What is this vagus stuff?

Henry A. Lester, PhD

Actually, it's Vagusstoff (literally translated from German as "Vagus Substance") refers to the substance released by stimulation of the vagus nerve which causes a reduction in the heart rate. Discovered in 1921 by physiologist Otto Loewi, vagusstoff was the first confirmation of chemical synaptic transmission and the first neurotransmitter ever discovered. It was later confirmed to be acetylcholine, which was first identified by Sir Henry Hallett Dale in 1914. Because of his pioneering experiments, in 1936 Loewi was awarded the Nobel Prize in Physiology or Medicine, which he shared with Dale. Thanks to Dr. Henry Lester of Cal Tech for informing me of this interesting bit of neuro-history through his free online course entitled "Drugs and The Brain". The information provided here is taken from the Wikipedia article on the topic.