Abstract
This study aimed to evaluate the T2 relaxation time of the brain in severely scalded rats using a magnetic resonance (MR) T2 mapping sequence, and to investigate the correlation between T2 relaxation time and plasma glucose level. Twenty-eight Wistar rats were randomly divided into the scalded group (n=21) and control group (n=7). Magnetic resonance scans were performed with T1WI, T2WI, and T2-mapping sequences in the scalded group; the scans were performed 1 day prior to scalding and 1, 3, 5, and 7 days post-scalding; in addition, identical MR scans were performed in the control group at the same time points. T2-maps were generated and T2 relaxation times were acquired from the following brain regions: the hippocampus, thalamus, caudate-putamen, and cerebrum. Pathological changes of the hippocampus were observed. The plasma glucose level of each rat was measured before each MR scan, and a correlation analysis was performed between T2 relaxation time and plasma glucose level. We found that conventional T1WI and T2WI did not reveal any abnormal signals or morphological changes in the hippocampus, thalamus, caudate-putamen, or cerebrum post-scalding. Both the T2 relaxation times of the selected brain regions and plasma glucose levels increased 1, 3, and 5 days post-scalding, and returned to normal levels 7 days post-scalding. The most marked increase of T2 relaxation time was found in the hippocampus; similar changes were also revealed in the thalamus, caudate-putamen, and cerebrum. No correlation was found between T2 relaxation time and plasma glucose level in scalded rats. Pathological observation of the hippocampus showed edema 1, 3, and 5 days post-scalding, with recovery to normal findings at 7 days post-scalding. Thus, we concluded that T2 mapping is a sensitive method for detecting and monitoring scald injury in the rat brain. As the hippocampus is the main region for modulating a stress reaction, it showed significantly increased water content along with an increased plasma glucose level post-scalding.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Bederson, J.B., Bartkowski, H.M., Moon, K., Halks-Miller, M., Nishimura, M.C., Brant-Zawadski, M., and Pitts, L.H. (1986). Nuclear magnetic resonance imaging and spectroscopy in experimental brain edema in a rat model. J Neurosurgery 64, 795–802.
Cherian, L., Goodman, J.C., and Robertson, C.S. (1997). Hyperglycemia increases brain injury caused by secondary ischemia after cortical impact injury in rats. Crit Care Med 25, 1378–1383.
Cherian, L., Hannay, H.J., Vagner, G., Goodman, J.C., Contant, C.F., and Robertson, C.S. (1998). Hyperglycemia increases neurological damage and behavioral deficits from post-traumatic secondary ischeie insults. J Neurotrauma 15, 307–321.
Choi, K.T., Illievich, U.M., Zornow, M.H., Scheller, M.S., and Strnat, M.A. (1994). Effect of hyperglycemia on peri-ischemic neurotransmitter levels in the rabbit hippocampus. Brain Res 642, 104–110.
de Kloet, E.R., Vreugdenhil, E., Oitzl, M.S., and Joëls, M. (1998). Brain corticosteroid receptor balance in health and disease. Endocr Rev 19, 269–301.
Duncan, J.S., Bartlett, P., and Barker, G.J. (1996). Technique for measuring hippocampal T2 relaxation time. AJNR Am J Neuroradiol 17, 1805–1810.
Haitao, L., Dajun, Y., Kaifa, W., Xiuwu, B., Jiansen, S., and Zongchen, Y. (2005). Application of a four-dimensional mathematical model in the establishment of an early post-burn cerebral oedema model in severely burned dogs. Ann Burns Fire Disasters 18, 95–99.
Hoehn-Berlage, M., and Bockhorst, K. (1994). Quantitative magnetic resonance imaging of rat brain tumors: in vivo NMR relaxometry for the discrimination of normal and pathological tissues. Technol Health Care 2, 247–254.
Huang, C.W., Cheng, J.T., Tsai, J.J., Wu, S.N., and Huang, C.C. (2009). Diabetic hyperglycemia aggravates seizures and status epilepticus-induced hippocampal damage. Neurotox Res 15, 71–81.
Izamis, M.L., Sharma, N.S., Uygun, B., Bieganski, R., Saeidi, N., Nahmias, Y., Uygun, K., Yarmush, M.L., and Berthiaume, F. (2011). In situ metabolic flux analysis to quantify the liver metabolic response to experimental burn injury. Biotechnol Bioeng 108, 839–852.
Jayakumar, P.N., Srikanth, S.G., Chandrashekar, H.S., and Subbakrishna, D.K. (2007). T2 relaxometry of ring lesions of the brain. Clin Radiol 62, 370–375.
Jeremitsky, E., Omert, L.A., Dunham, C.M., Wilberger, J., and Rodriguez, A. (2005). The impact of hyperglycemia on patients with severe brain injury. J Trauma 58, 47–50.
Korte, S.M. (2001). Corticosteroids in relation to fear, anxiety and psychopathology. Neurosci Biobehav Rev 25, 117–142.
Li, H., Ying, D., Sun, J., Bian, X., Zhang, Y., and He, B. (2001). Comparative observation with MRI and pathology of brain edema at the early stage of severe burn. Chin J Traumatol 4, 226–230.
Li, H., Ying, D., He, X., Sun, J., and Chen, L. (2009). Stereoscopic study on capillary density of early brain oedema in a dog postburn model. Injury 40, 835–839.
Li, P.A., Shuaib, A., Miyashita, H., He, Q.P., Siesjo, B.K., and Warner, D.S. (2000). Hyperglycemia enhances extracellular glutamate accumulation in rats subjected to forebrain ischemia editorial comment. Stroke 31, 183–192.
Li, Y.P. (1993). Patho-morphological changes in the brain after severe burns. Zhonghua Zheng Xing Shao Shang Wai Ke Za Zhi 9, 186–188, 238.
Loubinoux, I., Volk, A., Borredon, J., Guirimand, S., Tiffon, B., Seylaz, J., Meric, P., and Rosenberg, G.A. (1997). Spreading of vasogenic edema and cytotoxic edema assessed by quantitative diffusion and T2 magnetic resonance imaging. Stroke 28, 419–427; discussion 426–417.
Magariños, A.M., Jain, K., Blount, E.D., Reagan, L., Smith, B.H., and McEwen, B.S. (2001). Peritoneal implantation of macroencapsulated porcine pancreatic islets in diabetic rats ameliorates severe hyperglycemia and prevents retraction and simplification of hippocampal dendrites. Brain Res 902, 282–287.
Mamere, A.E., Saraiva, L.A.L., Matos, A.L.M., Carneiro, A.A.O., and Santos, A.C. (2009). Evaluation of delayed neuronal and axonal damage secondary to moderate and severe traumatic brain injury using quantitative mr imaging techniques. Am J Neuroradiol 30, 947–952.
Neema, M., Goldberg-Zimring, D., Guss, Z.D., Healy, B.C., Guttmann, C.R.G., Houtchens, M.K., Weiner, H.L., Horsfield, M.A., Hackney, D.B., Alsop, D.C., and Bakshi, R. (2009). 3 T MRI relaxometry detects T2 prolongation in the cerebral normal-appearing white matter in multiple sclerosis. Neuroimage 46, 633–641.
Okujava, M., Schulz, R., Ebner, A., and Woermann, F.G. (2002). Measurement of temporal lobe T2 relaxation times using a routine diagnostic MR imaging protocol in epilepsy. Epilepsy Res 48, 131–142.
Pulsinelli, W.A., Waldman, S., Rawlinson, D., and Plum, F. (1982). Moderate hyperglycemia augments ischemic brain damage: a neuropathologic study in the rat. Neurology 32, 1239–1239.
Reyes, R., Guo, M., Swann, K., Shetgeri, S.U., Sprague, S.M., Jimenez, D.F., Barone, C.M., and Ding, Y. (2009). Role of tumor necrosis factoralpha and matrix metalloproteinase-9 in blood-brain barrier disruption after peripheral thermal injury in rats. J Neurosurg 110, 1218–1226.
Singhal, A., Nagarajan, R., Kumar, R., Huda, A., Gupta, R.K., and Thomas, M.A. (2009). Magnetic resonance T2-relaxometry and 2D L-correlated spectroscopy in patients with minimal hepatic encephalopathy. J Magn Reson Imaging 30, 1034–1041.
Swann, K., Berger, J., Sprague, S.M., Wu, Y., Lai, Q., Jimenez, D.F., Barone, C.M., and Ding, Y. (2007). Peripheral thermal injury causes blood-brain barrier dysfunction and matrix metalloproteinase (MMP) expression in rat. Brain Res 1129, 26–33.
Wang, Q., Ishikawa, T., Michiue, T., Zhu, B.L., Guan, D.W., and Maeda, H. (2013). Molecular pathology of brain edema after severe burns in forensic autopsy cases with special regard to the importance of reference gene selection. Int J Legal Med 127, 881–889.
Woo, M.A., Kumar, R., Macey, P.M., Fonarow, G.C., and Harper, R.M. (2009). Brain injury in autonomic, emotional, and cognitive regulatory areas in patients with heart failure. J Cardiac Failure 15, 214–223.
Zhang, Q., Carter, E.A., Ma, B., Fischman, A.J., and Tompkins, R.G. (2008). Burn-related metabolic and signaling changes in rat brain. J Burn Care Res 29, 346–352.
Zhao, K., Wang, C.Y., Hu, J., Yang, X.D., Wang, H., Li, F.Y., Zhang, X.D., Zhang, J., and Wang, X.Y. (2015). Prostate cancer identification: quantitative analysis of T2-weighted MR images based on a back propagation artificial neural network model. Sci China Life Sci 58, 666–673.
Acknowledgements
We thank Yingkui Zhang from GE Healthcare for setting up the MRI device.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Jiang, T., Xie, L., Lou, X. et al. T2 relaxation time measurements in the brains of scalded rats. Sci. China Life Sci. 60, 5–10 (2017). https://doi.org/10.1007/s11427-016-0382-7
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11427-016-0382-7