Intrastriatal grafts of adrenal medulla in hemiparkinsonian rats--ultrastructural study.

The aim of the study was to investigate the ultrastructure of the right striatum after intrastriatal adrenal medulla grafts in Wistar rats with a 6-OHDA unilateral lesion of the compact part of the right substantia nigra (SN). 12 adult rats were investigated. Two rats were intact, 2 received a sham SN-lesion. Ungerstedt's rotational test confirmed a significant lateral SN-lesion in all the animals. Two weeks after the SN lesion small samples of the adrenal medulla of 2-month old Wistar rats were prepared (0.5 mm3) and implanted stereotaxically into the middle-paraventricular region of the right striatum. The animals were perfused with 2.5% glutaraldehyd according to the following patern: 2--after 1 week of survival, 2--after 3 weeks, 2--after 6 weeks, and 2--after 3 months. 10 samples of ca 1 mm3 were taken from 3 regions of the right striatum (1) the region of the graft, (2) the region in the neighbourhood of the graft, (3) tissue at a long distance from the transplant. Macroscopic observation showed granulomatous-like tissue at the place of the implantation of the graft after 1 week of survival. After 3 weeks and later only the evacuated cavity was observed instead of the graft. A routine electron microscopic procedure was used to expose the material in a JEM 100 B electron microscope. The study of the ultrastructure indicated many leucocytes and microglia cells in the region of the graft as well as features of destruction of the adrenal medulla cells in the rats perfused 1 and 3 weeks after transplantation.(ABSTRACT TRUNCATED AT 250 WORDS)