Abstract:
:Electrical field stimulation (EFS, 2.5 Hz, 60 V, 1 ms, trains of 5 sec every 5 min) of the rat external urethral sphincter (EUS) produced contractile responses characterized by a "slow" tonic contraction on which was superimposed a series of phasic "twitch-like" contractions. Both responses were abolished by tetrodotoxin (0.6 microM), and their amplitude was significantly lower in samples taken from denervated (15 days before) sphincters. The tonic contraction showed duration, voltage, and frequency dependency, whereas the twitches were markedly duration dependent. No correlation was found between the amplitude of the tonic and that of the twitch-like contractions. Phentolamine (3 microM) reduced by 95% the amplitude of the tonic contraction produced by maximal parameters, whereas it did not affect the twitches. On the other hand, hexamethonium (10 microM) was ineffective on both components. Dantrolene (10 microM) inhibited the twitch response, whereas it did not influence the tonic component. Preincubation with d-tubocurarine (0.2 mM) or succinylcholine (2 mM) significantly inhibited the amplitude of twitches produced by EFS (0.1 Hz, 60 V) up to a duration of 50 microseconds. Stimulus width higher than 50 microseconds, resulted in twitches that were resistant to neuromuscular blocking agents but sensitive to dantrolene (10 microM). Our results indicate that the rat external urethral sphincter is a reliable and easy "in vitro" model for studying the activity of drugs capable of interfering with the nerve-mediated activity of the striated and smooth muscle portion of the urinary bladder outlet.
journal_name
J Pharmacol Toxicol Methodsjournal_title
Journal of pharmacological and toxicological methodsauthors
Parlani M,Manzini S,Argentino-Storino A,Conte Bdoi
10.1016/1056-8719(92)90052-3keywords:
subject
Has Abstractpub_date
1992-09-01 00:00:00pages
85-90issue
2eissn
1056-8719issn
1873-488Xpii
1056-8719(92)90052-3journal_volume
28pub_type
杂志文章abstract::The clinical value of coronary vasodilators in antianginal therapy depends on the ratio of their epicardial versus resistance coronary vessel actions. The coronary flow measured in standard isolated heart preparations, however, does not allow any conclusion about the function of epicardial vessels. Thus, we establishe...
journal_title:Journal of pharmacological and toxicological methods
pub_type: 杂志文章
doi:10.1016/s1056-8719(97)00096-8
更新日期:1997-12-01 00:00:00
abstract:INTRODUCTION:Reversible protein cysteine oxidation is recognised as a pivotal post-transitional modification that transduces physiological as well as pathological signalling. Pharmacological interventions that target specific sources of oxidant formation are currently being trialled to ascertain their potential ability...
journal_title:Journal of pharmacological and toxicological methods
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更新日期:2013-11-01 00:00:00
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journal_title:Journal of pharmacological and toxicological methods
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journal_title:Journal of pharmacological and toxicological methods
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doi:10.1016/j.vascn.2009.02.005
更新日期:2009-05-01 00:00:00
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journal_title:Journal of pharmacological and toxicological methods
pub_type: 杂志文章
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journal_title:Journal of pharmacological and toxicological methods
pub_type: 杂志文章
doi:10.1016/j.vascn.2007.05.002
更新日期:2007-09-01 00:00:00
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journal_title:Journal of pharmacological and toxicological methods
pub_type: 杂志文章
doi:10.1016/s1056-8719(97)00066-x
更新日期:1997-10-01 00:00:00
abstract:INTRODUCTION:The purpose of this study was to optimize carbon tetrachloride-induced hepatotoxicity in the rat with respect to dose, route of injection, and time course. METHODS:Male Wistar albino rats, 4 to 6 weeks old and weighing 130-180 g were used. Hepatotoxicity was evaluated by measuring the activity of serum en...
journal_title:Journal of pharmacological and toxicological methods
pub_type: 杂志文章
doi:10.1016/S1056-8719(03)00019-4
更新日期:2002-07-01 00:00:00
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journal_title:Journal of pharmacological and toxicological methods
pub_type: 杂志文章
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更新日期:2000-05-01 00:00:00
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journal_title:Journal of pharmacological and toxicological methods
pub_type: 杂志文章
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更新日期:2005-11-01 00:00:00
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journal_title:Journal of pharmacological and toxicological methods
pub_type: 杂志文章
doi:10.1016/j.vascn.2011.08.005
更新日期:2011-11-01 00:00:00
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journal_title:Journal of pharmacological and toxicological methods
pub_type: 杂志文章
doi:10.1016/j.vascn.2010.04.004
更新日期:2010-07-01 00:00:00
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journal_title:Journal of pharmacological and toxicological methods
pub_type: 杂志文章
doi:10.1016/j.vascn.2014.11.002
更新日期:2015-01-01 00:00:00
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journal_title:Journal of pharmacological and toxicological methods
pub_type: 杂志文章
doi:10.1016/j.vascn.2005.02.003
更新日期:2006-01-01 00:00:00
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journal_title:Journal of pharmacological and toxicological methods
pub_type: 杂志文章
doi:10.1016/j.vascn.2004.08.012
更新日期:2005-05-01 00:00:00
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journal_title:Journal of pharmacological and toxicological methods
pub_type: 杂志文章
doi:10.1016/j.vascn.2008.03.001
更新日期:2008-05-01 00:00:00
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journal_title:Journal of pharmacological and toxicological methods
pub_type: 杂志文章
doi:10.1016/s1056-8719(02)00219-8
更新日期:2002-03-01 00:00:00
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journal_title:Journal of pharmacological and toxicological methods
pub_type: 杂志文章
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更新日期:2020-09-01 00:00:00
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journal_title:Journal of pharmacological and toxicological methods
pub_type: 杂志文章
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journal_title:Journal of pharmacological and toxicological methods
pub_type: 杂志文章
doi:10.1016/j.vascn.2012.10.005
更新日期:2013-01-01 00:00:00
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journal_title:Journal of pharmacological and toxicological methods
pub_type: 杂志文章
doi:10.1016/j.vascn.2015.05.002
更新日期:2015-09-01 00:00:00
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journal_title:Journal of pharmacological and toxicological methods
pub_type: 杂志文章
doi:10.1016/1056-8719(94)90008-6
更新日期:1994-08-01 00:00:00
abstract:INTRODUCTION:A Tecan-based enzyme inhibition assay has been developed for the determination of atorvastatin-derived 'active' and 'total' (active inhibitors plus atorvastatin lactone and other potential inhibitors following base hydrolysis) 3-hydroxy-3-methylglutaryl-Coenzyme A (HMG-CoA) reductase inhibitor concentratio...
journal_title:Journal of pharmacological and toxicological methods
pub_type: 杂志文章
doi:10.1016/j.vascn.2007.06.002
更新日期:2008-01-01 00:00:00
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journal_title:Journal of pharmacological and toxicological methods
pub_type: 杂志文章
doi:10.1016/s1056-8719(98)00012-4
更新日期:1998-03-01 00:00:00
abstract:INTRODUCTION:The ability to quantify systemic concentrations of protein therapeutics is complicated by the presence of endogenous analyte, specific binding proteins, and nonspecific matrix components in biological matrices (Lee & Ma, 2007). Further complications can be introduced following pegylation whereby polyethyle...
journal_title:Journal of pharmacological and toxicological methods
pub_type: 杂志文章
doi:10.1016/j.vascn.2009.12.004
更新日期:2010-03-01 00:00:00
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journal_title:Journal of pharmacological and toxicological methods
pub_type: 杂志文章
doi:10.1016/j.vascn.2010.04.001
更新日期:2011-01-01 00:00:00
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journal_title:Journal of pharmacological and toxicological methods
pub_type: 杂志文章,评审
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更新日期:2018-01-01 00:00:00
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journal_title:Journal of pharmacological and toxicological methods
pub_type: 杂志文章
doi:10.1016/j.vascn.2019.01.002
更新日期:2019-01-01 00:00:00
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journal_title:Journal of pharmacological and toxicological methods
pub_type: 杂志文章,评审
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更新日期:1997-09-01 00:00:00
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journal_title:Journal of pharmacological and toxicological methods
pub_type: 杂志文章,评审
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更新日期:1994-02-01 00:00:00