Life / Neuroscience & Psychology

Chemical nerve signalling

Otto Loewi's frog-heart experiment (1921) proved that nerve cells signal with chemical messengers.

Otto Loewi stimulated the vagus nerve of one frog heart and showed that the fluid around it slowed a second heart, proving that the nerve releases a chemical, later identified as acetylcholine. He shared the 1936 Nobel Prize with Henry Dale. It settled the 'soup versus sparks' debate for synapses and led to the neurotransmitter concept that underlies psychiatric drugs.