Figure 1. Brain localization of Aβ_25–35 and particle characterization of Aβ_25–35 solutions A–I.

Localization within brain structures of oAβ_25–35-HLF, determined 6 weeks after its icv injection (10 µg/rat). oAβ_25–35-HLF was visualized in green, while the nucleus was counterstained with DAPI (blue labeling). Abbreviations: 3V: third ventricle; alv: alveus of the hippocampus; CA1: field CA1 of hippocampus; CA3: field CA3 of the hippocampus; cc: corpus callosum; D3V: dorsal third ventricle; ec: external capsule; fi: fimbria of the hippocampus; FrA: frontal association cortex; hf: hippocampal fissure; LV: lateral ventricle; MEE: median eminence, external part; MEI: median eminence, internal part; MHb: medial habenular nucleus; PVN: paraventricular hypothalamic nucleus; PVP: paraventricular thalamic nucleus, posterior part. Arrowhead: blood vessel. Scale bar  = 100 µm. J. Particle size distribution of the different fractions of Aβ_25–35 solution (1 µg/µl) was determined by PCS at 25°C. Samples were prepared as described in the materials and methods section. Black curve: Aβ_25–35 peptide dissolved in hexafluoroisopropanol (HFIP); Red curve: solution of aggregated Aβ_25–35 peptide; Green curve: supernatant of aggregated Aβ_25–35 peptide centrifuged at 1 000 g; Purple curve: re-suspended pellet of aggregated Aβ_25–35 peptide obtained after centrifugation at 1 000 g; Blue curve: supernatant of aggregated Aβ_25–35 peptide centrifuged at 16 000 g. Data were analyzed using a Zetasizer software 6.01 and expressed as size frequency distribution (%) in function of particles size (nm).