Imaging Core:

The development of imaging technology for animal models and sophisticated neuroanatomical approaches provide powerful means to identify specific neurocircuits that are activated by excessive consumption in animals. Most noninvasive functional imaging studies to date in humans and animals have investigated the acute and chronic effects of alcohol on local cerebral metabolism or regional cerebral blood flow to establish detailed neuroanatomical patterns of changes in functional activity throughout the brain. To study the neuroadaptive changes associated with excessive alcohol consumption, longitudinal studies following chronic ingestion are needed to distinguish acute withdrawal-related changes in brain metabolism from protracted abstinence from irreversible changes. In addition, such approaches allow one to determine the effects of abstinence on recovery of brain metabolic function.

The integration of behavioral measures with these imaging studies could reveal neural circuits associated with alcohol-related neuroadaptive phenomena that are most likely to be involved in excessive consumption, and thus, functional imaging technologies have great promise for alcohol research in bridging the gap between brain chemistry and behavior.

Magnetic Resonance Imaging (MRI) is using important modality for noninvasive imaging in animal studies of acute and chronic alcohol effects. INIA will use conventional MRI, which yields high resolution images of all brain structures, diffusion tensor imaging (DTI) and MR spectroscopy (MRS), and spectroscopic imaging (MRSI). Structural MRI can be used for highly detailed tracking of brain tissue loss and recovery over the course of alcohol exposure and withdrawal. DTI can provide quantitative data on diffusivity and coherence of highly structured tissue such as white matter. MRS and MRSI can provide information about underlying chemical composition of the imaged tissue. MR spectroscopy can provide information about the integrity of neuronal tissue with the determination of brain tissue concentrations of the neuronal marker, N-acetyl-aspartate (NAA) and the presence of gliosis with determination of concentrations of myo-inositol (mI). In addition, MR spectroscopy can also be used to determine the brain concentration of alcohol in vivo and MR spectroscopy can be employed in both single voxel and imaging modalities, the latter providing information about the spatial distribution of certain metabolites. Development of imaging technologies for rodents would be more amenable to studying neuroadaptive changes in the same animal with repeated exposure than 2- deoxyglucose techniques, and would allow integration of genetic/neuroadaptive models of excessive alcohol consumption and imaging techniques.

Robert Wind, Ph.D., a staff scientist at Pacific Northwest National Laboratory (PNNL) with an expertise in MR physics and hardware design will work closely with Portland scientists, especially after the opening of the Advanced Research Imaging Center at OHSU, to develop MR based protocols for the investigation of the circuits associated with excessive and uncontrolled drinking. He has recently designed a confocal/MR microscope for which he has received national recognition.

INIA Home   INIA Structure   Administrative Core
Genetic Animal Models Core   Gene Expression Core   Imaging Core   Neuroinformatics Core
Subgroups   Current Grants   Conference Abstracts   Publications   Links