Loewi

Loewy, A. G., Siekevitz, P., Menninger, J. R., Gallant, J. A. N., 1991. Cell Structure and Function. Philadelphia Saunders College Publishing. 

The concept of chemical neurotransmission originated in the 1920s with the classic experiments of Otto Loewi (which were themselves inspired by a dream), who demonstrated that by transferring the ventricular fluid of a stimulated frog heart onto an unstimulated frog heart he could reproduce the effects of a (parasympathetic) nerve stimulus on the unstimulated heart (Loewi Navratil, 1926). Subsequently, it was found that acetylcholine was the neurotransmitter released from these parasympathetic nerve fibers. As well as playing a critical role in synaptic transmission in the autonomic nervous system and at vertebrate neuromuscular junctions (Dale, 1935), acetylcholine plays a central role in the control of wakefulness and REM sleep. Some have even gone as far as to call acetylcholine a neurotransmitter correlate of consciousness (Perry et al., 1999). 

ACh was first proposed as a mediator of cellular function by Hunt in 1907, and in 1914 Dale [2] pointed out that its action closely mimicked the response of parasympathetic nerve stimulation (see Ch. 10). Loewi, in 1921, provided clear evidence for ACh release by nerve stimulation. Separate receptors that explained the variety of actions of ACh became apparent in Dale s early experiments [2]. The nicotinic ACh receptor was the first transmitter receptor to be purified and to have its primary structure determined [3, 4]. The primary structures of most subtypes of both nicotinic and muscarinic receptors, the cholinesterases (ChE), choline acetyltransferase (ChAT), the choline and ACh transporters have been ascertained. Three-dimensional structures for several of these proteins or surrogates within the same protein family are also known. 

Loewi O (1921) Uber humorale Ubertragbarkeit der herznervenwirkung. Pflugers Arch Ges Physiol 189 239-242... 

The concept of a neurotransmitter originated in the 1920s with the acetylcholine molecule. Henry Dale and Otto Loewi originated the concept of chemical transmission of nerve impulses. These scientists shared the 1936 Nobel Prize in Physiology or Medicine for this work. Acetylcholine was also the first neurotransmitter for which the structure was determined. Otto Loewi accomplished that task, also in 1936. 

Otto Loewi (1873-1961), professor of pharmacology at the University of Graz, awoke one night with a brilliant idea. The next day he went to his laboratory and in one of the most definitive experiments in the history of biology, brought proof of the chemical mediation of nerve impulses. 

AGerman-American physiologist, Otto Loewi discovered the first neurotransmitter, acetylcholine. Loewi was born in Frankfurt- am-Main on June 3, 1873. He attended the University of Strasbourg, from which he received his medical degree in 1896. He then worked for a period of time at University College in London, the University of Vienna, and the University of Graz (Austria). 

For his discovery of acetylcholine, Loewi was awarded a share of the 1936 Nobel Prize in physiology or medicine. As one condition of being allowed to leave Austria in 1938, he was required to hand over the cash award that was given him as part of his Nobel Prize. 

When Germany invaded and conquered Austria in 1938, Loewi was placed under arrest. Fortunately, he was eventually released from prison and was able to escape the country, traveling first to Belgium and England and then to the United States. He was then appointed to a position at the New York University College of Medicine, where he remained until 1946. He died in New York City on December 25,1961. 

Acetylcholine (ACh) has been known as a neurotransmitter since the mid-1920s. In fact, the demonstration that acetylcholine is the Vagusstoff ( vagus-substance ) released from the vagus nerve to modulate heart function was the first proof for the chemical mediation of nerve impulses (Loewi and Navratil, 1926). In the peripheral nervous system, ACh is found as the neurotransmitter in the autonomic ganglia, the parasympathetic postganglionic synapse, and the neuromuscular endplate. 

Loewi, O. and Navratil, E. (1926) Uber humorale Ubertragbarkeit der Herznervenwirkung. X. Mitteilung. Uber das Schicksal des Vagusstoff. Pflugers Arch Gesamte Physiol 214 678-688. 

Loewi used frogs in his experiments. He exposed the vagus nerve and heart of one frog, then stimulated the nerve artificially by shocking it with an electrical current. The heart began to beat faster. Loewi... 

The experiments of Loewi, Dale, Feldberg, Gaddum, and their colleagues were conclusive, yet they did not rule out the possibility of other... 

Hauptmann accidentally discovers barbiturates as anticonvulsants (see 1903, 1882) Loewi demonstrates that acetylcholine is a neurotransmitter Banting and Best purify insulin as treatment for diabetes Szent-Gyorgyi isolates ascorbic acid (Vitamin C)... 

Henry H. Dale and Otto Loewi Physiology/Medicine Acetylcholine release at nerve endings... 

Attack by Loewis acid leads to the thermodynamically most stable cation. 

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