gammaendorphin

Gamma-endorphin is an endogenous opioid peptide derived from proopiomelanocortin (POMC), the precursor that also yields ACTH and beta-endorphin. It is produced by proteolytic processing of POMC in pituitary corticotrophs and certain neurons in the brain, and is released together with other POMC-derived peptides in response to neuroendocrine signaling and stress.

Pharmacology and activity of gamma-endorphin are not as well defined as those of beta-endorphin. It is classified as an opioid peptide, but its receptor affinity and physiological potency are generally considered lower and more uncertain. Some studies have reported mu-opioid receptor activity, while others have found weak or inconsistent effects. The extent to which gamma-endorphin contributes to analgesia or other opioid-related functions remains unclear, and there is also consideration of potential non-opioid actions that do not involve classical opioid receptors.

Physiological significance of gamma-endorphin is not firmly established. Its biological relevance is explored mainly within the broader context of POMC-derived peptide processing and the regulation of the endogenous opioid system. Because of its relatively lower abundance and overlapping immunoreactivity with related fragments, precise in vivo roles are challenging to delineate.

Detection and research approaches rely on immunoassays and analytical techniques such as mass spectrometry, with attention to cross-reactivity among POMC-derived peptides. Distribution varies by tissue and species, and factors such as physiological state can influence levels. Ongoing work investigates the enzymes responsible for POMC processing and how gamma-endorphin interacts with other peptides in the opioid pathway.