title: Why does MTR change with neuronal depolarization?
abstract: T1 and T2 relaxation, and magnetization transfer (MT) of the rat brain were measured during experimentally induced spreading depression (SD). All measured MR parameters changed during SD: T1 relaxation increased by approximately 13%, whereas the T2 increase was substantially larger (88%). MT results showed an MT ratio (MTR) decrease of 9%. The lack of change in the MT exchange rate indicated that the MT processes between water and macromolecular protons are not affected by neuronal depolarization. The observed decrease in MTR was only caused by changes in T1 and T2 relaxation.
authors.affiliation: Department of Medical Biophysics, Sunnybrook and Women's College Health Sciences Center, University of Toronto, Toronto, Canada. stanisz@srcl.sunnybrook.utoronto.ca
authors.forename: Greg J
authors.initials: GJ
authors.lastname: Stanisz
authors.forename: Richard S
authors.initials: RS
authors.lastname: Yoon
authors.forename: Michael L G
authors.initials: ML
authors.lastname: Joy
authors.forename: R Mark
authors.initials: RM
authors.lastname: Henkelman
mesh_terms: D000818:Animals; D013181:Cortical Spreading Depression / Q000502:physiology*; D016018:Least-Squares Analysis; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D011189:Potassium Chloride / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D015203:Reproducibility of Results
chemical_list: D011189:Potassium Chloride