[Chemistry of adrenal cortex hormones].

You have done me the great honour of awarding me a share of the Nobel possess no more than a layman's knowledge of either medicine or physiology. I hope, therefore, that you will not take it amiss if, in the following remarks, I have to make use of a number of chemical formulae that possibly not all of you understand. It is in this case the only adequate language. If a chemist wishes to do research on the isolation of physiologically active materials, he is dependent upon the collaboration of physiologists who assist him by controllin g t he grading through experimentation on animals. When I began my researches on adrenal extracts with my colleague Herr J. von but there were only relatively few quantitative methods to determine the activity of the extracts. There were really only three: (1) The survival test (carried out especially on rats) 7. (3) The Everse-de Fremery test (adynamia after brief muscular stimula-Of these, the dog test was the most sensitive and should also have given relatively accurate results, but it was not at our disposal. On the other hand, Tests 1 and 3 were available in laboratories with which we were on friendly terms. However, both methods require relatively large amounts of material. Hence the grading of extracts could only be controlled biologically in the * Owing to lack of time, only a brief survey of the chemistry of these substances can be given here, for which reason I shall report almost exclusively on our own work. There are reviews in existence which discuss this field more exactly and give the contributions of various research groups, moreover in correct chronological order 1-6 .