Sustained Negative BOLD, CBF, CBV, and CMRO2 FMRI Responses to the Noxious Stimuli in the Rat Striatum at 1

Yen-Yu Ian Shih¹, Hsiao-Ying Wey¹, Qiang Shen¹, Timothy Q. Duong¹

We recently reported that noxious forepaw electrical stimulation increases spike activity but, surprisingly, decreases CBV fMRI signals in the striatum. The present study focused on investigating this apparent discrepancy by performing BOLD, CBF, CBV, and CMRO2 fMRI on the same animals associated with noxious electrical forepaw stimulation at 11.7T. Neurovascular coupling among these hemodynamic and metabolic parameters were analyzed. The animal model and multiparametric fMRI protocol herein may prove useful to study neurovascular uncoupling and dysfunction of the striatum in various neurological disorders.