Local Cerebral Glucose Utilization in Rats with Decerebrate Rigidity and Effects of Centrally Acting Muscle Relaxants, Diazepam and Tizanidine

Abstract

Local cerebral glucose utilization (LCGU) was investigated in rats with decerebrate rigidity using the [¹⁴C]2-deoxyglucose (2DG) method in order to identify the site responsible for the rigidity. LCGU was increased in the medial vestibular nucleus, the fastigial nucleus, the interpositus nucleus and the dentate nucleus during decerebrate rigidity. Diazepam and tizanidine, centrally acting muscle relaxants, reduced the increase of LCGU in the vestibular and cerebellar nuclei. These results suggest that the vestibular and cerebellar nuclei are the possible sites responsible for the development of decerebrate rigidity and the action of some centrally acting muscle relaxants.