Linked Life Data

16651463

Source:http://linkedlifedata.com/resource/pubmed/id/16651463

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2006-5-19
pubmed:abstractText
Sympathetic overactivity is implicated in the increased cardiovascular risk of cigarette smokers. Excitatory nicotinic receptors are present on peripheral chemoreceptor cells. Chemoreceptors located in the carotid and aortic bodies increase ventilation (Ve), blood pressure (BP), heart rate (HR), and sympathetic nerve activity to muscle circulation (MSNA) in response to hypoxia. We tested the hypothesis that nicotine replacement therapy (NRT) increases MSNA and chemoreceptor sensitivity to hypoxia. Sixteen young healthy smokers were included in the study (8 women). After a randomized and blinded sublingual administration of a 4-mg tablet of nicotine or placebo, we measured minute Ve, HR, mean BP, and MSNA during normoxia and 5 minutes of isocapnic hypoxia. Maximal voluntary end-expiratory apneas were performed at baseline and at the end of the fifth minute of hypoxia. Nicotine increased HR by 7+/-3 bpm, mean BP by 5+/-2 mm Hg, and MSNA by 4+/-1 bursts/min, whereas subjects breathed room air (all P<0.05). During hypoxia, nicotine also raised HR by 8+/-2 bpm, mean BP by 2+/-1 mm Hg, and MSNA by 7+/-2 bursts/min (all P<0.05). Nicotine increased MSNA during the apneas performed in normoxia and hypoxia (P<0.05). Nicotine also raised the product of systolic BP and HR, a marker of cardiac oxygen consumption, during normoxia, hypoxia, and the apneas (P<0.05). Ve, apnea duration, and O2 saturation during hypoxia and the apneas remained unaffected. In conclusion, sympathoexcitatory effects of NRT are not because of an increased chemoreflex sensitivity to hypoxia. NRT increases myocardial oxygen consumption in periods of reduced oxygen availability.
pubmed:commentsCorrections
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
1524-4563
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
47
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1162-7
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
Acute cardiovascular and sympathetic effects of nicotine replacement therapy.
pubmed:affiliation
Department of Cardiology, Erasme Hospital, Brussels, Belgium, bnajem@ulb.ac.be
pubmed:publicationType
Journal Article, Randomized Controlled Trial, Research Support, Non-U.S. Gov't