Fibrils are biomarkers for early stages of dementia. In this work, α-synuclein fibrils were injected in rat striatum. Brains were imaged ex-vivo using multi-frequency MR Elastography. Estimation of the real part kr of the complex wave number was made for each studied frequency in ROIs surrounding the inclusion, a contralateral control injection and the whole brain. Exponent of the frequency power law was derived from kr maps acquired at different frequencies. No difference was observed between kr values for the different ROIs, but the exponent was more important at the fibrils location, potentially indicating that multi-frequency MRE can detect fibrils.