Online citations, reference lists, and bibliographies.
Referencing for people who value simplicity, privacy, and speed.
Get Citationsy
← Back to Search

Angiogenic Growth Factor MRNA Responses In Muscle To A Single Bout Of Exercise

E. C. Breen, E. C. Johnson, H. Wagner, H. M. Tseng, L. A. Sung, P. D. Wagner

Save to my Library
Download PDF
Analyze on Scholarcy Visualize in Litmaps
Reduce the time it takes to create your bibliography by a factor of 10 by using the world’s favourite reference manager
Time to take this seriously.
Get Citationsy
A major adaptation to exercise is new capillary formation in skeletal muscle. On the basis of angiogenesis in tumors and during development, several angiogenic growth factors may be involved, including vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), and transforming growth factor-beta 1 (TGF-beta 1). In 9-wk-old female Wistar rats, mRNA expression for these three growth factors in gastrocnemius muscle was examined by quantitative Northern analysis after a single 1-h run at 15 or 20 m/min at 10 degrees incline in room air. A third group ran at 15 m/min in 12% O2, and resting control groups were included at inspired O2 fractions of 0.21 and 0.12. Exercise significantly increased mRNA levels two- to fourfold, which was evident over the first 4 h postexercise; by 8 and 24 h, mRNA levels returned to baseline. For all three factors, mRNA levels were significantly higher after exercise at 20 than at 15 m/min. Hypoxia at rest doubled VEGF and TGF-beta 1 message but had no effect on bFGF. Hypoxic exercise further raised VEGF mRNA levels but had no effect on the other factors. We suggest that VEGF, bFGF, and TGF-beta 1 may be involved in the angiogenic response to exercise and that reduced intracellular PO2 (as occurs during normoxic exercise) may be part of the stimulus to such growth factor production.