PERIPHERAL BLOOD FLOW CHARACTERISTICS

Project: Research project

Project Details

Description

The research will investigate mechanisms responsible for peripheral
vasodilation. Our hypotheses are: 1) In CHF, more than one mechanism is
responsible for impaired vasodilation, one is related to salt and water
retension. The second is postulated to be due to detraining; 2) training
leads to enhanced vasodilation that is mediated by structural changes
(independent of metabolic differences). This enhanced vasodilation is
related in part to training induced changes in vessel size. These changes
in size may be mediated by the release of endothelial substances; 3)
training leads to changes in somatic afferent stimulation that are due to
differences in local metabolism. Thus, training induced changes in
metabolism can affect blood flow in uninvolved vascular beds but these
changes in metabolism do not effect local vasodilation; 4) the sympathetic
nervous system plays an integral role in increasing resistance in
metabolically active areas in distant areas. This system may be modulated
by training.

This revised proposal uses a number of models to address these questions.
1) Human peripheral vasodilation is studied in response to ischemia and
forearm work. Blood flow is measured noninvasively with strain gauge
plethysmography. 2) Human large blood vessel diameter is measured by
combined plethysmography and brachial artery velocity measurements
(area=flow/velocity). 3) Indices of peripheral metabolism are studied
using 31P NMR spectroscopy. 4) Somatic afferent nerve stimulation will be
studied by using microneurographic techniques to investigate the efferent
response to afferent stimulation. 5) This intrinsic dilatory
characteristics of blood vessels will be studied using rat aorta rings and
segments.

The studies proposed will be part of the candidate's training program
designed to improve his skills and understanding of 1) human blood flow; 2)
muscle metabolism; 3) the sympathetic nervous system in human beings (using
microneurography); and 4) basic mechanisms of vasodilation in an animal
model.

A newly refurbished laboratory, equipped for exercise and plethysmography
studies, will be at the candidate's disposal. Also, a 350 sq ft animal
laboratory is available. Preliminary NMR studies are currently underway
and plans to learn microneurography have been made.

The Hershey Medical Center is supportive of these efforts.
StatusFinished
Effective start/end date1/1/901/1/90

Funding

  • National Heart, Lung, and Blood Institute

Fingerprint Explore the research topics touched on by this project. These labels are generated based on the underlying awards/grants. Together they form a unique fingerprint.