I come from Physics, not biology. My understanding is that without sufficient oxygen present, the Krebs cycle terminates in lactic acid formation for the body to later continue the reaction when oxygen becomes more available for oxidation.
If I understand correctly, for a period of time there will be an excess of Lactic acid in the body which will change the pH of the cell. How does that translate into the perception of pain?
I was taught in a Cognitive Science class that pain is cause my a neurotransmitter (Substance P) which is released due to bodily damage. This might not be entirely true, please correct this if wrong.
So my thinking is:
Lack of Oxygen => Lactic Acid production => ... (?) => Substance P => Pain
Thus possibilities for the "..." would be, bodily damage => Substance P, or Lactic Acid signals Substance P release without a need for bodily damage.
My question is then, how do I get from Lactic Acid to Pain?