ADRENAL-MEDULLA AND PARKINSONS-DISEASE

Parkinson's disease has been described as a multisystem disorder that includes alterations in the function of the autonomic nervous system. The activity of the adrenal medulla in this disease has not been thoro ughly investigated. Previous reports are reviewed that demonstrate tha t the adrenal medullae of parkinsonian patients are compromised, havin g a decreased content of all catecholamines and several neuropeptides. An animal model was used to investigate whether the observations made in human patients were related to extended treatment with antiparkins onian medications or were a natural concomitant of the disease. Admini stration of L-dopa and/or carbidopa to C57BL mice for 4-16 weeks had n o significant effect on the level of any of the adrenal medullary cate cholamines. Treatment with MPTP 4-16 weeks prior to sacrifice did not deplete adrenal medullary catecholamines in these animals, thus not fu lly mimicking Parkinson's disease in this animal model. The only signi ficant effect was an interaction between group (MPTP or control) and t reatment with antiparkinsonian medications; L-dopa, in the absence and presence of carbidopa, had opposite effects in the two groups. Based primarily on the lack of effect of antiparkinsonian medications on adr enal medullary catecholamines, it was concluded that the adrenal medul lary depletion observed in human patients was a peripheral concomitant of Parkinson's disease. (C) 1994 Wiley-Liss, Inc.