Calcium glucose transport and insulin action
In insulin-sensitive cells, the glucose transport system serves the purpose of controlling the access of glucose to the cytoplasm. Like the other rate-limiting processes along the cellular metabolic pathways, the transport of glucose seems to be stimulated by either endogenous or exogenous factors
For instance, we know that when the need for metabolizable substrate is increased during anoxia or contractile activity, the uptake of glucose is increased. It seems likely that this is the result of an activation of the glucose transport system brought about by endogenous factors, i.e. agents generated inside the cell following the metabolic perturbation
The very same agents may be of importance for the activation induced by exogenous factors like insulin or other hormones
If this is the case, it might even be possible to identify one common denominator for all the many conditions and factors which are known to stimulate glucose transport - a compound which in ideally all of these instances is made available at the plasma membrane and which can be shown to induce direct activation of the glucose transport system
Ten years ago, Holloszy and Narahara (1965) proposed that the Ca2+ ion might be an important activator for the glucose transport system. This possibility may be tested by examining the consequences of exposing the glucose transport system to calcium
Important Sources/ references to get This topic
Biochemistry of Membrane Transport book.pdf
Ca+2 fluxes and insulin action in cardiac and skeletal muscles
Calcium, Glucose Transport and Insulin Action
Harpers illustrated biochemistry 28th ed