Popis: |
Insulin is a protein hormone with a long record in scientific research. In 1922 it was discovered that insulin is a hypoglycaemic hormone in dogs (Banting and Best, 1922). The succesful treatment of diabetes mellitus by injections of insulin is regarded as one of the major medical triumphs of this century. In 1955, insulin was the first protein whose primary structure was fully identified (Ryle et al., 1955). In 1972, another landmark was set by Blundell and coworkers (Blundell et al., 1972), who succeeded in crystallizing 2Zn-insulin, and revealing its three dimensional structure (3D) by rontgen-diffraction. Insulin, can therefore be considered as an outstanding model both in the field of endocrinology and molecular biology. The study of insulin has further developed during the last two decades. Various functions of insulin were discovered, in addition to its control of glucose metabolism. These “novel” functions concern the regulation of energy metabolism in general, of growth-associated processes, and of the development of the CNS (Czech et al., 1985; Froesch et al., 1985; Girbau et al., 1987). |