We evaluated the CSF levels of β-lipotropin (β-LPH), β-endorphin (β-EP) and ACTH, which are three neuropeptides expressed by the same gene encoding for pro-opiomelanocortin, in various groups of demented patients including degenerative (presenile and senile Alzheimer-type dementia, ATD) and vascular (MID) forms. Twelve sex- and age-matched subjects were taken as controls. Our data indicate that ACTH levels are significantly reduced both in ATD and MID patients, while P-EP and P-LPH are significantly reduced only in ATD. The low CSF ACTH levels can be considered typical of all demented processes (both degenerative and vascular), while the reduction of β-EP and β-LPH in CSF could be due to a degenerative process o