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                            Katz, Bernard, 1911-2003.
 
 

Sir Bernard Katz, 92, Nobelist for Nerve Chemistry Work, Dies
By SANDRA BLAKESLEE
New York Times, April 25, 2003
 

Sir Bernard Katz, who shared the 1970 Nobel Prize for Physiology or Medicine for his work explaining how messages are transmitted between nerves and muscles, died on Sunday. He was 92.

He lived in London since just after World War II.

Sir Bernard was honored, along with the physiologists Ulf von Euler and Julius Axelrod, for describing in separate lines of research precisely how brain cells talk to one another and get the body moving.

Their work helped lay the foundation for modern psychopharmacology, which explains, among other things, mechanisms for drug addiction and mental illness and the effects of certain poison gases.

Dr. Katz was fascinated by the puzzle of how electrical impulses, traveling along nerve fibers as sequences of spikes, could send a precise message to another nerve cell across gaps, called synapses, between cells.

At the time, such gaps were a no man's land. No one understood how electrical impulses from one side of the gap were translated quickly, without being changed, to impulses on the other side.

A few years before World War II, other researchers had shown that nerves that travel to muscles all over the body release a chemical called acetylcholine when the nerves are firing. Dr. Katz decided to find out how this chemical is secreted.

Using simple tools available in the 1950's, he measured the electric charges at the junction between nerves and muscles when nerves were firing. To his surprise, he also found tiny electrical readings present when nerves were not firing.

Thinking something was wrong with his machinery, Dr. Katz applied a poison to paralyze the muscles in his preparations. All activity stopped. This meant that the tiny voltage readings from resting cells must represent real activity at the nerve endings. Next, he found that the size of the electrical readings were always multiples of a tiny but exact minimum value.

That finding led to Dr. Katz's major discovery, that the resting signal between nerve and muscle depends not on individual molecules of acetylcholine but on the release of small packets, or quanta, of the chemical transmitter.

Each packet consists of several thousand molecules of acetylcholine. When the packets cross the gap between nerve and muscle, they activate a comparable signal stored on the opposite side of the gap. When nerve firing rates increase, more packets are released and muscles move.

When nerve cells are at rest, acetylcholine sends a tiny reassuring bleep telling muscles that connections are working. When packets are blocked by nerve gas, certain pesticides or some neurological disorders, nerves cannot communicate with muscles. The result is paralysis or death.

Bernard Katz was born on March 26, 1911, in Leipzig, Germany, the only son of a Russian Jewish fur trader. He studied at the Albert Gymnasium in Leipzig and the University of Leipzig, where he received a medical degree in 1934. In an autobiographical essay, he recalled many episodes of anti-Semitism during that period and began to think of ways to leave Germany. In 1934 he read an article in the British journal Nature by A. V. Hill, one of the great physiologists of the day and a strong critic of Hitler.

A year later, the 24-year-old Dr. Katz arrived in Dr. Hill's laboratory at University College in London, feeling "a little like David Copperfield who arrived bedraggled and penniless at the home of his aunt and was put into a clean hot bath." Dr. Hill often said he had accepted the young German-born scientist "as an experiment." By all accounts it was an extremely successful experiment for both men.

Dr. Katz studied in London, where he met several other young researchers who later formed a core of those who helped transform modern physiology after the war.

After earning a Ph.D. in 1938, Dr. Katz rescued his parents from Nazi Germany and moved to the laboratory of Sir John Eccles at the Kanematsu Institute in Sydney. After becoming a naturalized British citizen in 1941, he joined the Royal Australian Air Force as a radar officer and spent his time moving around the southwest Pacific and New Guinea.

As the war ended, Dr. Katz married Marguerite Penly, an Australian, and accepted a wedding present from Dr. Hill: an invitation to return to University College in London as the Henry Head Fellow of the Royal Society and assistant director of research in biophysics. He remained at the university for the rest of his career.

Dr. Katz was knighted in 1966. His wife died in 1999. He is survived by their two sons, David and Jonathan.