| Blood flow to contracting human muscles: influence of increased sympathetic activity. | |
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MedLine Citation:
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PMID: 2347787 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
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The purpose of this study was to examine the effects of the increased sympathetic activity elicited by the upright posture on blood flow to exercising human forearm muscles. Six subjects performed light and heavy rhythmic forearm exercise. Trials were conducted with the subjects supine and standing. Forearm blood flow (FBF, plethysmography) and skin blood flow (laser Doppler) were measured during brief pauses in the contractions. Arterial blood pressure and heart rate were also measured. During the first 6 min of light exercise, blood flow was similar in the supine and standing positions (approximately 15 ml.min-1.100 ml-1); from minutes 7 to 20 FBF was approximately 3-7 ml.min-1.100 ml-1 less in the standing position (P less than 0.05). When 5 min of heavy exercise immediately followed the light exercise, FBF was approximately 30-35 ml.min-1.100 ml-1 in the supine position. These values were approximately 8-12 ml.min-1.100 ml-1 greater than those observed in the upright position (P less than 0.05). When light exercise did not precede 8 min of heavy exercise, the blood flow at the end of minute 1 was similar in the supine and standing positions but was approximately 6-9 ml.min-1.100 ml-1 lower in the standing position during minutes 2-8. Heart rate was always approximately 10-20 beats higher in the upright position (P less than 0.05). Forearm skin blood flow and mean arterial pressure were similar in the two positions, indicating that the changes in FBF resulted from differences in the caliber of the resistance vessels in the forearm muscles.(ABSTRACT TRUNCATED AT 250 WORDS) |
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Authors:
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M J Joyner; R L Lennon; D J Wedel; S H Rose; J T Shepherd |
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Publication Detail:
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Type: Journal Article; Research Support, Non-U.S. Gov't; Research Support, U.S. Gov't, P.H.S. |
Journal Detail:
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Title: Journal of applied physiology (Bethesda, Md. : 1985) Volume: 68 ISSN: 8750-7587 ISO Abbreviation: J. Appl. Physiol. Publication Date: 1990 Apr |
Date Detail:
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Created Date: 1990-07-11 Completed Date: 1990-07-11 Revised Date: 2007-11-14 |
Medline Journal Info:
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Nlm Unique ID: 8502536 Medline TA: J Appl Physiol Country: UNITED STATES |
Other Details:
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Languages: eng Pagination: 1453-7 Citation Subset: IM |
Affiliation:
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Department of Anesthesiology, Mayo Clinic, Rochester, Minnesota. |
Export Citation:
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APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
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Adult Blood Flow Velocity Blood Pressure Female Forearm Heart Rate Humans Male Middle Aged Muscle Contraction* Muscles / blood supply*, innervation, physiology Posture Skin / blood supply Sympathetic Nervous System / physiology* |
| Grant Support | |
ID/Acronym/Agency:
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GM-08288/GM/NIGMS NIH HHS |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
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