Deprenyl reduces the death of motoneurons caused by axotomy.
Deprenyl, a monoamine oxidase B inhibitor, appears to slow the progression of neurological deficits in Parkinson's disease and cognitive decline in Alzheimer's disease. The mechanisms for the slowing of the diseases are unknown. Deprenyl can reduce the death of murine substantia nigra neurons when administered after the neurons are damaged in MPTP parkinsonism by increasing the neurons' survival after they are damaged, rather than by just protecting the neurons against damage by blocking the conversion of MPTP to its active form as was previously thought. The death of immature motoneurons after separation from their muscle targets by axotomy provides a model for assessing trophically dependent neuronal survival. To determine whether deprenyl can alter the survival of neurons other than those in the substantia nigra, we examined the survival of rat facial motoneurons after axotomy at 14 days of age. Using a combination of immunocytochemistry for choline acetyl transferase and Nissl staining, we found that deprenyl treatment (10 mg/kg every second day) increased by 2.2 times the number of motoneurons surviving 21 days after the axotomy. This finding showed that deprenyl treatment can rescue neurons other than those in the substantia nigra and can compensate in part for the loss of target-derived trophic support caused by axotomy.
Salo
P T
PT
Centre for Research on Neurodegenerative Disorders, Faculty of Medicine, University of Toronto, Ontario, Canada.
Tatton
W G
WG
D000818:Animals; D001369:Axons / Q000187:drug effects / Q000502:physiology*; D016923:Cell Death / Q000187:drug effects*; D002467:Cell Nucleus / Q000187:drug effects; D002795:Choline O-Acetyltransferase / Q000378:metabolism; D005154:Facial Nerve / Q000166:cytology / Q000187:drug effects; D007150:Immunohistochemistry; D009046:Motor Neurons / Q000187:drug effects*; D051381:Rats; D011919:Rats, Inbred Strains; D012642:Selegiline / Q000494:pharmacology*; D013194:Staining and Labeling; D013378:Substantia Nigra / Q000166:cytology
D012642:Selegiline; D002795:Choline O-Acetyltransferase