International audience; The Blood Oxygen Level Dependent (BOLD) signal, used in resting-state functional Magnetic Resonance Imaging (fMRI), is tighly linked to Cerebral Blood Flow (CBF). This study evaluates the impact of the CBF on the low-frequencies BOLD fluctuations and on four physiological parameters during resting state in 5 groups of rats, Wistar (W) and Long-Evans (L) anesthetized with Isoflurane (Iso), Medetomidine (Med), Etomidate (Eto) and Urethane (Ure). It is shown that the CBF is not related to physiological parameters, and there exists a range of CBF values where the BOLD fluctations are sufficiently high for being used in any other analysis.