Dale, Henry

Dale, Sir Henry (1953). A chemical phase in the transmission of nervous effects. Endeavour, AT, 117. 

Dale, Sir Henry 77 Delay 77 Delay, Jean 77 delocalized orbitals 233 Deniker, Pierre 77 Density Functional Theory 55,228,241,271,278 deposition conditions 168 design of the Sawatzky-Kay apparatus 152 Dess-Martin oxidation 11 detailed atomic-level representation 92 determinant 279 diastereoface selectivity 22,... 

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. 

Henry Dale first established that there were two different receptors for acetylcholine, the muscarinic and nicotinic, and it is now known that there are hve different classes of muscarinic and an ill-dehned number of nicotinic receptors. Different receptors were originally identihed by pharmacological methods but molecular biological techniques now provide very sensitive and precise means of identify-... 

The metabolic unity of the neuron requires that the same transmitter is released at all its synapses. This is known as Dale s Law (or principle) which Sir Henry Dale proposed in 1935. Dale s Law only applies to the presynaptic portion of the neuron, not the postsynaptic effects which the transmitter may have on other target neurons. For example, acetylcholine released at motor neuron terminals has an excitatory action at the motor neuron junction, whereas the same transmitter released at vagal nerve terminals has an inhibitory action on the heart. 

Sir Henry Dale noticed that the different esters of choline elicited responses in isolated organ preparations which were similar to those seen following the application of either of the natural substances muscarine (from poisonous toadstools) or nicotine. This led Dale to conclude that, in the appropriate organs, acetylcholine could act on either muscarinic or nicotinic receptors. Later it was found that the effects of muscarine and nicotine could be blocked by atropine and tubocurarine, respectively. Further studies showed that these receptors differed not only in their molecular structure but also in the ways in which they brought about their physiological responses once the receptor has been stimulated by an agonist. Thus nicotinic receptors were found to be linked directly to an ion channel and their activation always caused a rapid increase in cellular permeability to sodium and potassium ions. Conversely, the responses to muscarinic receptor stimulation were slower and involved the activation of a second messenger system which was linked to the receptor by G-proteins. 

I must also acknowledge the many friends and display operators with whom I have enjoyed sharing my passion for hreworks over the years. These include Ray Harrison, Henry Dunlop, Campbell Wilson, Chris Wilson, Ken Norton, Dave Laurence, Andy Goodwin and Debbie, Jonathon Webb, Steve Cornall, Dale Sullivan, Roly Harrison, the late Wally Betts, Kevin Russell, Robert Stevens and my number two daughter, Jane. 

Classical studies by Sir Henry Dale demonstrated that the receptors activated by muscarine, an alkaloid isolated from the mushroom Amanita muscaria, are the same receptors activated by ACh released from parasympathetic nerve endings, from which the general notion that muscarinic agonists have parasympathomimetic properties was born. This conclusion is true but incomplete, and we now know that muscarinic receptors have a broader distribution and many functional roles. To understand the actions of cholinomimetic drugs it is essential to recognize that muscarinic receptors (1) mediate the activation of effectors by ACh released from parasympathetic nerve... 

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

The next major step forward in deciphering the mechanisms of synaptic transmission occurred in the neuropharmacological studies of Henry Dale, Otto Loewi, Wilhelm Feldberg, and their colleagues. Although, as in the discovery of the synapse as an intercellular noncontinuous junction, many individuals contributed, Loewi is generally credited with the single decisive experiment. This is probably fair, since... 

Rather more specialized are the chemical methods for the determination of acetylcholine, but a short account has been given of their historical development in a brief correspondence in 1968 between Sir Henry Dale, D. J. Jenden, and B. Holmstedt, who wrote it up for publication.192... 

The question was raised by the Society s Treasurer, Thomas Merton, that the election of a woman was a break in the traditions of the Society. In response, Henry Dale, the previous Director of the National Institute for Medical Research, commented However much one might wrap it up, the question which we should put could only mean one thing — Do you or do you not wish the Council to continue a discrimination against women candidates which the Law has removed 99... 

Feldberg, W. S. (1970). Henry Hallett Dale, 1875-1968. Biographical Memoirs of Fellows of the Royal Society 16 77-174. 

His neurological researches during the period 1921-26 provided the first proof that chemicals were involved in the transmission of impulses from one nerve cell to another and from neuron to the responsive organ. It was for his discovery of the chemical transmission of nerve impulses that he received the Nobel Prize in physiology or medicine in 1936, jointly with Sir Henry Dale. Loewi spent his years investigating the physiology and pharmacology of metabolism, the kidneys, the heart, and the nervous system. He became an American citizen in 1946 and died on December 25, 1961. 

Henry Hallett Dale, Otto Loewi Chemical transmission of nerve impulses... 

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