A new neuronal target for beta-amyloid peptide in the rat hippocampus

作者：Villette Vincent; Poindessous Jazat Frederique; Bellessort Brice; Roullot Elodie; Peterschmitt Yvan; Epelbaum Jacques; Stephan Aline; Dutar Patrick^*

来源：Neurobiology of Aging, 2012, 33(6): 1126.e1.

DOI：10.1016/j.neurobiolaging.2011.11.024

• Septohippocampal network
• Hippocamposeptal neurons
• Calbindin
• Somatostatin
• Theta oscillation
• Alzheimer%26apos
• s disease
• Rat model

In Alzheimer%26apos;s disease, amyloid beta peptide (A beta) accumulation is associated with hippocampal network dysfunction. Intrahippocampal injections of A beta induce aberrant inhibitory septohippocampal (SH) network activity in vivo and impairment of memory processing. In the present study, we observed, after hippocampal A beta treatment, a selective loss of neurons projecting to the medial septum (MS) and containing calbindin (CB) and/or somatostatin (SOM). Other GABAergic neuronal subpopulations were not altered. Thus, the present study identifies hippocamposeptal neuron populations as specific targets for A beta deposits. We observed that in A beta-treated rats but not in controls, glutamate agonist application induced rhythmic bursting in 55% of the slow-firing neurons in the medial septum. This suggests that hippocampal A beta can trigger modifications of the septohippocampal pathway via the alteration of a specific neuronal population. Long-range hippocamposeptal GABA/calbindin neurons, targets of hippocampal amyloid deposits, are implicated in supporting network synchronization. By identifying this target, we contribute to the understanding of the mechanisms underlying deleterious effects of A beta, one of the main agents of dementia in Alzheimer%26apos;s disease.

• 出版日期2012-6