The metabolism of acetylcholine in brain tissue preparations.

The function of the central nervous system in the body is to control its response to physiological needs, and for the most part these needs are communicated to the central nervous system by messages sent through the afferent nerves. It responds by sending out impulses, which travel through the efferent nerves to the effector organs, it has been known since the days of Galvani that the stimulation of a nerve, whether by natural or artificial means, produces an excitation in the effector organ, and that this excitation is propagated in the nerve, and is accompanied by an electrical wave. It was generally believed that the electrical wave travelled to the effector, and there elicited the specific response. The action of a nerve may be subdivided into three distinct phases: a stimulus reaching a neuron must initiate an impulse; the impulse, once initiated, must be propagated along the axon; and finally, it must be transmitted either to a second neuron or to an effector cell. The supposition that electrical phenomena can account for this chain of events has been widely held, but there are certain parts of this purely electrical theory as originally stated which are very difficult of proof, and some modifications appeared necessary.[...