Relaxin as a New Hormone*

RELAXIN was described as a hormone some 55 years ago but despite some persistent pioneering work, passed into relative obscurity for a long period of time. The present status of relaxin is such that it directly impinges on reproductive endocrinology and perhaps on those endocrinologists who appreciate that connective tissue metabolism is controlled by hormones and who wish to share in the task of refurbishing a hormone long left on the shelf. There is no question but that work on relaxin was at a low ebb for 40 years after its initial discovery by Frederick Hisaw in 1926. Certainly part of the resurgence of work on relaxin in the early 1970s is identified with initiatives of Dr. Steinetz, and there is now a sufficient body of knowledge to warrant its integration into general endocrinology. A documentation of the reasons for the neglect of relaxin would make an interesting exercise in the history of endocrinology but is outside the scope of this review. I mention my perceptions below because they may become applicable to other fields of endeavor in endocrinology as reductions in Federal funding for research encourage scientists to look to the private sector for support.