Cellular properties of extensor carpi radialis brevis and trapezius muscles in healthy males and females.
In this study, we sought to determine whether differences in cellular properties associated with energy homeostasis could explain the higher incidence of work-related myalgia in trapezius (TRAP) compared with extensor carpi radialis brevis (ECRB). Tissue samples were obtained from the ECRB (n = 19) and TRAP (n = 17) of healthy males and females (age 27.9 ± 2.2 and 28.1 ± 1.5 years, respectively; mean ± SE) and analyzed for properties involved in both ATP supply and utilization. The concentration of ATP and the maximal activities of creatine phosphokinase, phosphorylase, and phosphofructokinase were higher (P < 0.05) in ECRB than TRAP. Succinic dehydrogenase, citrate synthase, and cytochrome c oxidase were not different between muscles. The ECRB also displayed a higher concentration of Na(+)-K(+)-ATPase and greater sarcoplasmic reticulum Ca(2+) release and uptake. No differences existed between muscles for either monocarboxylate transporters or glucose transporters. It is concluded that the potentials for high-energy phosphate transfer, glycogenolysis, glycolysis, and excitation-contraction coupling are higher in ECRB than TRAP. Histochemical measurements indicated that the muscle differences are, in part, related to differing amounts of type II tissue. Depending on the task demands, the TRAP may experience a greater metabolic and excitation-contraction coupling strain than the ECRB given the differences observed.
a Department of Kinesiology, University of Waterloo, Waterloo, ON N2L 3G1, Canada.|b Centre for Research Expertise for the Prevention of Musculoskeletal Disorders (CRE-MSD), Waterloo, Ontario, Canada.
Howard J
HJ
Green
a Department of Kinesiology, University of Waterloo, Waterloo, ON N2L 3G1, Canada.|b Centre for Research Expertise for the Prevention of Musculoskeletal Disorders (CRE-MSD), Waterloo, Ontario, Canada.|c Disability Assessment Services Inc., Waterloo, Ontario, Canada.
Don
D
Ranney
a Department of Kinesiology, University of Waterloo, Waterloo, ON N2L 3G1, Canada.
Margaret
M
Burnett
a Department of Kinesiology, University of Waterloo, Waterloo, ON N2L 3G1, Canada.
Sobia
S
Iqbal
a Department of Kinesiology, University of Waterloo, Waterloo, ON N2L 3G1, Canada.
Natasha
N
Kyle
a Department of Kinesiology, University of Waterloo, Waterloo, ON N2L 3G1, Canada.
David
D
Lounsbury
a Department of Kinesiology, University of Waterloo, Waterloo, ON N2L 3G1, Canada.
Jing
J
Ouyang
a Department of Kinesiology, University of Waterloo, Waterloo, ON N2L 3G1, Canada.
A Russell
AR
Tupling
a Department of Kinesiology, University of Waterloo, Waterloo, ON N2L 3G1, Canada.
Ian C
IC
Smith
a Department of Kinesiology, University of Waterloo, Waterloo, ON N2L 3G1, Canada.
Riley
R
Stewart
d Mind Body Medicine, The RSI Clinic, Toronto, Ontario, Canada.|e Departments of Family Medicine and Anaesthesiology & Pain Medicine, University of Washington, Seattle, Washington, USA.
Heather
H
Tick
D000328:Adult; D004551:Elbow Joint / Q000166:cytology* / Q000378:metabolism*; D056966:Excitation Contraction Coupling / Q000502:physiology; D005260:Female; D005542:Forearm / Q000502:physiology; D006304:Health Status; D006801:Humans; D008297:Male; D053858:Metabolic Networks and Pathways / Q000502:physiology; D012519:Sarcoplasmic Reticulum / Q000378:metabolism; D064171:Superficial Back Muscles / Q000166:cytology* / Q000378:metabolism*
couplage excitation–contraction; distribution des types de fibre; excitation–contraction coupling; fibre type distribution; metabolic pathways; substrates; substrats; transporters; transporteurs; voies métaboliques