Fragment 176-191 — 5 mg

Fragment 176-191 refers to a sixteen-residue segment near the end of human growth hormone, rather than the complete 191-residue hormone. Umbrella Labs positions it as a research material related to the fat-metabolism effects of growth hormone and explicitly identifies AOD-9604 as a closely related modified form. Its description associates this research area with reduced fat accumulation and an absence of the IGF-1 response ordinarily discussed for full-length growth hormone.

The primary literature needs to be read by compound identity. Wu and Ng investigated the neighboring 177–191 fragment and reported inhibition of lipid synthesis in experimental rat tissues, without a significant increase in their glycerol-release measure of fat breakdown. Separate work by Heffernan and colleagues studied AOD-9604 in obese mice and described changes in body fat, fat oxidation and beta-adrenergic signaling. These papers help explain the commercial focus on lipid metabolism, but they do not make every growth-hormone tail fragment the same molecule. A research description should therefore preserve the distinction between unmodified 176–191, 177–191 and the modified analogue AOD-9604 instead of merging their results under one product name.