Decreased neuropeptide content in the spinal cord of aged rats: the effectof GM1 ganglioside

methionine-enkephalin (Met-Enk) and dynorphin A(1-13) (Dyn A) in the spinal cord of aged Sprague-Dawley rats and the effect of GM1 ganglioside on thes e neuropeptides. SP and Met-Enk, but not Dyn A, were decreased in both dors al and ventral horns of the aged spinal cord. Treatment with GM1 gangliosid e (30 mg/kg i.p., daily for 30 days) restored, in part, the neuropeptide de ficits in the ventral horns, but not in the dorsal horns. This information might be important for understanding the sensory and motor deficits associa ted with ageing, and how the spinal cord neuropeptides might be amplified i n the aged spinal cord. (C) 1999 Lippincott Williams & Wilkins.