RAT MESENCEPHALIC NEURONAL CELLS CULTURED FOR DIFFERENT PERIODS AS A MODEL OF DOPAMINE TRANSPORTER ONTOGENY

Ventral mesencephalic neurons contained only low-affinity and sodium-i ndependent binding sites of [H-3]WIN 35,428 (marker of dopamine transp orter) during the first 10 d in primary cultures. These sites were pre sent in cytosol, and they are not very probably related to dopamine tr ansporter. After 12 d in culture, membrane-bound, high-affinity, and s odium-dependent [H-3]WIN 35,428 binding sites were detected. In membra nes prepared from cells 14 d in culture, cocaine displaced [H-3]WIN 35 ,428 binding with similar potency to that in striatal membranes of adu lt rat brain. The high-affinity [H-3]WIN 35,428 binding sites in mesen cephalic neuronal cell cultures are very probably related to dopamine transporter. The development of high-affinity [H-3]WIN 35,428 binding sites in neurons cultured for different time periods could be a useful model of dopamine transporter ontogenesis.