Adrenal medulla grafts into the rat striatum--an evaluation of survival and dynamics of the host brain response.

Abstract

Allogenic adrenal medullary tissue was implanted into the striatum of 68 rats. The material was evaluated by routine histological, histochemical, immunocytochemical as well as histofluorescence techniques 1, 3, 7, 14, 21 and 42 days after implantation. The viability of chromaffin cells continued through the 21st day after the implantation. The host brain tissue responded in two ways. First, by macrophagic resorption of the progressively necrotic graft in the experimental group and of the damaged area along the needle tract, noted both in experimental and control animals. This was accompanied by demarcation by proliferating reactive astrocytes and microglial cells. Second, by lymphocyte infiltration in the graft and around it, detected only in the experimental group which suggested immunological rejection.