| First Author | Hammerschmidt T | Year | 2013 |
| Journal | Biol Psychiatry | Volume | 73 |
| Issue | 5 | Pages | 454-63 |
| PubMed ID | 22883210 | Mgi Jnum | J:283334 |
| Mgi Id | MGI:6386107 | Doi | 10.1016/j.biopsych.2012.06.013 |
| Citation | Hammerschmidt T, et al. (2013) Selective loss of noradrenaline exacerbates early cognitive dysfunction and synaptic deficits in APP/PS1 mice. Biol Psychiatry 73(5):454-63 |
| abstractText | BACKGROUND: Degeneration of the locus coeruleus (LC), the major noradrenergic nucleus in the brain, occurs early and is ubiquitous in Alzheimer's disease (AD). Experimental lesions to the LC exacerbate AD-like neuropathology and cognitive deficits in several transgenic mouse models of AD. Because the LC contains multiple neuromodulators known to affect amyloid beta toxicity and cognitive function, the specific role of noradrenaline (NA) in AD is not well understood. METHODS: To determine the consequences of selective NA deficiency in an AD mouse model, we crossed dopamine beta-hydroxylase (DBH) knockout mice with amyloid precursor protein (APP)/presenilin-1 (PS1) mice overexpressing mutant APP and PS1. Dopamine beta-hydroxylase (-/-) mice are unable to synthesize NA but otherwise have normal LC neurons and co-transmitters. Spatial memory, hippocampal long-term potentiation, and synaptic protein levels were assessed. RESULTS: The modest impairments in spatial memory and hippocampal long-term potentiation displayed by young APP/PS1 or DBH (-/-) single mutant mice were augmented in DBH (-/-)/APP/PS1 double mutant mice. Deficits were associated with reduced levels of total calcium/calmodulin-dependent protein kinase II and N-methyl-D-aspartate receptor 2A and increased N-methyl-D-aspartate receptor 2B levels and were independent of amyloid beta accumulation. Spatial memory performance was partly improved by treatment with the NA precursor drug L-threo-dihydroxyphenylserine. CONCLUSIONS: These results indicate that early LC degeneration and subsequent NA deficiency in AD may contribute to cognitive deficits via altered levels of calcium/calmodulin-dependent protein kinase II and N-methyl-D-aspartate receptors and suggest that NA supplementation could be beneficial in early AD. |
