Table of Contents
ISRN Anesthesiology
Volume 2012 (2012), Article ID 261640, 11 pages
http://dx.doi.org/10.5402/2012/261640
Research Article

MicroPET/CT Imaging of [18F]-FEPPA in the Nonhuman Primate: A Potential Biomarker of Pathogenic Processes Associated with Anesthetic-Induced Neurotoxicity

1National Center for Toxicological Research, US Food and Drug Administration, Jefferson, AR 72079, USA
23D Imaging, LLC, Little Rock, AR 72113, USA
3University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA

Received 6 August 2012; Accepted 15 September 2012

Academic Editors: J. Abraini and J.-H. Baumert

Copyright © 2012 Xuan Zhang et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Background. The inhalation anesthetics nitrous oxide (N2O) and isoflurane (ISO) are used in surgical procedures for human infants. Injury to the central nervous system is often accompanied by localization of activated microglia or astrocytosis at the site of injury. The tracer that targets to the peripheral benzodiazepine receptor (PBR), [18F]N-2-(2-fluoroethoxy)benzyl)-N-(4-phenoxypyridin-3-yl)acetamide ([18F]-FEPPA), has been reported as a sensitive biomarker for the detection of neuronal damage/inflammation. Methods. On postnatal day (PND) 5 or 6 rhesus monkey neonates were exposed to a mixture of N2O/oxygen and ISO for 8 hours and control monkeys were exposed to room air. MicroPET/CT images with [18F]-FEPPA were obtained for each monkey 1 day, one week, three weeks, and 6 months after the anesthetic exposure. Results. The radiotracer quickly distributed into the brains of both treated and control monkeys on all scan days. One day after anesthetic exposure, the uptake of [18F]-FEPPA was significantly increased in the temporal lobe. One week after exposure, the uptake of [18F]-FEPPA in the frontal lobe of treated animals was significantly greater than that in controls. Conclusions. These findings suggest that microPET imaging is capable of dynamic detection of inhaled anesthetic-induced brain damage in different brain regions of the nonhuman primate.