EFFECTS OF KAMIKIHITO, A TRADITIONAL CHINESE MEDICINE, ON NEUROTRANSMITTER RECEPTOR-BINDING IN THE AGED RAT-BRAIN DETERMINED BY IN-VITRO AUTORADIOGRAPHY - CHANGES IN DOPAMINE D-1 AND SEROTONIN 5-HT2A RECEPTOR-BINDING

Using in vitro autoradiography, we investigated the effects of Kamikih ito (KKT), a traditional Chinese medicine, on specific [H-3]SCH23390 b inding to dopamine D-1 receptors and [H-3]ketanserine binding to serot onin 5-HT2A receptors in the rat brain. Specific binding of both compo unds was affected by aging. Long-term administration of KKT resulted i n decreases in [H-3]SCH23390 binding to the cortex and hippocampus in aged rats, and in decreases in [H-3]ketanserine binding to the caudate /putamen in young rats. These results suggest that the changes in dopa mine D-1 and serotonin 5-HT2A receptor binding mag be involved in the central effects of KKT.