[Scientific contribution of Sutherland's "the second messenger hypothesis"].

Signal transduction is one of the most important fields of life science. The discovery of cAMP and description of the second messenger hypothesis by Sutherland is the landmark of signal transduction. In this paper, the background and course of cAMP discovery were demonstrated and at the same time the content and significance of the second messenger hypothesis were illustrated, so scientific contribution of the second messenger hypothesis can be approximately understood.