Human skeletal muscle feed arteries: evidence of regulatory potential.
OBJECTIVE
Recently, it has been recognized that human skeletal muscle feed arteries can be harvested during exploratory surgery for melanoma. This approach provides vessels for in vitro study from a wide spectrum of relatively healthy humans. Although, the regulatory role of skeletal muscle feed arteries in rodent models has been documented, whether such vessels in humans possess this functionality is unknown.


METHODS
Therefore, skeletal muscle feed arteries (~950 μm OD) from 10 humans (48 ± 4, 27-64 years) were studied using pressure myography. Vessel function was assessed using potassium chloride (KCl), phenylephrine (PE), acetylcholine (ACh) and sodium nitroprusside (SNP) concentration-response curves (CRCs) to characterize non-receptor and receptor-mediated vasoconstriction as well as endothelium-dependent and independent vasodilation respectively. To understand the physiological relevance of the diameter changes as a result of pharmacological stimulation, the estimated conductance ratio (CR) was calculated.


RESULTS
Vessel function protocols revealed significant vasoconstriction in response to PE and KCl (35 ± 6; 43 ± 9%vasoconstriction, respectively) and significant vasodilation with ACh and SNP (85 ± 7; 121 ± 17% vasodilation, respectively). Both PE and KCl significantly reduced the CR (0.26 ± 0.05 and 0.23 ± 0.07, respectively), whereas ACh and SNP increased the CR (2.56 ± 0.10 and 5.32 ± 1.3, respectively).


CONCLUSIONS
These novel findings provide evidence that human skeletal muscle feed arteries are capable of generating significant diameter changes that would translate into significant changes in vascular conductance. Thus, human skeletal muscle feed arteries likely play a significant role in regulating vascular conductance and subsequently blood flow in vivo.
Geriatric Research, Education, and Clinical Center, George E. Whalen VA Medical Center, Salt Lake City, UT 84148, USA. steven.ives@utah.edu
S J
SJ
Ives
R H I
RH
Andtbacka
S-Y
SY
Park
A J
AJ
Donato
J R
JR
Gifford
R D
RD
Noyes
L A
LA
Lesniewski
R S
RS
Richardson
D000328:Adult; D001158:Arteries / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000098:blood supply*; D009213:Myography; D012039:Regional Blood Flow; D014661:Vasoconstriction / Q000187:drug effects; D014662:Vasoconstrictor Agents / Q000494:pharmacology; D014664:Vasodilation / Q000187:drug effects; D014665:Vasodilator Agents / Q000494:pharmacology
D014662:Vasoconstrictor Agents; D014665:Vasodilator Agents