Differential effect of Adrenoceptor on Functional Activation and Connectivity
نویسندگان
چکیده
Purpose Functional MRI (fMRI) has been used in detecting task-related hemodynamic responses following neuronal activation. Spontaneous low frequency fMRI signal fluctuations at resting state have emerged as another means to study brain function (1). The mechanism underlying these fluctuations in the brain has remained elusive and its neural origin still debatable. A major concern in studying the mechanism in rodents is the use of anesthesia. The alpha 2-adrenoreceptor agonist, medetomidine, has recently been used for functional activity and resting state studies because it allows longitudinal fMRI studies (2, 3). To understand the effect of medetomidine on resting state fluctuations, we studied the functional activation of the rat brain induced by forepaw stimulation and resting state functional connectivity under various dosages of medetomidine.
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