Abstract:
:The experiment examined biological responses produced by combined sequential exposure to low-level tritium contamination, followed by challenging irradiation with fast neutrons. Modifications of endogenous antioxidant potential of different organs in rats were discussed in relation to tissue radiosensitivity. Rats pre-contaminated to 7 cGy and 35 cGy have been additionally irradiated to 1 Gy with fast neutrons. Lipid peroxide level was determined in liver, kidney, small intestine, spleen, bone marrow, and plasma. Reduced glutathione (GSH) level and glucose-6-phosphate dehydrogenase (G6PDH) activity were determined in erythrocytes. An in vitro thymidine uptake assay was performed in isolated bone marrow cells. The lipid peroxide level decreased significantly only in liver and kidney from rats pre-exposed to 35 cGy. For small intestine and spleen, tissues of comparatively higher radiosensitivity, no induced radioprotection was observed, as reflected in the homeostasis of the lipid peroxides. The same behavior was observed in bone marrow, the most radiosensitive tissue studied. However, the bone marrow thymidine-incorporation assay revealed a possible adaptive-type reaction in rats pre-exposed to 35 cGy. We conclude that for radiosensitive tissues pre-exposure to chronic low doses of low linear energy transfer (LET) irradiation has no protective effect on their antioxidant status, whereas a protective effect is observed in radioresistent tissues.
journal_name
Can J Physiol Pharmacoljournal_title
Canadian journal of physiology and pharmacologyauthors
Petcu I,Moisol N,Savu D,Constantinescu Bdoi
10.1139/y02-089subject
Has Abstractpub_date
2002-07-01 00:00:00pages
742-9issue
7eissn
0008-4212issn
1205-7541journal_volume
80pub_type
杂志文章abstract::Male spontaneously hypertensive stroke-prone (SHRsp) rats were fed 4% NaCl diets containing either 0.75% (normal) K or 2.11% (high) K, starting at 6 weeks of age. After 8 months on these diets, 40 out of 58 SHRsp rats on the 0.75% K diet had died (69% mortality) versus 2 dead out of 95 on the 2.11% K diet (2% mortalit...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y86-145
更新日期:1986-06-01 00:00:00
abstract::Idiopathic pulmonary arterial hypertension (IPAH) is a rare and devastating condition. There is no known cure for IPAH, and current treatment options are not always effective. Autologous myeloid angiogenic cells (MACs) have been explored as a novel therapy for IPAH, but preliminary data from clinical trials show limit...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-2018-0424
更新日期:2019-04-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y81-023
更新日期:1981-02-01 00:00:00
abstract::Ischemic heart disease is the leading cause of morbi-mortality in developed countries. Both ischemia-reperfusion injury and mechanisms of cardioprotection have been studied for more than 50 years. It is known that the physiopathological mechanism of myocardial ischemia involves several factors that are closely related...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章,评审
doi:10.1139/y2012-085
更新日期:2012-09-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/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/y85-144
更新日期:1985-07-01 00:00:00
abstract::The effect of varying dietary levels of zinc was evaluated in mice fed T-2 toxin. A semipurified diet was used to produce a low zinc (less than 2 parts per million (ppm], a zinc replete (100 ppm), and a high zinc (2500 ppm) diet. T-2 toxin was added to the three zinc diets at a concentration of 10 ppm. The mice were f...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y84-221
更新日期:1984-10-01 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
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y93-142
更新日期:1993-12-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y85-248
更新日期:1985-12-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y04-003
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 临床试验,杂志文章,随机对照试验
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更新日期:2002-10-01 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-76-10-11-983
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-2015-0262
更新日期:2016-09-01 00:00:00
abstract::Measurements of the presynaptic fiber volley (PSFV), the population excitatory postsynaptic potential (EPSP), and the extracellular pH in the dendritic CA1 layer of rat hippocampal slices were used to evaluate the effects of lactacidosis on central synaptic transmission. Replacement of NaCl with sodium lactate (up to ...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y90-026
更新日期:1990-02-01 00:00:00
abstract::Administration of d-fenfluramine, a serotonin-releasing drug, to male rats induced a dose-dependent increase in both serum prolactin and corticosterone concentrations. Serum growth hormone levels increased, but not significantly, at a dose of 1.25 mg/kg i.p. and decreased significantly at higher doses. When rats were ...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y87-388
更新日期:1987-12-01 00:00:00
abstract::The present study was undertaken to determine the beta-receptor subtype responsible for the enhanced anaphylactic histamine release from bovine leukocytes produced by isoprenaline. The selective beta 1 antagonist practolol competitively inhibited the enhancement of histamine release produced by isoprenaline. The selec...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y82-130
更新日期:1982-07-01 00:00:00
abstract::This study was designed to investigate whether and how triiodothyronine (T3) affects renal function in an experimental model of chronic kidney disease. Twenty-four female rats were divided into the following groups: sham-operated control group (n = 8), 5/6 nephrectomized group (Nx, n = 8), and 5/6 nephrectomized group...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-2017-0252
更新日期:2018-06-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:
更新日期:1997-12-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y94-028
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y85-125
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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::D-Serine, a recently identified gliotransmitter, serves as an endogenous coagonist binding to the glycine site of N-methyl-D-aspartate (NMDA) receptors. However, it is not clear whether this native ligand is able to bind to and modulate alpha-amino-3-hydroxyl-5-methyl-4-isoxazolepropionate (AMPA) receptors. In the pre...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y07-040
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 临床试验,杂志文章
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y95-052
更新日期:1995-03-01 00:00:00
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y84-248
更新日期:1984-12-01 00:00:00
abstract::The effects of magnesium (from 1.2 to 7.2 mM) were investigated in isolated perfused rat heart subjected to coronary artery ligation and reperfusion. Increasing magnesium concentrations, of the medium containing 3.00 mM of calcium, induced a significant bradycardia and a protective effect towards reperfusion arrhythmi...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/y90-105
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journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/Y08-033
更新日期:2008-06-01 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::This study developed an animal model of gestational obesity and prediabetes in Sprague Dawley rats using 35% sucrose supplementation (SS). Postprandially, insulin stimulates glucose uptake and nutrient partitioning via insulin-dependent as well as Hepatic Insulin Sensitizing Substance (HISS)-dependent action. HISS is ...
journal_title:Canadian journal of physiology and pharmacology
pub_type: 杂志文章
doi:10.1139/cjpp-2020-0340
更新日期:2020-10-16 00:00:00