Hartlage-Ruebsamen M, Lippe WR, Schliebs R (1999) Cholinergic basal forebrain lesion results in reduced activity of neuronal NO synthase in hippocampal and neocortical areas of the rat brain. Neuroscience 1999 Abstracts 847.3. Society for Neuroscience, Miami, FL.
Summary: Nitric oxide (NO) released by cortical neurons expressing the neuronal form of NO synthase (nNOS) is known to stimulate regional cerebral blood flow and is implicated in the formation of long term potentiation in the hippocampus. Cortical nNOS containing neurons express M] muscarinic acetylcholine receptors and receive cholinergic input from the basal forebrain (BF). Consequently, it has been shown that stimulation of BF cholinergic neurons leads to increased cortical perfusion. Cholinergic cell loss in the BF, reduced cortical blood flow and memory’ dysfunction are characteristics of Alzheimer’s disease. In the present study, we investigated the impact of a selective lesion of BF cholinergic neurons by the cholinergic toxin 192IgG-saporin on the expression and substrate binding activity of nNOS in selected regions of neocortex and hippocampus in the rat. While Western blot analysis yielded no significant changes in total nNOS protein levels 7 days post lesion, nNOS catalytic and substrate binding activity was reduced in a number of hippocampal and neocortical subregions as revealed by NADPH- diaphorase enzyme histochemistry and by quantitative autoradiography using [3H]L-A,’G-nitro-arginine binding. The data suggest that cholinergic mechanisms control, at least in part, neocortical and hippocampal nNOS activity providing further evidence for an NO-mediated influence of the BF cholinergic system on memory function and cortical perfusion. Contract grant sponsor: Deutsche Forschungsgemeinschaft, SCHL 363/4-1.
Related Products: 192-IgG-SAP (Cat. #IT-01)