Changes in brain functional magnetic resonance imaging during noxious electric stimulation of forepaw and / 中华麻醉学杂志

ABSTRACT

ObjectiveTo investigate the change in brain functional magnetic resonance imaging (fMRI)during noxious electric stimu lation of forepaw and tail in rats.MethodsForty-eight healthy SD rats of both sexes weighing 300-450 g which responded sensitively to electrical stimulation as shown by Y-maze were randomly divided into 2 groups ( n =24 each) receiving nociceptive electric stimulation of left forepaw (group LF) and tail (group T) respectively.The animals were anesthetized with intraperitoneal 10％ chloral hydrate 250-300 mg/kg.Brain fMRI was performed at 30 min after disappearance of righting reflex in both groups when electric stimulations were delivered intermittently to forepaw or tail.The images were analyzed with SPM2 software.ResultsPrimary and secondary somatosensory cortex,posterior cingutate cortex,amygdaloid nucleus and ventral posterolateral thalamic nucleus were activated in group T.Right accumbens nucleus,right primary somatosensory cortex,right ventral posterolateral thalamic nucleus and right posterior cingutate cortex were activated in group LF.ConclusionDifferent brain areas are activated by noxious electric stimulation of different parts of body as shown by brain fMRI.