Role of electrical activity in axotomy-induced increased glucose use

Glucose use as demonstrated by 2-deoxyglucose autoradiography increases in the hypoglossal nucleus after axotomy of the hypoglossal nerve. There are several possible explanations for this increase, including increased energy metabolism to support increased protein, RNA, and lipid synthesis during regeneration or, alternatively, increased electrical activity associated with the site of nerve transection or alterations in the neurolemma. To evaluate the possible role of electrical activity, we recorded spike activity in the hypoglossal nucleus after axotomy and evaluated glucose uptake in the hypoglossal nucleus after xylocaine application to the proximal nerve stump. There was no evidence from these experiments that an increased number of action potentials is responsible for the increased glucose use after axotomy.