The Coupling Between BOLD, CBF, CBV, and SEP Responses Under NO Blockade
Stefanovic B, Schwindt W, Silva A, Hoehn M
The inhibition of neuronally derived nitric oxide synthase was found to produce a pronounced and sustained disturbance in the coupling between hemodynamic and neuronal responses to functional stimulation in anesthetized rats. The administration of an ip bolus of 7-NI (50 mg/kg) attenuated the CBF response to forepaw stimulation by ~90%. In turn, BOLD response decreased by 60% and CBV by 50%, while the SEP amplitude declined by only ~25%. The disproportionately large hemodynamic, relative to neuronal response attenuation, testifies to an existence of a metabolic buffer in the tissue.