Dose and time dependent effects of morphine on the incorporation of [3H]valine into soluble brain and liver proteins.

Morphine (10(-6)-10(-5) M) causes an increase in incorporation of [3H]valine into soluble proteins during 4 hr in rat brain cortical slices, liver slices and cultivated astroglial cells. The effects are dose-dependent. They are neither cell specific nor strictly related to classical opiate receptors. Pulse-labeling with [3H]valine for 60 min after incubation in 10(-6)-10(-5) M morphine, resolves time-dependent changes in incorporation, with both increases and decreases in protein metabolism.