evaluated during treatment with hy...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y86-257
更新日期:1986-12-01 00:00:00
abstract::We hypothesized that the respiratory baroreflex in conscious rats is either more transient, or has a higher pressure threshold than in other species. To characterize the effect of arterial pressure changes on respiration in conscious rats, ventilation (V) was measured by the plethysmographic technique during injection...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-76-7-8-707
更新日期:1998-07-01 00:00:00
abstract::The interactions of ligands with their receptors and the modulation of those interactions by other ligands are commonly described in the (verbal and mathematical) language of enzymology. While this analogy is appropriate in that velocity-substrate concentration curves and ligand-receptor binding isotherms often confor...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y88-059
更新日期:1988-04-01 00:00:00