A quantitative [14C]-2-deoxy-D-glucose study of brain stem nuclei during horizontal nystagmus induced by lesioning the lateral crista ampullaris of the rat.

Abstract

A study of the brainstem of the rat during horizontal nystagmus using the quantitative 2-deoxy-D-glucose technique reflected changes in the functional activity of cell groups based on their glucose utilization rates. Horizontal nystagmus was induced by unilateral crista ampullectomy of the horizontal canal. Comparisons of glucose utilization rates were made between experimental and control groups as well as from side to side within each group. There was a decrease of the ipsilateral medial and superior vestibular nuclei with a concomitant increase in the contralateral medial vestibular nucleus when compared to control. The medial rectus motor division of the ipsilateral oculomotor nucleus showed an increase whereas the ipsilateral abducens and the ipsilateral nucleus prepositus hypoglossi exhibited a decline in their utilization rates. The extra ocular motor nuclei responsible for the excitatory fast phase of nystagmus utilizes more substrate than those involved in the slow phase. An increase was also measured in the ipsilateral lobule of the cerebellar nodulus. The lateral reticular nucleus showed a bilateral decrease in its glucose utilization rate when compared to control.