For sarcosyl extraction 50 µl of brain homogenates were mixed with 85 µl of homogenization buffer (135 µl final volume). 15 µl of 100% sucrose were added to each sample to then centrifuge at 20,000 g for 20 min at 4 °C. The supernatant was collected and sarcosyl 20% was added to each sample to reach 1% final concentration. Samples were incubated under agitation for 1 h at RT and centrifuged at 100,000 g for 1 h at 4 °C. The collected supernatant corresponded to the sarcosyl soluble fraction. The pellet obtained, called sarcosyl insoluble fraction, was resuspended in 35 µl of 50 mM Tris-Cl pH 7.4.