Use of surface enhanced laser desorption/ionization-time of flight mass spectrometry (SELDI-TOF MS) to study protein expression in a rat model of cocaine withdrawal

SELDI-TOF MS is an analytical technology that combines chromatography and mass spectrometry. It is being exploited for the measurement of numerous proteins in serum, less often in organ tissue (rarely in brain). We applied SELDI-TOF MS technology to study protein expression in the brain of rats withdrawn from repeated cocaine exposure. Our goals were to optimize sample preparation and ProteinChip„¥ Array protocols for brain tissue, to verify the reproducibility of SELDI-TOF mass spectra, and to determine whether SELDI-TOF MS detects differentially expressed proteins in cocaine- vs. saline-treated rats. Consequently, we have developed an optimal protocol and generated a reproducible spectra with six dominant peaks in all test samples. We have found two peaks (m/z: 5179, 5030) significantly increased (p <. 05) in cocaine-treated rats. In summary, the application of SELDI-TOF MS to the study of protein expression in a rat model of cocaine withdrawal is feasible and potentially informative.