Why does MTR change with neuronal depolarization?
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.
Stanisz
Greg J
GJ
Department of Medical Biophysics, Sunnybrook and Women's College Health Sciences Center, University of Toronto, Toronto, Canada. stanisz@srcl.sunnybrook.utoronto.ca
Yoon
Richard S
RS
Joy
Michael L G
ML
Henkelman
R Mark
RM
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
D011189:Potassium Chloride