Yanai J, Rogel-Fuchs Y, Pick C G, Slotkin T, Seidler F J, Zahalka E A, Newman M E
Melvin A. and Eleanor Ross Laboratory for Studies in Neural Birth Defects, Department of Anatomy and Embryology, Hebrew University-Hadassah Medical School, Jerusalem, Israel.
Neuropharmacology. 1993 Feb;32(2):113-7. doi: 10.1016/0028-3908(93)90090-p.
Mice were injected bilaterally into the septum with 6-hydroxydopamine and 6 weeks later the hippocampi were assayed for activity of choline acetyltransferase, muscarinic receptor binding capabilities and for formation of inositol phosphate in response to direct (carbachol) or presynaptically elicited (K+) stimulation of the postsynaptic receptors. Levels of dopamine in the septum were reduced by 70% in the lesioned animals and hippocampal choline acetyltransferase was elevated by the same amount. The Bmax of muscarinic binding was significantly reduced without changes in Kd; nevertheless, carbachol-induced stimulation of formation of inositol phosphate was unaffected. The response to K+ was markedly elevated in the 6-hydroxydopamine-treated animals. Thus, the regulatory effect of A10-septal dopaminergic pathways on the septohippocampal cholinergic innervations is both on the presynaptic and postsynaptic levels.
