MRI of Animal Models of Brain Disease

Abstract

This chapter elaborates the magnetic resonance imaging (MRI) of animal models of brain disease. The utility of MRI with respect to animal models of disease lies in the sensitivity of the technique to both microscopic and macroscopic molecular motions. In arterial spin labeling, perfusion-weighted images are generated by labeling in flowing blood water by inversion of its longitudinal magnetization. Two images must be acquired, including the labeled image and the control image. The difference between the two images is proportional to the amount of labeled blood that enters the imaging slice during the time between labeling and image acquisition, and therefore, is also proportional to cerebral blood flow. It is found that as blood oxygenation level dependent (BOLD) MRI is sensitive to changes in regional tissue oxygenation status, it can be used to monitor acute deoxygenation following induction of ischemia, as well as reoxygenation after reperfusion. BOLD MR signal intensity drops immediately upon the onset of ischemia and rises when reflow occurs. The experimental models are based on the acute lesioning using GABAergic antagonists or chronic lesioning using systemic administration of 3-nitroproprionic acid are also elaborated.