Locus coeruleus input affects glucose metabolism in activated rat barrel cortex.

Significant depletion (greater than 50%) of neocortical norepinephrine (NE), 2 weeks after unilateral 6-hydroxydopamine lesions of the locus coeruleus, led to a small (8%), ipsilateral decrease in total C3 vibrissa column 14C-2-deoxyglucose uptake, but a larger (24-32%) increase in the areal extent of this uptake into the metabolic representation of both the C3 column and barrel of the rat somatosensory (SmI) cortex during stimulation of the contralateral C3 facial vibrissae. This suggests a predominantly inhibitory role for NE in modulating SmI oxidative metabolism during physiologic stimulation.