insulin and nervous system

[Guest guest]

Someone asked about the relationship between insulin and the autonomic

nervous system, but can't find the email.

These molecules have so many actions it is astounding and hard to keep track

of. Here is a very simple, short answer to the question:

Insulin stimulates cGMP (cyclic guanosine monophosphate) and inhibits cAMP

(cyclic adenosine monophosphate). cAMP is an agent of the sympathetic nervous

system, and adrenaline acts *through* cAMP (adrenaline doesn't actually enter

cells, but attaches to a cell and causes an increase in cAMP in the cell).

cGMP causes calcium ions to move into storage centers in muscle cells, acting as

a muscle relaxant (calcium is responsible for muscle contractions, so your

level of tone [constant, involuntary contraction] is determined by the amount of

calcium floating around).

So insulin causes muscle relaxation and essentially disables the adrenaline.

There's one reason it's pretty stupid to practice carb loading before running

a marathon! And one reason athletes would obviously improve performance on a

low-carb diet.

Chris