Abstract
In aged cats, light microscopic studies revealed significant decrease in the soma size of choline acetyltransferase (ChAT)-positive neurons in the laterodorsal and pedunculo-pontine tegmental nuclei (LDT and PPT), compared with adult control animals. In addition, a significant reduction of the total dendritic length and total dendritic segment number of ChAT-positive neurons was detected in both the LDT and PPT of aged cats. However, in contrast to the changes of soma and dendrites, no significant changes in the number of ChAT-positive neurons in aged were found comparing to that in the control cats in both the LDT and PPT; nor were there differences in the staining intensity of the somata of neurons in the adult and aged cats. Electron microscopic analysis highlighted degenerative changes in cholinergic neurons in the LDT and PPT of aged cats which included somata with intracytoplasmic vacuoles, darkened mitochondria, depletion of dendritic microtubules and severe demyelination of axons. These data indicate that profound atrophic changes occur in cholinergic systems of the LDT and PPT as a consequence of the aging process. These alterations likely reflect the cellular bases for the age-related changes in REM sleep that occur in old animals.
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.