Abstract：
:A principal step in the process leading to muscle contraction is the intracellular release of Ca2+. We have detected and compared some physical and chemical events that reflect Ca2+ release in contracting frog skeletal muscle cells, described the effects of some agents that are believed to alter intracellular Ca2+ release during contraction, and speculated about the role of Ca2+ release in influencing some of the mechanical properties of frog muscle. The specific physical features recorded were changes in striation spacing, myofibrillar orientation, and force development. The chemical feature was the relative change in intracellular [Ca2+] recorded as light emission from cells microinjected with the Ca2+-sensitive protein aequorin. The presence or absence of a correlation among these variables has been used (i) to evaluate the action of some agents thought to change intracellular Ca2+ release in excitation--contraction (E--C) coupling, (ii) to further substantiate the effects of cell length on Ca2+ release, and (iii) to examine some details of models for E--C coupling. The results showed that potentiating agents enhance and prolong intracellular Ca2+ release without changing the rate of Ca2+ removal during E--C coupling. This extra Ca2+ does not produce the same effect on contractions at all lengths. Contractility is inversely related to cell length, and Ca2+-induced activation is normally less than maximum not only at short lengths but also at optimal striation spacings.
journal_name
Can J Physiol Pharmacoljournal_title
Canadian journal of physiology and pharmacologyauthors
Taylor SR,Lopez JR,Griffiths PJ,Trube G,Cecchi Gdoi
10.1139/y82-068subject
Has Abstractpub_date
1982-04-01 00:00:00pages
489-502issue
4eissn
0008-4212issn
1205-7541journal_volume
60pub_type
杂志文章abstract：:When isolated rat adipocytes were incubated with increasing concentrations of levamisole (0.5-5 mM), basal glucose oxidation decreased by almost 50% and insulin-stimulated glucose oxidation decreased by 90%. The decrease in glucose oxidation correlated with an inhibition of glucose transport, since levamisole at 5.0 m...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y92-165
更新日期：1992-08-01 00:00:00
abstract：:The aim of the present investigation was to elucidate the pharmacological mechanism by which U44069, a stable PGH2 analogue, contracts the rat aorta. The results obtained demonstrate that while the contractile effect of potassium chloride is obliterated by removal of extracellular calcium, a substantial proportion of ...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y82-103
更新日期：1982-05-01 00:00:00
abstract：:The effects of acute hypercapnia on human thermoregulation during cold exposure were investigated by immersion of eight male subjects to the neck in a 15 degrees C water bath until their core temperatures dropped to 35 degrees C or until 1 h of immersion had elapsed. Air was inspired throughout each experiment, with t...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 临床试验,杂志文章
doi：10.1139/y94-037
更新日期：1994-03-01 00:00:00
abstract：:Existing literature provides an equivocal picture of the behavior of mitochondrial synthesis during the time course of cardiac hypertrophy. Therefore, we examined the effect of cardiac hypertrophy on mitochondrial cytochrome c oxidase (CYTOX) activity, the content of CYTOX subunit VIc mRNA, and the expression of molec...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y95-080
更新日期：1995-05-01 00:00:00
abstract：:The pharmacological characteristics of postjunctional alpha-adrenoceptors in isolated canine internal carotid arteries were investigated by the use of selective agonists and antagonists for alpha 1- and alpha 2-adrenoceptors. Norepinephrine, phenylephrine, and xylazine caused concentration-dependent contractions in th...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y88-102
更新日期：1988-05-01 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 role of leukotriene D4 (LTD4) as a mediator of immediate hypersensitivity reactions in the guinea-pig conjunctiva was examined using a potent, second-generation LTD4 receptor antagonist, MK-571 (also known as L-660,711). The microvascular permeability changes in the guinea-pig conjunctiva following challenge with ...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y89-132
更新日期：1989-08-01 00:00:00
abstract：:Theanine and caffeine, 2 naturally occurring components in tea, have repeatedly been shown to deliver unique cognitive benefits when consumed in combination. In this study, we assessed the beneficial synergistic effects of concurrent treatment with theanine and caffeine against cerebral damage in rats. Theanine and ca...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/cjpp-2012-0309
更新日期：2013-07-01 00:00:00
abstract：:The isolated human vas deferens (HVD) has been the subject of a limited number of pharmacological studies. Furthermore, it has not been established whether the local or general anesthetics used in obtaining the HVD affect the responses of this isolated tissue. Therefore, the aim of this study was to determine if the l...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y86-075
更新日期：1986-04-01 00:00:00
abstract：:Hyperglycemia in diabetes induces increased endothelin-1 (ET-1) production in the retina, kidney, and heart that may lead to hemodynamic impairment, permeability alteration, and increased extracellular matrix (ECM) protein production. Chronically elevated blood glucose levels may cause oxidative stress in these target...
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：:Our previous studies have suggested that GATA-4 increases the differentiation of bone-marrow-derived mesenchymal stem cells (MSCs) into cardiac phenotypes. This study further investigated whether GATA-4 enhances MSC-mediated cardioprotection following hypoxia. MSCs were harvested from rat bone marrow and transduced wi...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/cjpp-2014-0009
更新日期：2014-08-01 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：:The long noncoding RNA (lncRNA) GAS5 has been found to act as a decoy for the glucocorticoid receptor (GR), thus implicating GAS5 as a potential regulator of glucocorticoid sensitivity and resistance. Airway smooth muscle (ASM) cells and airway epithelial cells (AEC) play an important role in the pathogenesis and pers...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/cjpp-2014-0391
更新日期：2015-03-01 00:00:00
abstract：:Changes in metabolic characteristics of the liver and jejunal epithelia as a result of feeding the beta-agonist albuterol to chickens for 3 and 6 weeks were studied. Feeding albuterol resulted in a change in weights of the liver and small intestines. Chickens fed albuterol for 6 weeks had greater levels of plasma none...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y89-069
更新日期：1989-05-01 00:00:00
abstract：:Intrinsic regulation of hepatic blood flow is mediated only through the hepatic artery because the liver is not able to directly regulate portal vein blood flow. Hepatic metabolic activity does not affect hepatic artery flow. Although the hepatic artery is affected by sympathetic nerves and blood-borne agents, the int...
journal_title：Canadian journal of physiology and pharmacology
pub_type：
doi：
更新日期：1996-03-01 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：:Neuronal factors co-released with neurotransmitters may play an important role in synapse development and function. Calcitonin gene related peptide (CGRP) and adenosine 5'-triphosphate (ATP), two principal neuromodulators present in the motor nerve terminals, were studied for their roles and mechanisms during early de...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章,评审
doi：10.1139/y95-149
更新日期：1995-07-01 00:00:00
abstract：:Lesion to the posterior parietal cortex in monkeys and humans produces spatial deficits in movement and perception. In recording experiments from area 7a, a cortical subdivision in the posterior parietal cortex in monkeys, we have found neurons whose responses are a function of both the retinal location of visual stim...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y88-078
更新日期：1988-04-01 00:00:00
abstract：:The mammalian daily (circadian) clock is located in the suprachiasmatic nuclei of the hypothalamus. Clock function can be detected by the measurement of the circadian change in spontaneous firing rate of suprachiasmatic nuclei cells in a brain slice preparation in vitro. We investigated the effects of neuropeptide Y o...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：
更新日期：2000-02-01 00:00:00
abstract：:Chrysin (CH) is a natural flavonoid with pharmacological influences. The purpose of the current study was the assessment of possible protective effects of CH against oxidative damage in the serum, liver, brain, and pancreas of streptozotocin (STZ)- induced diabetic rats. In the present study, the rats were divided int...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/cjpp-2014-0412
更新日期：2016-04-01 00:00:00
abstract：:We investigated the effects of 4% fructose plus moderately high salt (MHS) (4% NaCl) treatment on tissue aldehyde conjugates, platelet cytosolic free calcium ([Ca2+]i), renal morphology, and systolic blood pressure (SBP) in Wistar-Kyoto rats, and whether these effects were reversible (R) after withdrawal of treatment....
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y06-080
更新日期：2007-03-01 00:00:00
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journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y09-008
更新日期：2009-05-01 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-2014-0118
更新日期：2015-01-01 00:00:00
abstract：:The role of I(K) (delayed rectifier current) and I(f) (hyperpolarization-activated current) in dominant and subsidiary pacemaker ranges was studied in single myocytes isolated from the guinea pig sino-atrial node by means of a perforated patch-clamp technique. In the dominant pacemaker range (approx. -55 to -40 mV), I...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：
更新日期：2001-12-01 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：:Xerostomia is a self-conscious symptom. High-mobility group box 1 (HMGB1) promotes pro-inflammatory effects in many diseases. This study aimed to clarify the role of HMGB1 in Sjögren syndrome (SS)-triggered xerostomia. Nonobese diabetic (NOD)/Ltj mice were used to establish an SS-triggered xerostomia model. The result...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/cjpp-2019-0337
更新日期：2020-06-01 00:00:00
abstract：:Acute administration of morphine sulfate at 20 mg/kg decreased mouse cerebellar adenosine 3',5'-cyclic phosphate (cAMP) levels while not affecting cAMP phosphodiesterase (EC 3.1.4.17). The cAMP levels and cAMP phosphodiesterase activies were not affected by chronic treatment. However, cAMP levels increased during abru...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y77-017
更新日期：1977-02-01 00:00:00
abstract：:The endothelin receptors in rabbit isolated rings of saphenous artery and saphenous vein have been characterized using endothelin-1, endothelin-2, endothelin-3, sarafotoxin S6c, and BQ123. Although artery rings were more sensitive than those from vein to the contractile action of phenylephrine, endothelin-1 was about ...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y93-122
更新日期：1993-10-01 00:00:00
abstract：:In recent years a considerable amount of experimental evidence has suggested that forebrain structures are involved in the pathogenesis of high arterial pressure (AP). However, little is known about the location and function of these supramedullary structures in the hypertensive process. This report reviews a series o...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/y87-248
更新日期：1987-08-01 00:00:00
abstract：:Diazinon (DZN) is a common organophosphorus insecticide extensively used for agriculture and veterinary purposes. DZN toxicity is not limited to insects; it also induces harmful effects in mammals and birds. Our experiment evaluated the protective and antioxidant potential of sesame oil (SO) and (or) alpha-lipoic acid...
journal_title：Canadian journal of physiology and pharmacology
pub_type： 杂志文章
doi：10.1139/cjpp-2015-0131
更新日期：2016-01-01 00:00:00
