Is this the correct path for Muscle fiber Hyperplasia (simplified)=
muscle fiber hypertrophy -->
satellite cell proliferation -->
myogenesis (via-- growth factor (FGF), the insulin-like growth factors (IGF-I and -II), and transforming growth factor-beta (TGF-beta)-->
new muscle fiber.
Does hyperplasia occur in postnatal phase of humans, and are stem cells still present during the postnatal phase? Answers---
What causes satellite cell proliferation exactly?
http://www.ncbi.nlm.nih.gov/entrez/query.f...5&dopt=Abstract
http://www.ncbi.nlm.nih.gov/entrez/query.f...8&dopt=Abstract
Anyone believe muscle fiber hyperplasia can occur in humans? How? -Answers--
Meta-analysis paper on hyperplasia in animals--
http://jap.physiology.org/cgi/content/full...date=11/30/2003
DISCUSSION
This meta-analysis attempted to quantify the magnitude of change in muscle (particularly muscle fiber number) as a result of mechanical overload. Across all designs and categories, mechanical overload resulted in increases in muscle mass, muscle fiber area (hypertrophy), and muscle fiber number (hyperplasia). Not surprisingly, increases in fiber area were approximately twice as great as increases in fiber number. It appears that hyperplasia in animals is greatest when certain types of mechanical overload, particularly stretch, are applied. The results of this investigation are similar to a recent narrative review that concluded that muscle fiber hyperplasia 1) consistently occurs as a result of chronic stretch, 2) rarely occurs with overload in the form of compensatory hypertrophy, and 3) has produced mixed results when overload in the form of exercise is employed (8). Although it is well established that mechanical-overload training results in increased fiber area (hypertrophy), and thus increases in muscle mass, the contribution of increased fiber number (hyperplasia) to increases in muscle mass has been more controversial. However, there now exists quantitative evidence to support the fact that certain types of overload, particularly stretch, result in increases in muscle fiber number. Unfortunately, it is beyond the scope of this investigation to examine the processes (satellite cell proliferation and longitudinal fiber splitting) responsible for such changes.
http://www.jhc.org/cgi/content/abstract/50/8/1097
Testosterone inject/ satellite cell proliferation
http://ajpendo.physiology.org/cgi/content/...ract/285/1/E197
http://www.ncbi.nlm.nih.gov/entrez/query.f...8&dopt=Abstract
Math problem:
They gave 0.25 mg/100 g body weight of testosterone to this rat, which would be how much test for a 200lb male?
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