Primary cultures of neuronal and non-neuronal rat brain cells secrete similar proportions of amyloid beta peptides ending at A beta 40 and A beta 42

To determine the types of brain cells responsible for the production of amy loid beta peptides (A beta), as well as their carboxyl-terminal properties, we studied the secretion of A beta in rat neuronal, astrocytic, microglial and meningeal primary cell cultures. All four types of cells produced A be ta, among which neurons secreted similar to 4 times more Ab than other cell types. The percentage of A beta 42 ending:at position 42 as a fraction of total A beta was similar between different cell types, ranging from 10 to 1 5%. These results suggest that neurons might be the most,:potent source for A beta production in the brain, although other non-neuronal type cells cou ld also contribute to this process. (C) 1999 Lippincott Williams & Wilkins.