relatively high concentrations of ir-alpha-neo-endorphin ( 250 to 500 fmol/mg of protein ) are present in the bed nucleus of the stria terminalis , paraventricular nucleus , nucleus of the solitary tract , dorsomedial nucleus , central amygdaloid nucleus , periaqueductal gray matter , suprachiasmatic nucleus , periventricular nucleus , hippocampus , prepositus hypoglossal nucleus , arcuate nucleus , ventromedial nucleus , medial preoptic nucleus , zona incerta , dorsal premamillary nucleus , medial forebrain bundle ( hypothalamic and preoptic ) , nucleus of the diagonal band , locus ceruleus , lateral septal nucleus , and nucleus ambiguus . moderate levels ( 100 to 250 fmol/mg of protein ) are found in the posterior hypothalamic nucleus , ventral premamillary nucleus , dorsal raphe nucleus , motor hypoglossal nucleus , caudate-putamen , periventricular thalamic nucleus , subcommissural organ , sensory trigeminal nucleus , perifornical nucleus , area postrema , supraoptic nucleus , cuneate nucleus , medial amygdaloid nucleus , and organum vasculosum laminae terminalis .
C0038866
suprachiasmatic nucleus
C0020663
hypothalamic