Adrenal Medulla Transplants in Rodents and Nonhuman Primates: Regenerative Responses in the Host Brain

Abstract

The first clinical trials using intrastriatal adrenal autografts for the treatment of parkinsonism are now underway. From the early published reports it is clear that the procedures being used and the reported benefits from the grafts vary considerably from study to study. There are two general procedures being employed for the implantation of tissue. The first clinical experiments in Sweden (1,2) entailed the stereotactic placement of adrenal medullary tissue into the caudate or putamen using, in some instances, a steel spiral tissue carrier and, in other instances, the direct injection of tissue into the graft sites. In the first series involving two patients, the stereotactic implants were into the caudate nucleus (1). Backlund and his colleagues reported a moderate transient improvement during the first ten days postsurgery in the first patient and a more lasting improvement in the second patient which they suggested extended out to approximately six months. The criteria used were relatively subjective, making it difficult to quantitate the degree of recovery.