Transplanted adrenal chromaffin cells in rat brain reduce lesion-induced rotational behaviour.

Abstract

Rats with unilateral lesions of substantia nigra pars compacta (SN), the area of the brain containing most dopamine-containing neurones, are a widely recognized animal model of Parkinson's disease1–4. When given dopamine agonists such as apomorphine, such rats rotate in a direction contralateral to the lesion, presumably because of the development of supersensitive dopamine receptors in the striatum ipsilateral to the lesion. When grafts of embryonic SN are placed in the lateral ventricle5,6, or into a transplant cavity7 adjacent to the striatum in animals with SN lesions, this rotational behaviour has been shown to decrease. Histochemical examinations have shown that axons from the grafts have grown into the striatum5–7, and biochemical measurements indicate that dopamine concentrations are increased in areas of the striatum adjacent to the SN grafts6. Nevertheless, an obvious problem with this technique, both for basic research and possible clinical applications, is the requirement for fetal central nervous donor tissue. We now describe how grafts of adrenal medulla can be used with similar effects, involving chromaffin cells.