In answering a forum post on insulin sensitivity I found these articles. They are pretty heavy going but they also get to the nitty gritty of the issue and explain specifically how glut 4 is an important insulin receptor inthe body and how it works.
This article from 2001 explains how the disruption of the GLUT 4 mechanism can affect glucose transport inside skeletal muscle. http://www.jci.org/107/10/1211/pdf
http://www.medscape.com/viewarticle/424945. I feel it may be a few years old, all the references are of 1999 so the current knowledge may have moved on but I wanted to record it here as an interesting report on glut 4 and other insulin receptors.
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