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The discovery of insulin

In 1921 two researchers, Fred Banting and Charles Best, were the first to discover insulin and use it to treat diabetes.

Banting and Best did not work in isolation. They were building on observations and experiments from many other researchers who had studied diabetes.

From the 1850s onwards, autopsies of people who had died from diabetes suggested that diabetes was caused when the pancreas did not function properly.

Many physicians speculated that specialised cells, called the islets of Langerhans, produced a chemical that allowed the body to regulate its blood glucose level. Diabetes was caused when this chemical was not produced.

To test their theory Banting and Best used 10 dogs. They made the dogs diabetic and then investigated treatments for the diabetes.

The result of Banting and Best's research has helped to save the lives of millions of people.

Banting Best 600X900 Copy

The scene of insulin discovery

  • In 1869, German medical student Paul Langerhans, discovered two different groups of cells in the pancreas. The acini, responsible of producing pancreatic digestive secretions, and the Islets of Langerhans, with unknown function.
  • In 1889, two German physiologists Oskar Mikowski and Joseph von Mering performed a complete pancreatectomy, this is the removal of the whole pancreas, in a lab dog, and observed that it developed diabetes.
  • In May 1921, Banting and Best discovered that islets of Langerhans were responsible for synthetising insulin, as dogs that had their pancreas removed, but kept the islets would not develop diabetes.
  • In October 1921, they confirmed their findings. They managed to keep alive a dog with severe diabetes by injecting him with extract made from the islets of Langerhans of another dog.
  • End of 1921, with the help of John Macleod and James Bertram Collip, they finally isolated and purified the antidiabetic agent: insulin.

Animal research regulation

Scientists and regulators, under current regulation, must always weigh up the benefits of new medicines with the need to use animals.

Although the majority of the UK public support the use of animals in medical research, some people have very strong opinions about testing medicines on animals. Although the use of animals in research can lead to huge breakthroughs like the discovery of insulin, it is something that must be closely monitored. For this reason, governments and other institutions decide on a set of rules that should govern whether testing can take place or not.

Current UK law about animal research

Using animals for biomedical research is highly regulated in the UK.
The law contains these principles:

  • The required information cannot be obtained using non-animal methods.
  • The likely benefits of doing the tests must outweigh any possible distress to the animals.
  • The test should use the minimum number of animals, appropriate species and cause the minimum distress.
  • Proper veterinary care should be given at all times.
  • Non-animal alternatives should be used wherever possible.
  • The person doing the test needs to be fully trained. Permission from the Home Office must be given before the study can begin.
  • The location for the tests must have all the necessary staff and facilities to ensure that animals are properly looked after.
  • Inspectors regularly monitor the locations where tests are being performed to check that all requirements are being met.