Endorphins are located in the intermediate and anterior lobes of the pituitary gland, not in the neurohypophysis

Isolation and characterization of α‐endorphin and γ‐endorphin from single human pituitary glands

“…The specificity of antiserum L2 for the free COOH terminal sequence &-endorphin- (9)(10)(11)(12)(13)(14)(15)(16)(17) and the isolation of ,& endorphin-(10- 17) demonstrates that this large form contains&endorphin-(10- 17) as COOH terminal sequence. The data indicate that this component is human ,&lipotropin-( i-75).…”

Beta‐endorphin and beta‐lipotropin secretion by an acth‐secreting mouse pituitary tumor

“…Likewise, the production of immunoreactive betaendorphin by the rat transplantable pituitary tumor MtT-F4 which is known to secrete ACTH has been described [17]. Immunocytochemical studies have pointed out the presence of ACTH, beta-LPH and betaendorphin in the same cells of anterior and intermediate pituitary lobes [23,24]. The biosynthesis of a common precursor (31 K) to betaendorphin and ACTH [lo-121, as well as betaendorphin and ACTH-like peptides was demonstrated by experiments using the AtT-20/D-16V cell line [25].…”

Opioid peptides and pituitary function

“…ß-Endorphin is more restricted in its distribution with high concentrations in the anterior and intermediate lobes of the pituitary and lower concentrations in a few brain areas around the midline and in the hypothalamus, thalamus, midbrain and pons (Cox, Goldstein & Li, 1976;Bloom et al, 1977;Rossier et al, 1977c;Bloom, Battenberg, Rossier, Ling & Guillemin, 1978).…”