Interaction of NMDA and dopamine D2L receptors in human neuroblastoma SH-SY5Y cells.

To understand the mechanism of interaction of the dopamine D2L receptors with NMDA receptors, we have developed a model by transfecting human neuroblastoma SH-SY5Y cells with the human dopamine D2L receptor gene. In vitro blockade of NMDA receptors by the specific antagonists MK-801 and (+/-)-3-(2-carboxypiperazin-4-yl)-propyl-1-phosphonic acid (CPP) on human neuroblastoma SH-SY5Y cells expressing human dopamine D2L receptors resulted in a significant increase in the density of D2L receptors without a significant change in receptor affinity. Moreover, the dopamine receptor mRNA level increased by approximately 50% by the blockade of NMDA with MK-801. These results suggest a possible interaction of NMDA and dopamine D2L receptors in neuroblastoma SH-SY5Y cells. This system would serve as an excellent model to study the molecular mechanisms involved in the interaction of these two receptors.