| Longitudinal cryosection of quadriceps from 7 month |
old mice stained with Rabbit 2 polyclonal antibody
to dystrophin. Nuclei are stained with hematoxylin (blue).
Cropped from doi:10.1371/journal.pone.0002604.g003
In addition to consuming triglycerides, red muscle can also consume lactic acid. Lactic acid is produced during exercise, and its build up is associated with the fatigue we feel as a result of exercise. Scientists at the University of Basel have shown that a protein, PGC-1 a, exhibits increased expression in endurance trained muscle.
To test the effects of PGC-1 a the scientists created mice that continuously expressed high levels of PGC-1 a. Endurance was monitored in mice for 1 hour on a treadmill. Mice that had previous endurance training were able to complete the tests without loss of performance and had low lactic acid levels while those without prior training had high lactic acid levels and were unable to complete test without loss of performance. Mice created that express PGC-1 a at high levels had low levels of lactic acid and were able to maintain performance until the end of training even though they not had previous endurance training.
The finding were published in the PNAS article entitled: Skeletal musclePGC-1α controls whole-body lactate homeostasis through estrogen-relatedreceptor α-dependent activation of LDH B and repression of LDH A