Age-related changes in [H-3]strychnine binding in the vestibular nuclei ofrats

Glycine plays an important role as a neurotransmitter in the four vestibula r nuclei (VN). The objective of this study was to determine if the levels o f glycine-receptor binding in the VN change as a function of age. Quantitat ive receptor autoradiography was performed on brainstem sections from three age groups (3, 18 and 26 months) of Fischer 344 rats to assess binding in the VN. Glycine receptors were localized using [H-3]strychnine binding;. St rychnine binding declined monotonically with increasing age, such that the level of strychnine binding in each of the VN in the 28-month-old animals w as approximately one-half that in the 3-month-olds. The age-related decreas e in levels of strychnine binding suggest altered glycinergic function in t he VN, which may in turn contribute to disturbances in equilibrium observed in the elderly. (C) 1999 Elsevier Science B.V. All rights reserved.