Beta-cell tropin: synthesis and biological activity.

The structure of beta-cell tropin, an insulin secretagogue released by the neuro-intermediate lobe of the obese (ob/ob) mouse, has recently been determined as the 22-39 moiety of ACTH. A method for the preparation of this octadecapeptide using mild solid-phase procedures followed by preparative high pressure liquid chromatography is described. The molecular weight of the synthetic peptide has been confirmed by Fast Atom Bombardment mass spectrometry. Synthetic beta-cell tropin is indistinguishable in its chromatographic, antigenic and biological properties from natural beta-cell tropin.