obestatin A peptide hormone derived from a prohormone, preproghrelin—which also contains ghrelin—by post-translational processing, originating from endocrine cells in the stomach. Obestatin is encoded by GHRL on chromosome 3p26-p25. The ratio of obestatin and ghrelin is altered in obesity and in anorexia nervosa. Initially reported as an anorexigenic hormone, recent data suggest that obestatin inhibits thirst and anxiety, improves memory, regulates sleep, affects cell proliferation, and increases secretion of the exocrine pancreas. Antisense transcripts for GHRL have been identified which regulate ghrelin-obestatin preproprotein expression.