Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5491418 | Magnetic Resonance Imaging | 2017 | 12 Pages |
Abstract
Manganese-enhanced magnetic resonance imaging (MEMRI) offers unique advantages such as studying brain activation in freely moving rats, but its usefulness has not been previously evaluated during operant behavior training. Manganese in a form of MnCl2, at a dose of 20Â mg/kg, was intraperitoneally infused. The administration was repeated and separated by 24Â h to reach the dose of 40Â mg/kg or 60Â mg/kg, respectively. Hepatotoxicity of the MnCl2 was evaluated by determining serum aspartate aminotransferase, alanine aminotransferase, total bilirubin, albumin and protein levels. Neurological examination was also carried out. The animals were tested in visual cue discriminated operant task. Imaging was performed using a 3T clinical MR scanner. T1 values were determined before and after MnCl2 administrations. Manganese-enhanced images of each animal were subtracted from their baseline images to calculate decrease in the T1 value (ÎT1) voxel by voxel. The subtracted T1 maps of trained animals performing visual cue discriminated operant task, and those of naive rats were compared. The dose of 60Â mg/kg MnCl2 showed hepatotoxic effect, but even these animals did not exhibit neurological symptoms. The dose of 20 and 40Â mg/kg MnCl2 increased the number of omissions and did not affect the accuracy of performing the visual cue discriminated operant task. Using the accumulated dose of 40Â mg/kg, voxels with a significant enhanced ÎT1 value were detected in the following brain areas of the visual cue discriminated operant behavior performed animals compared to those in the controls: the visual, somatosensory, motor and premotor cortices, the insula, cingulate, ectorhinal, entorhinal, perirhinal and piriform cortices, hippocampus, amygdala with amygdalohippocampal areas, dorsal striatum, nucleus accumbens core, substantia nigra, and retrorubral field. In conclusion, the MEMRI proved to be a reliable method to accomplish brain activity mapping in correlation with the operant behavior of freely moving rodents.
Keywords
ALTPTAMEAaHIVPMRSARRFPRHVPLENTRSGICJectorhinal cortexretrosplenial agranular cortexECTCPUAcbASTAspartate aminotransferaseAlanine aminotransferaseAmygdalaAMYPirsubstantia nigraOlfactory tubercleislands of Callejaretrorubral fieldSubiculumTemporal association cortexprimary somatosensory cortexEntorhinal cortexprimary motor cortexsecondary motor cortexretrosplenial granular cortexRetrosplenial cortexAgranular insular cortexGranular insular cortexdysgranular insular cortexAuditory Cortexperirhinal cortexpiriform cortexSecondary somatosensory cortexHIPamygdalohippocampal areaNucleus accumbensVentral posteromedial thalamic nucleusventral posterolateral thalamic nucleusHypothalamusHippocampusTEAparietal association cortexcingulate cortexPitGlobus pallidus
Related Topics
Physical Sciences and Engineering
Physics and Astronomy
Condensed Matter Physics
Authors
Rita Gálosi, Csaba Szalay, Mihály Aradi, Gábor Perlaki, József Pál, Roy Steier, László Lénárd, Zoltán Karádi,