Setting the standards for a new science: Edward Schäfer and endocrinology

FOLLOWING Brown-Sequard's report in 1889 of the rejuvenating effects of injections of extracts of the testes, physicians and physiologists began to search for other potent "internal secretions" in animal tissues. They expected to be able to isolate powerful new drugs which would be useful in the treatment of a variety of intractable diseases. Remission of conditions treated by a series of such injections reinforced that expecta- tion. Myxoedema yielded to treatment by thyroid extract, and physicians hoped to be able to cure diabetes by injections of pancreatic extract. The actual discovery of these hypothetical substances was not so straightforward, however. The criteria of remission were not well defined, and the physiological responses to these extracts were unknown.