 They also show gene expression for dopamine receptors and transporters.Because of this, they are also studied by scientists who research effects of new drugs on dopamine receptors and transporters as well as the basic functions including dopamine secretion and uptake.Several scientists have concluded using lab rats with Parkinson's disease that these cells, when transplanted, reversed the effects of the disease by replacing those dopamine releasing neurons that had died and prevented other neurons from being destroyed by the disease.