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The complications frequently accompanying diabetes, such as impairment of
vision and of kidney function, are now thought to result from the lack of
continuous control of blood glucose concentrations. The healthy pancreas, in
response to increases in blood glucose concentration, releases small quantities
of insulin throughout the day and thereby maintains the concentration within
physiological limits (nomoglycemia). But the diabetic generally receives only
one large dose daily. The diabetic’s blood glucose concentration can thus
fluctuate greatly during the interval between doses, and it has been suggested
that the complication result from the periods of high concentrations of blood
glucose (hyperglycemia). Many investigators thus believe that restoration of
normoglycemia might halt the progression of such complications and perhaps even
reverse them.
There are three primary techniques that have been investigated for
restoration of normoglycemia. They are: transplantation of whole, healthy
pancreases; transplantation of islets of Langerthan, that portion of the
pancreas that actually secretes insulin, and implantation of artificial
pancreases. There has, in fact been a great deal of success in the development
of these techniques and each seems, on the whole, promising. Nonetheless, it
will undoubtedly be many years before any one of them is accepted as a treatment
for diabetes.
To many people, the obvious approach would seem to be simply to transplant
pancreases from cadavers in the same manner that kidneys and other organs are
routinely transplanted. That was the rationale in 1966 when the first recorded
pancreas was performed. Between 1960 and 1975, there were forty-six pancreas
transplants in forty-five other patients in the United States and five other
countries. But only one of these patients is still alive with a functioning
graft and surgeons have found that the procedure is not simple as they once
thought.
The surviving patient has required no insulin since the operation. Another
patient survived 638 days without requiring insulin. And one patient survived a
transplantation for more than a year, but died when he chose not to take
immunosuppressive drugs. These results, though meager, suggest that the
procedure has the potential for success.
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