Abstract:
WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT:Nitrates may facilitate syncope through various pathways, but the precise mechanism of nitrate-induced syncope is still under debate. The purpose of the present study was to compare the underlying haemodynamic mechanisms in subjects without and with presyncopal symptoms during a nitroglycerin-stimulated tilt-table test. WHAT THIS STUDY ADDS:A major decrease in systemic vascular resistance was documented in subjects with presyncope during 0.25 mg nitroglycerin-stimulated tilt-table test, in the absence of changes in cardiac output. These findings indicated that even a small dose of nitroglycerin significantly decreased arterial resistance and cardiac afterload. AIMS The mechanism of nitrate-induced syncope remains controversial. We examined the haemodynamic changes in healthy volunteers during nitroglycerin-stimulated tilt-table test. METHODS:Continuous radial pulse wave analysis, whole-body impedance cardiography and plethysmographic finger blood pressure were recorded in a supine position and during head-up tilt in 21 subjects with presyncopal symptoms (6 male/15 female, age 43 ± 3 years) after 0.25 mg sublingual nitroglycerin and 21 control subjects (6 male/15 female, age 43 ± 2 years). The drug was administered in the supine position and a passive head-up tilt followed 5 min later. Additionally, nitroglycerin was only administered during head-up tilt in 19 subjects and the haemodynamics were recorded. RESULTS:Supine and upright haemodynamics were similar before nitroglycerin administration in the two groups. During the nitroglycerin-stimulated tilt test, aortic and radial mean blood pressure decreased significantly more in the presyncope group when compared with the controls (P= 0.0006 and P= 0.0004, respectively). The decreases in systemic vascular resistance (P= 0.0008) and heart rate (P= 0.002), and increase in aortic reflection time (P= 0.0002) were greater in the presyncope group, while the change in cardiac index was not different between the groups (P= 0.14). If nitroglycerin was administered during the upright tilt and not in supine position, the haemodynamic changes were quite corresponding. CONCLUSIONS:Presyncopal symptoms during nitrate-stimulated tilt test were explained by decreased systemic vascular resistance and increased aortic reflection time, while cardiac output remained unchanged. These findings indicated reduced arterial resistance in nitroglycerin-induced presyncope.
journal_name
Br J Clin Pharmacoljournal_title
British journal of clinical pharmacologyauthors
Tahvanainen A,Koskela J,Leskinen M,Ilveskoski E,Nordhausen K,Kähönen M,Kööbi T,Mustonen J,Pörsti Idoi
10.1111/j.1365-2125.2010.03794.xsubject
Has Abstractpub_date
2011-01-01 00:00:00pages
41-51issue
1eissn
0306-5251issn
1365-2125journal_volume
71pub_type
杂志文章abstract:AIMS:The major objective of the present study was to investigate the effect of imatinib on the pharmacokinetics of paracetamol in patients with chronic myelogenous leukaemia (CML). METHODS:Patients (n = 12) received a single oral dose of acetaminophen 1000 mg on day 1 (control). On days 2-8, imatinib 400 mg was admini...
journal_title:British journal of clinical pharmacology
pub_type: 杂志文章
doi:10.1111/j.1365-2125.2010.03810.x
更新日期:2011-02-01 00:00:00
abstract::1 Forty-one patients with essential hypertension, stages I, II, and III, were treated with captopril alone or in combination with hydrochlorothiazide. Forty two percent were responsive to captopril alone, while the remaining 58% also required the diuretic. The need for the diuretic was related to the phase of hyperten...
journal_title:British journal of clinical pharmacology
pub_type: 杂志文章
doi:10.1111/j.1365-2125.1982.tb02065.x
更新日期:1982-01-01 00:00:00
abstract::1. Kenyan children with uncomplicated malaria given oral halofantrine (HF; non-micronised suspension; 8 mg base kg-1 body weight 6 hourly for three doses) showed wide variation in the disposition of HF and desbutylhalofantrine (HFm). 2. Eight Kenyan children with severe (prostrate) falciparum malaria who were receivin...
journal_title:British journal of clinical pharmacology
pub_type: 临床试验,杂志文章
doi:10.1111/j.1365-2125.1995.tb04450.x
更新日期:1995-03-01 00:00:00
abstract:WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT:• The CYP3A4 inhibition by lipophilic statins may attenuate the effectiveness of clopidogrel. • No studies have measured drug exposure in a time-varying manner that detects discontinuation and restart of clopidogrel and statin therapy, allowing clinical quantification of the int...
journal_title:British journal of clinical pharmacology
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doi:10.1111/j.1365-2125.2012.04169.x
更新日期:2012-07-01 00:00:00
abstract:WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT:Performance-enhancing dietary supplements have not been clinically tested for safety or efficacy. In clinical trials performed under resting conditions, performance-enhancing supplements raise blood pressure and affect glucose homeostasis. The effect of exercise on the pharmacok...
journal_title:British journal of clinical pharmacology
pub_type: 杂志文章
doi:10.1111/j.1365-2125.2008.03144.x
更新日期:2008-06-01 00:00:00
abstract:AIM:To examine comprehensively the relationship between exposure to four classes of psychotropic drugs including antipsychotics, antidepressants, benzodiazepines (BZDs) and Z-drugs, and motor vehicle accidents (MVAs). METHOD:The authors conducted a matched case-control study of 5183 subjects with MVAs and 31 093 match...
journal_title:British journal of clinical pharmacology
pub_type: 杂志文章
doi:10.1111/j.1365-2125.2012.04410.x
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abstract:AIMS:The aims of the present study were, firstly, to evaluate long-term trends in the occurrence and treatment of cardiovascular disease (CVD) risk factors and the occurrence of CVD events in children with type 1 diabetes mellitus (T1DM) and, secondly, to assess the determinants of undertreatment of CVD risk factors. ...
journal_title:British journal of clinical pharmacology
pub_type: 杂志文章
doi:10.1111/bcp.13482
更新日期:2018-04-01 00:00:00
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journal_title:British journal of clinical pharmacology
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1111/j.1365-2125.1982.tb01391.x
更新日期:1982-03-01 00:00:00
abstract::The effect of isotonic bicycle exercise on beta 2-adrenoceptors and cAMP production in lymphocytes was studied. The origin of the newly exposed receptors was studied by measuring radioligand binding in the presence of hydrophylic or lipophylic 'cold' ligands. During exercise beta 2-adrenoceptor density increased from ...
journal_title:British journal of clinical pharmacology
pub_type: 杂志文章
doi:10.1111/j.1365-2125.1990.tb05487.x
更新日期:1990-01-01 00:00:00
abstract::The binding of carbamazepine and carbamazepine 10,11-epoxide to serum, albumin and alpha 1-acid glycoprotein (AAG) was determined and compared at drug concentrations ranging from 0.5 to 400 mg/l using equilibrium dialysis and liquid chromatography. The total binding of carbamazepine in serum was determined primarily b...
journal_title:British journal of clinical pharmacology
pub_type: 杂志文章
doi:10.1111/j.1365-2125.1984.tb02496.x
更新日期:1984-10-01 00:00:00
abstract::1. Azole antifungal agents such as ketoconazole act by inhibiting cytochrome P-450 mediated sterol synthesis in the fungal cell membrane and thus have the potential to interfere with mammalian steroidogenesis. Fluconazole is a novel orally-effective antifungal triazole which has been reported to have more specific eff...
journal_title:British journal of clinical pharmacology
pub_type: 临床试验,杂志文章
doi:10.1111/j.1365-2125.1989.tb03449.x
更新日期:1989-06-01 00:00:00
abstract::1 A double-blind trial with parallel treatment groups was conducted to compare the safety and efficacy of mianserin with amitriptyline. 2 This was a six week trial with weekly visits. Measurements at each visit included: 21 item Hamilton Depression (HAMD) Scale. Clinical Global Impression (CGI) Scale and Treatment Eme...
journal_title:British journal of clinical pharmacology
pub_type: 临床试验,杂志文章
doi:10.1111/j.1365-2125.1983.tb05870.x
更新日期:1983-01-01 00:00:00
abstract:AIMS:To evaluate the role of reported daily dose, age and other risk factors, and to assess the value of quantifying serum transaminase activity and paracetamol (acetaminophen) concentration at initial assessment for identifying patients at risk of hepatotoxicity following repeated supratherapeutic paracetamol ingestio...
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更新日期:2016-10-01 00:00:00
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doi:10.1046/j.0306-5251.2001.01518.x
更新日期:2002-01-01 00:00:00
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更新日期:2020-07-08 00:00:00
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doi:10.1111/j.1365-2125.1997.tb00030.x
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doi:10.1111/j.1365-2125.2012.04285.x
更新日期:2012-11-01 00:00:00
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journal_title:British journal of clinical pharmacology
pub_type: 杂志文章
doi:10.1111/j.1365-2125.1980.tb01811.x
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pub_type: 临床试验,杂志文章,多中心研究
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doi:10.1111/j.1365-2125.1983.tb02139.x
更新日期:1983-07-01 00:00:00
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journal_title:British journal of clinical pharmacology
pub_type: 杂志文章,多中心研究
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更新日期:2006-02-01 00:00:00
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journal_title:British journal of clinical pharmacology
pub_type: 临床试验,杂志文章
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更新日期:1997-07-01 00:00:00
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pub_type: 杂志文章,评审
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更新日期:2014-04-01 00:00:00
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journal_title:British journal of clinical pharmacology
pub_type: 杂志文章
doi:10.1046/j.1365-2125.1998.00793.x
更新日期:1998-10-01 00:00:00
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journal_title:British journal of clinical pharmacology
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更新日期:1983-04-01 00:00:00
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pub_type: 临床试验,杂志文章
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更新日期:2004-03-01 00:00:00
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journal_title:British journal of clinical 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:1990-03-01 00:00:00
abstract::1. The aromatic 2-hydroxylation of imipramine was studied in microsomes from three human livers. The kinetics were best described by a biphasic enzyme model. The estimated values of Vmax and Km for the high affinity site ranged from 3.2 to 5.7 nmol mg-1 h-1 and from 25 to 31 microM, respectively. 2. Quinidine was a po...
journal_title:British journal of clinical pharmacology
pub_type: 杂志文章
doi:10.1111/j.1365-2125.1992.tb04133.x
更新日期:1992-09-01 00:00:00
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journal_title:British journal of clinical pharmacology
pub_type: 临床试验,杂志文章
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更新日期:2000-08-01 00:00:00
abstract::Ethanol aggravates benzodiazepine-induced central nervous depression by pharmacokinetic and/or pharmacodynamic interactions and Ro 15-1788 reverses promptly the hypnotic effects of benzodiazepines. We therefore studied the acute effects of Ro 15-1788 on the ethanol-induced sedation in six healthy male subjects. Subseq...
journal_title:British journal of clinical 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:1986-11-01 00:00:00