title: Application of a compact magnetic resonance imaging system for toxicologic pathology: evaluation of lithium-pilocarpine-induced rat brain lesions.
abstract: Magnetic resonance imaging (MRI) is a useful noninvasive tool used to detect lesions in clinical and veterinary medicine. The present study evaluated the suitability of a new easy-to-use compact MRI platform (M2 permanent magnet system, Aspect Imaging, Shoham, Israel) for assisting with preclinical toxicologic pathology examination of lesions in the rat brain. In order to induce brain lesions, male Sprague-Dawley rats were treated once with lithium chloride (127 mg/kg, intraperitoneal [i.p.]) followed by pilocarpine (30 mg/kg, i.p.). One week after dosing, the perfused, fixed brains were collected, analyzed by the MRI system and examined histopathologically. MRI of the brain of treated rats revealed areas of high T1 and middle to low T2 signals, when compared with the controls, in the piriform cortex, lateral thalamic nucleus, posterior paraventricular thalamic nucleus and posterior hypothalamic nucleus of the cerebrum. The altered MRI signal areas were consistent with well-circumscribed foci of neuronal cell degeneration/necrosis accompanied by glial cell proliferation. The present data demonstrated that quick analysis of fixed organs by the MRI system can detect the presence and location of toxicologic lesions and provide useful temporal information for selection of appropriate sections for histopathologic examination before routine slide preparation, especially in complex and functionally heterogeneous organs such as the brain.
authors.affiliation: Tsukuba Drug Safety, Global Drug Safety, Biopharmaceutical Assessments Core Function Unit, Eisai Product Creation Systems, Eisai Co., Ltd., 5-1-3 Tokodai, Tsukuba, Ibaraki 300-2635, Japan.
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Taketa
authors.affiliation: Tsukuba Drug Safety, Global Drug Safety, Biopharmaceutical Assessments Core Function Unit, Eisai Product Creation Systems, Eisai Co., Ltd., 5-1-3 Tokodai, Tsukuba, Ibaraki 300-2635, Japan.
authors.forename: Motohiro
authors.initials: M
authors.lastname: Shiotani
authors.affiliation: Research Support Department, Primetech Corp., 1-3-25 Koishikawa, Bunkyo-ku, Tokyo 112-0002, Japan.
authors.forename: Yoshiharu
authors.initials: Y
authors.lastname: Tsuru
authors.affiliation: Neuroscience and General Medicine Product Creation Unit, Eisai Product Creation Systems, Eisai Co., Ltd., 5-1-3 Tokodai, Tsukuba, Ibaraki 300-2635, Japan.
authors.forename: Sadaharu
authors.initials: S
authors.lastname: Kotani
authors.affiliation: Neuroscience and General Medicine Product Creation Unit, Eisai Product Creation Systems, Eisai Co., Ltd., 5-1-3 Tokodai, Tsukuba, Ibaraki 300-2635, Japan.
authors.forename: Yoshihide
authors.initials: Y
authors.lastname: Osada
authors.affiliation: Neuroscience and General Medicine Product Creation Unit, Eisai Product Creation Systems, Eisai Co., Ltd., 5-1-3 Tokodai, Tsukuba, Ibaraki 300-2635, Japan.
authors.forename: Tatsuto
authors.initials: T
authors.lastname: Fukushima
authors.affiliation: Tsukuba Drug Safety, Global Drug Safety, Biopharmaceutical Assessments Core Function Unit, Eisai Product Creation Systems, Eisai Co., Ltd., 5-1-3 Tokodai, Tsukuba, Ibaraki 300-2635, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Inomata
authors.affiliation: Tsukuba Drug Safety, Global Drug Safety, Biopharmaceutical Assessments Core Function Unit, Eisai Product Creation Systems, Eisai Co., Ltd., 5-1-3 Tokodai, Tsukuba, Ibaraki 300-2635, Japan.
authors.forename: Satoru
authors.initials: S
authors.lastname: Hosokawa
keywords: magnetic resonance imaging; neuronal cell degeneration; pilocarpine; rat