Uptake of dihydromorphine- 3H by synaptosomes

Tritium-labeled dihydromorphine (DHM-3H) was accumulated by the synaptosomal fraction (nerve endings) of rat cerebral cortex. Particles derived from nerve endings by osmotic shock exhibited a higher concentration of DHM- 3H than did other subcellular fractions of brain when the isolated fractions were incubated with the drug . Nalorphine in large concentrations reduced the uptake of DHM- 3H by all fractions to the same degree. No difference was apparent in the uptake of DHM- 3H by subcellular fractions from non-tolerant and morphine-tolerant rats. The uptake of DHM- 3H by nerve endings was attributed to a binding phenomenon, although an active transport process may provide the drug an access to the binding sites in the intact tissue.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/33707/1/0000219.pd