Cerebral blood volume estimation by ferumoxytol‐enhanced steady‐state MRI at 9.4 T reveals microvascular impact of α1‐adrenergic receptor antibodies. (24th July 2014)

• Record Type: Journal Article
• Authors: Pohlmann, Andreas; Karczewski, Peter; Ku, Min‐Chi; Dieringer, Babette; Waiczies, Helmar; Wisbrun, Natali; Kox, Stefanie; Palatnik, Irina; Reimann, Henning Matthias; Eichhorn, Christina; Waiczies, Sonia; Hempel, Petra; Lemke, Bernd; Niendorf, Thoralf; Bimmler, Marion
• Is Part Of: NMR in biomedicine. Volume 27:Number 9(2014:Sep.)
• Page Start: 1085
• Page End: 1093
• Publication Date: 2014-07-24
• Subjects: Nuclear magnetic resonance -- Periodicals; Magnetic Resonance Spectroscopy -- Periodicals; 574
• DOI: 10.1002/nbm.3160
• Languages: English
• ISSNs: 0952-3480

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <p>Cerebrovascular abnormality is frequently accompanied by cognitive dysfunctions, such as dementia. Antibodies against the α<sub>1</sub>‐adrenoceptor (α<sub>1</sub>‐AR) can be found in patients with Alzheimer's disease with cerebrovascular disease, and have been shown to affect the larger vessels of the brain in rodents. However, the impact of α<sub>1</sub>‐AR antibodies on the cerebral vasculature remains unclear. In the present study, we established a neuroimaging method to measure the relative cerebral blood volume (rCBV) in small rodents with the ultimate goal to detect changes in blood vessel density and/or vessel size induced by α<sub>1</sub>‐AR antibodies. For this purpose, mapping of <italic>R</italic><sub>2</sub>* and <italic>R</italic><sub>2</sub> was performed using MRI at 9.4 T, before and after the injection of intravascular iron oxide particles (ferumoxytol). The change in the transverse relaxation rates (Δ<italic>R</italic><sub>2</sub>*, Δ<italic>R</italic><sub>2</sub>) showed a significant rCBV decrease in the cerebrum, cortex and hippocampus of rats (except hippocampal Δ<italic>R</italic><sub>2</sub>), which was more pronounced for Δ<italic>R</italic><sub>2</sub>* than for Δ<italic>R</italic><sub>2</sub>. Immunohistological analyses confirmed that the α<sub>1</sub>‐AR antibody induced blood vessel deficiencies. Our findings support the hypothesis that α<sub>1</sub>‐AR antibodies lead to cerebral vessel damage throughout the brain, which can be monitored by MRI‐derived rCBV, a non‐invasive neuroimaging method. This demonstrates the value of rCBV estimation by ferumoxytol‐enhanced MRI at 9.4 T, and further underlines the significance of this antibody in brain diseases involving vasculature impairments, such as dementia. Copyright © 2014 John Wiley & Sons, Ltd.</p> </abstract>