fl-Amyloid(1_42 ) affects cholinergic but not parvalbumin-containing neurons in the septal complex of the rat

fl-Amyloido 42) peptide ( flAP 0 _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 histoand immunocytochemical methods. Neurons insulted by the peptide were primarily choline acetyltransferase-immunoreactive (ir), while only minor effects of flAP~v4: ) were observed on parvalbumin-ir interneurons. These results indicate that the changes in intracellular Ca 2+ level elicited by flAP(l_42 ) may contribute to /3-amyloid neurotoxicity, and Ca2+-binding proteins may play an important role in the protection against the neurotoxic effects of ~AP, 421.