Some historical difficulties of the cholinergic transmission

For a very long time, arguments supporting the neuro-humoral theory, produced by the pharmacologist Henri Dale, did not convince one of the main supporters of the electrical theory, the neurophysiologist John C. Eccles. This article gives a reminder of certain technical elements of this debate between two giants, which remains one of the most symbolic arguments in the history of neurosciences. The difficulties of the cholinergic transmission often betrayed the scepticism concerning the possibility of a functional approach based on neurochemistry.