If nerves send signals via chemicals, then why do we never run out of them?

Question

If nerves send signals via chemicals, then why do we never run out of them?

In: Biology

Answer 1

You can “run out of them” for brief periods of time. Capsaicin cream, made from the same capsaicin found in hot peppers, is used at various strengths to treat chronic and acute pain. You rub the capsaicin on the area of pain (using gloves for the heavy duty stuff) and it first makes the nerves all fire quickly (and painfully) and empty out all of those neurotransmitter chemicals. You then get pain relief during the time it takes the nerves to reabsorb all those chemicals they “lost.” So, the nerves “run out of them,” but your body does not. There is a little bit of oversimplification there, but I hope you get the idea.