Author/Editor     Noristani, Harun N.; Meadows, RS; Olabarria, Markel; Verkhratsky, Alexei; Rodríguez, José J.
Title     Increased hippocampal CA1 density of serotonergic terminals in a triple transgenic mouse model of Alzheimer's disease
Type     članek
Vol. and No.     Letnik 2, št. 9
Publication year     2011
Volume     str. 1-11
ISSN     2041-4889 - Cell death & disease
Language     eng
Abstract     Alzheimer's disease (AD) is a neurodegenerative pathology that deteriorates mnesic functions and associated brain regions including the hippocampus. Serotonin (5-HT) has an important role in cognition. We recently demonstrated an increase in 5-HT transporter (SERT) fibre density in the hippocampal CA1 in an AD triple transgenic mouse model (3xTg-AD). Here, we analyse the ultrastructural localisation, distribution and numerical density (N v ) of hippocampal SERT axons (SERT-Ax) and terminals (SERT- Te) and their relationship with SERT fibre sprouting and altered synaptic N v in 3xTg-AD compared with non-transgenic control mice. 3xTg-AD animals showed a significant increase in SERT-Te N v in CA1 at both, 3 (95%) and 18 months of age (144%), being restricted to the CA1 stratum moleculare (S. Mol; 227% at 3 and 180% at 18 months). 3xTg-AD animals also exhibit reduced N v of perforated axospinous synapses (PS) in CA1 S. Mol (56% at 3 and 52% at 18 months). No changes were observed in the N v of symmetric and asymmetrical synapses or SERT-Ax. Our results suggest that concomitant SERT-Te N v increase and PS reduction in 3xTg-AD mice may act as a compensatory mechanism maintaining synaptic efficacy as a response to the AD cognitive impairment.
Keywords     Alzheimer's disease
hippocampal
serotonergic terminals
Alzheimerjeva bolezen
hipokampus
serotoninergični terminali