Otto Loewi

Otto Loewi was a German-born scientist who won the Nobel Prize in Physiology or Medicine in 1936 for discovering how nerve signals communicate with organs. He demonstrated this by isolating a calming chemical, later called acetylcholine, released by the vagus nerve to slow heart rate. His famous experiment involved transferring the fluid from a stimulated frog heart to another heart, which also slowed down, proving that chemicals, not just electrical signals, transmit messages between nerves and organs. This groundbreaking work laid the foundation for the understanding of neurotransmitters, the chemicals that enable communication within the nervous system.