A 53-year-old physician who had a 10-year history of progressive idiopathic parkinsonism survived for 4 months after an autologous adrenal-medulla-to-right-caudate autograft but he received little clinical benefit. A small number of chromaffin cells in the graft site survived; they expressed neurofilament proteins and chromogranin A, but scant tyrosine hydroxylase. The striatum on both sides showed almost complete loss of [3H]mazindol binding to dopamine-uptake sites; the density of dopamine receptors was decreased adjacent to the transplant but increased rostral to the transplant. These results demonstrate that autografted chromaffin cells can survive for 4 months after transplantation and that related changes in dopamine receptors can be quantified.