Abstract
We have previously shown that amyloid β-protein (Aβ) inhibits axonal transport via actin aggregation. In the present study, we determined the effects of angiotensin II (Ang II) on axonal transport and whether Ang II enhances the effects of Aβ. Axonal transport of neurites in cultured rat hippocampal neurons was investigated using video-microscopy. Application of Ang II decreased axonal transport of organelles. We also found that Ang II reduced the neurite diameter. These effects were mimicked by the angiotensin AT1 receptor agonist L-162,313. Aggregation of actin filaments were frequently observed in Ang II-treated neurons, and the effects of Ang II were blocked by the actin filament depolymerizer latrunculin B. These effects of Ang II were similar to those of Aβ, and the impairment of axonal transport by Aβ was enhanced by Ang II. The present in vitro study suggests that the neurotoxicity of Aβ is enhanced by Ang II through intracellular actin transformation. Angiotensin II may be involved in the progression of Alzheimer's disease. [J Physiol Sci. 2007;57 Suppl:S130]
