Mass spectrometric quantification of MIF-1 in mouse brain by multiple reaction monitoring.
MIF-1 (Pro-Leu-Gly-NH(2)) has potent therapeutic effects in depression and Parkinson's disease, but its CNS sites of production are not yet clear. In this study, the concentration of MIF-1 in different brain regions was measured by the multiple reaction monitoring technique on a 4000 QTRAP mass spectrometer. The limit of quantification was 300 fg of MIF-1, and limit of detection was 60 fg. The low molecular weight fractions of tissue homogenates from different regions of mouse brain were analyzed. The concentration of MIF-1 ranged from 22+/-3 fg/microg protein in cerebral cortex to 930+/-60 fg/microg protein in the hypothalamus. Moderate concentrations were also detected in all other regions tested, including the striatum, thalamus, and hippocampus. By incubation of stable isotope-labeled oxytocin with tissue preparations, it was also confirmed that oxytocin at least partially contributed to the production of MIF-1 in the hypothalamus by action of peptidases. Regional differences were also found. The results are the first to show the ultrasensitive quantification of MIF-1 in different brain regions, and support the neuromodulatory actions of MIF-1 in the striatum.
Kheterpal
Indu
I
Pennington Biomedical Research Center, Baton Rouge, LA 70808, USA.
Kastin
Abba J
AJ
Mollah
Sahana
S
Yu
Chuanhui
C
Hsuchou
Hung
H
Pan
Weihong
W
D000818:Animals; D001921:Brain / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D005260:Female; D007031:Hypothalamus / Q000378:metabolism; D009075:MSH Release-Inhibiting Hormone / Q000378:metabolism*; D051379:Mice; D010121:Oxytocin / Q000378:metabolism; D053719:Tandem Mass Spectrometry
D010121:Oxytocin; D009075:MSH Release-Inhibiting Hormone