Date of Award
2009
Degree Type
Thesis
Degree Name
Master of Science
Program
Kinesiology
Supervisor
Dr. Kevin ShoemakerMyogenic, Alpha-adrenergic, Norepinephrine, Phentolamine, Windkessel, Doppler ultrasound
Abstract
We tested the hypotheses that forearm vascular compliance (C) but not resistance (R) would be influenced by myogenic stimuli, and changing (A) forearm transmural pressure (TP) would influence the effect of a-adrenergic input on C and R. Continuous forearm blood flow was measured during Norepinephrine (NE; a-agonist) and during concurrent NE and Phentolamine (PH; a-antagonist) infusion with the arm above and below heart level (n=10). C was inversely related to TP (p<0.05). NE decreased C and increased R (p<0.05). PH abolished these responses. The effect of NE on AC was greater with the arm above versus below heart level (p<0.05), while AR was only observed with the arm below the heart (p<0.05). Conclusions: Myogenic changes affect forearm vascular C
independent of changes in R. Alpha -adrenergic activation reduces C and increases R. Furthermore, with NE, AC requires a high starting value of C, while AR occurs under high TP
Recommended Citation
Flamengo, Maria Fernanda, "Impact of alpha adrenergic and myogenic control on forearm vasomotor properties" (2009). Digitized Theses. 4174.
https://ir.lib.uwo.ca/digitizedtheses/4174