In an experimental study human fetal adrenal medullary tissue was cultured and its cytoplasmatic catecholamine storing vesicles, NA and dopamine (DA) concentration controlled for 8 days. High secretory function of DA was maintained. This cultured human fetal tissue was transplanted to the subcortex of adult rabbits. Some of the crafts survived several months and maintained secretory function. In a clinical study 17 patients with Parkinson's disease received a transplantation of human fetal adrenal medullary tissue, which was cultured for one week and then transplanted into the head of both caudate nuclei. During follow-up of 3-18 months all of them improved.