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 primarily 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 Ca2+-binding proteins may play an important role in the protection against the neurotoxic effects of beta AP((1-42)).