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An accidental discovery led to the
Nobel Prize for Canadian researchers
The causes of diabetes (pronounced di' e-be' tis), a disease
known for centuries, were explored by German doctors over a
century ago,and further established by two Canadian scientists,
who, in 1922, worked in a laboratory at the University of Toronto.
The German researchers were interested in studying digestion,
and used domestic dogs in experiments. The doctors performed
surgery on the animals and removed a small gland located in the
abdomen, just below the stomach. The gland was called the "pancreas"
(named from the Greek words "pan," meaning "all," and "kreas", meaning
"flesh"), and helps to digest food. The gland, when taken from beef,
is considered a delicacy on the dinner table because of its
nutritious qualities and given the more familiar sounding name,
"sweetbread." It is rich in proteins and enzymes, and like the
liver, is an extremely healthy food.
The research doctors, whose original purpose was to
study digestion, accidentally discovered something else. In the
old days of medical research, animals were usually kept within
the laboratory, fed and cared for by laboratory assistants.
Facilities were not as well equipped as they are today, and
animals were housed in the same rooms where scientists carried
out experiments.
In the original laboratory, animals deposited their
liquid wastes (urine) in the corner of the room. In summer, the
windows were typically open, and on occasion, insects, such as
ants, would get into the laboratory. The remarkable thing was
that ants, in large numbers, tended to be attracted to the dog
urine. A laboratory assistant first noticed that many ants
were clustered around the urine, which stimulated his curiosity
and eventually led the researchers to their famous discovery.
The doctors tested the urine and were surprised that samples
were extremely high in sugar, indicating high blood sugar levels.
It was, therefore, logically reasoned that the pancreas, which
had been removed, had something to do with the control of blood
sugar levels.
In Canada, Drs. F.G. Banting and C.H. Best demonstrated
that a special chemical (called a "hormone", from the Greek
word "horme" for "impulse") keeps the level of sugar at the proper
level. This area of medical research is called "endocrinology",
and involves circulating hormones and the glands from which
hormones are made. Banting, in 1923, was the first Canadian to
receive a Nobel Prize for medicine, and a replica of the
Banting-Best laboratory has been restored for visitors at
the Ontario Science World in Toronto.
When the pancreas is removed, the source of the chemical
is also removed, and sugar levels rise above normal. High
sugar levels are unhealthy and can be dangerous. If someone
has a defective pancreas, however, a treatment exists.
Patients can give themselves daily injections of the
replacement hormone (called "insulin", from the Latin
word "insula" meaning "island", describing the appearance
of the cells in the pancreas) and, thus, control their blood
sugar levels. Sugar, after all, is a vital chemical that is
necessary for all living things to carry out their activities.
The interesting point about this discovery, of a disease
affecting millions of North Americans, is that the full
name of the disease is "diabetes mellitus". "Diabetes" comes
from the Greek word for "siphon", and implies that a lot
of urine is made. The second term,"mellitus" comes from the
Latin word, "mel" which means "honey", and was used because
the urine was sweet. The ants, however, were the real
discoverers, indicating to the laboratory workers that the
urine had special properties worth investigating.
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