Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7
pubmed:dateCreated
1997-7-30
pubmed:abstractText
We investigated changes in autonomic nerve activity following caffeine intake by power spectral analysis of R-R intervals of heartbeats in humans. A beverage containing 240 mg of caffeine or a control beverage was given to 10 healthy volunteers, and R-R intervals were measured while subjects were sitting and controlling their respiration at a constant rate. After consumption of the caffeine-containing beverage, a transient and significant increase (P < 0.001) in spectral integrated values (areas under the curve) of high frequency power (high component, HC) was observed, and at 30 min the value was significantly greater than in controls (P < 0.02), suggesting an increase in vagal autonomic nerve activity. The effect of caffeine was also examined using decaffeinated coffee supplemented with exogenous caffeine (2 mg/kg body wt). A transient and significant increase (P < 0.0001) in HC was observed, and the value was significantly greater (P < 0.02) than when subjects consumed decaffeinated coffee without supplemental caffeine. The ratio of HC to total integrated value (which is also used as a selective indicator of vagal activity) was also significantly higher (P < 0.04) after caffeine consumption. Physiological variables accompanying the change in autonomic nerve activity (i.e., blood pressure, surface body temperature and heart rate) were not significantly affected by caffeine intake. These results suggest that power spectral analysis of heartbeat R-R intervals is an effective and noninvasive method for detecting subtle changes in autonomic nerve activity in response to food intake.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0022-3166
pubmed:author
pubmed:issnType
Print
pubmed:volume
127
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1422-7
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:9202101-Adult, pubmed-meshheading:9202101-Analysis of Variance, pubmed-meshheading:9202101-Area Under Curve, pubmed-meshheading:9202101-Autonomic Nervous System, pubmed-meshheading:9202101-Blood Pressure, pubmed-meshheading:9202101-Body Temperature, pubmed-meshheading:9202101-Body Temperature Regulation, pubmed-meshheading:9202101-Caffeine, pubmed-meshheading:9202101-Central Nervous System Stimulants, pubmed-meshheading:9202101-Cross-Over Studies, pubmed-meshheading:9202101-Dose-Response Relationship, Drug, pubmed-meshheading:9202101-Eating, pubmed-meshheading:9202101-Female, pubmed-meshheading:9202101-Fourier Analysis, pubmed-meshheading:9202101-Heart Rate, pubmed-meshheading:9202101-Humans, pubmed-meshheading:9202101-Male, pubmed-meshheading:9202101-Parasympathetic Nervous System, pubmed-meshheading:9202101-Sleep, pubmed-meshheading:9202101-Time Factors, pubmed-meshheading:9202101-Vagus Nerve
pubmed:year
1997
pubmed:articleTitle
Caffeine enhances modulation of parasympathetic nerve activity in humans: quantification using power spectral analysis.
pubmed:affiliation
Department of Food Science and Technology, Faculty of Agriculture, Kyoto University, Kyoto 606-01, Japan.
pubmed:publicationType
Journal Article, Clinical Trial, Randomized Controlled Trial, Research Support, Non-U.S. Gov't