Abstract
The nuclear complex of the horizontal limb of the diagonal band and the magnocellular preoptic nucleus, components of the basal forebrain magnocellular system affected in Alzheimer-type dementia, supply centrifugal innervation to the olfactory bulb. The lateral magnocellular preoptic nucleus provides significant GABAergic input. Since its stimulation may facilitate olfactory bulb mitral cells, we have investigated the effect of sub-total electrolytic lesions in this nucleus on performance in a simple test of olfactory investigation and its habituation. Two groups of rats were used with lesions which occupied restricted volumes, approximately 30 and 15%, of the magnocellular preoptic nucleus. Behaviourally, there was interference with olfactory investigation, with increased investigation latency and decreased investigation times, in the group with larger lesions at 6 and 16 days after operation. There was no significant effect of the smaller lesions. No effects on patterns of olfactory habituation or discrimination were seen. The impairment of olfactory investigation could not be explained by interruption of medial forebrain bundle fibres traversing the nucleus. It is suggested that bilateral partial destruction of magnocellular preoptic neurones may produce significant deficits in either olfactory sensitivity or olfactory motivation.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.