Adrenal medulla grafts produce blood-brain barrier dysfunction

The results of this study show that grafts of adrenal medulla into the rat brain parenchyma or ventricle produced significant blood-brain barrier dysfunction. Systemically administered protein rapidly entered either the grafts, the surrounding brain tissue or the cerebrospinal fluid. The grafted chromaffin cells avidly took up blood-borne radiolabelled amine. Thus, autonomic tissue transplants prevented normal reconstruction of the blood-brain barrier after surgery and indefinitely exposed host brain tissue to blood-borne compounds.