ON CHLORPROMAZINE BINDING IN VIVO

[摘要] Intraperitoneally administered CPZ [chlorpromazine] was shown in vivo to localize in tissues containing melanin. This localization would not occur unless some form of binding between the CPZ and some constituent unique to these pigmented tissues (assumed to be the pigment itself) existed. The observed turn-over of the CPZ requires that the major portion of this drug is bound reversibly, although a small fraction may be permanently incorporated into the pigment. The rates of disappearance of the radioactivity from the non-pigmented tissues was markedly higher particularly so for the brain. White light is adequate for the production of free radicals from CPZ, and this suggests a mechanism of action for the clinical hyperpigmenta-tion and ocular abnormalities observed in patients receiving large amounts of phenothiazine drugs.