|
Definition: "An ergogenic aid is any substance or phenomenon that enhances performance "
|
|
||||||||
06.11.2008 |
|
|
Growth hormone won't give you definition when you're young
The effect of growth hormone [structure shown below] on the fat reserves depends on age, endocrinologists at Ohio University concluded after doing research on transgenic mice. The mice, which started to manufacture more growth hormone after they had been modified with growth hormone genes, became fatter while still young. At an older age they developed better definition.
The researchers introduced genes for bovine growth hormone into the mouse embryos' genome, and then did experiments with the animals in which the new genes were expressed. In these animals the concentration of growth hormone in the blood increased by a factor of four hundred. The concentration of IGF-1, an anabolic hormone that the liver and muscles manufacture if there is a large amount of growth hormone circulating in the body, doubled.
The researchers monitored the changes in body composition of the mice using NMR. The animals put on weight as a result of the intervention, as you can see in the graph below. NT = non transgenic.
The curves for the female animals were almost the same.
In the beginning, the fat percentage in the genetically modified mice was higher than in the non-transgenic mice. Only after sixteen weeks did the bGH mice start to become leaner than the ordinary mice. Mice usually get fatter as they age, but the bGH genes stopped that from happening.
Leucine delays the breakdown of protein in muscles. In the old rats the anti-oxidant mix enhances this effect.
If you translate mouse age into human age, then sixteen-week-old mice already got their drivers' license long ago. They can already vote and have left home, and they are even starting to get grey hairs.
The bGH mice's livers had doubled in size.
The experiment lasted a year. Ordinary mice in captivity live for up to three years, but the researchers decided to stop the experiment after 56 weeks. They did so for methodological reasons: mice transformed with new growth hormone genes do not live to be as old as ordinary mice. But that's another story... [To be continued]
Sources:
|
|
