Acetylcholine is an organic chemical that functions in the brain and body of many types of animals and humans as a neurotransmitter—a chemical message released by nerve cells to send signals to other cells, such as neurons, muscle cells and gland cells.
Atropine is an alkaloid contained in plants such as belladonna. Since Atropine has some functional groups similar to that of acetylcholine, it competes with acetylcholine in binding to the acetylcholine receptors and inhibits their actions.
During drug proving of belladonna tincture, Atropine molecules contained in it competitively bind to acetylcholine receptors and inhibit their actions. These inhibition of acetylcholine receptors result in a lot of deviations in various bio-chemical pathways involved, which is expressed through diverse groups of subjective and objective symptoms we see in the materia medica of BELLADONNA.
Post-avogadro dilutions of BELLADONNA contains MOLECULAR IMPRINTS of ATROPINE, along with those of many other chemical molecules contained in it.
When a person in disease shows symptoms of BELLADONNA, it means the pathogenic molecules that cause particular disease condition contain some chemical molecules that bind to and inhibit the acetylcholine receptors. Molecular imprints of atropine will have conformational affinity to those pathogenic molecules, by which they can bind the pathogenic molecules and deactivate them. That is exact biological mechanism involved in the therapeutic actions of post-avogadro dilutions of BELLADONNA.
ATROPINE is not the only chemical molecule contained in belladonna, and as such, this explanation is only a partial study of BELLADONNA.