Effects of aging on the cholinergic innervation of the rat ventral tegmental area: A stereological study

• Type: Article in International Scientific Journal
• Date: 2021

Authors

Pereira, PA (Author) FMUP; Hespanhol V (Author) FMUP; Silva, A (Author) Other; Madeira, MD (Author) FMUP

Journal

Title: Experimental Gerontology

Vol. 148

ISSN: 0531-5565

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 3 Citations

Scopus - 3 Citations

Other information

Authenticus ID: P-00T-KWN

DOI: 10.1016/j.exger.2021.111298

Abstract (EN): Dopamine neurons in the ventral tegmental area (VTA) play a main role in processing both rewarding and aversive stimuli, and their response to salient stimuli is significantly shaped by afferents originating in the brainstem cholinergic nuclei. Aging is associated with a decline in dopaminergic activity and reduced response to positive reinforcement. We have used stereological techniques to examine, in adult and aged rats, the dopaminergic neurons and the cholinergic innervation of the VTA, and the cholinergic populations of the pedunculopontine tegmental (PPT) and laterodorsal tegmental (LDT) nuclei, which are the only source of cholinergic inputs to the VTA. In the VTA, there were no age-related variations in the number and size of tyrosine hydroxylase (TH)immunoreactive neurons, but the density of cholinergic varicosities was reduced in aged rats. The total number of choline acetyltransferase (ChAT)-immunoreactive neurons in the PPT and LDT was unchanged, but their somas were hypertrophied in aged rats. Our results suggest that dysfunction of the cholinergic system might contribute for the age-associated deterioration of the brain reward system.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10