Beta-amyloid (1-42) affects cholinergic but not parvalbumin-containing neurons in the septal complex of the rat.

beta-Amyloid(1-42) peptide (beta AP(1-42) was injected into the medial septum of rats. After a 14-day survival time, neuronal alterations in the septal cholinergic and GABAergic systems were visualized by means of histo- and immunocytochemical methods. Neurons insulted by the peptide were primary choline acetyltransferase-immunoreactive (ir), while only minor effects of beta AP(1-42) were observed on parvalbumin-ir interneurons. These results indicate that the changes in intracellular Ca2+ level elicited by beta AP(1-42) may contribute to beta-amyloid neurotoxicity, and Ca(2+)-binding proteins may play an important role in the protection against the neurotoxic effects of beta AP(1-42).