Chronic (-) deprenyl administration increases dendritic arborization in CA3 neurons of hippocampus and AChE activity in specific regions of the primate brain.
The mechanism by which (-) deprenyl enhances cognitive function in Alzheimer's disease (AD) is not yet understood. (-) Deprenyl (0.2 mg/kg/day) was administered intramuscularly to adult male monkeys (n = 6) for 25 days. Control monkeys (n = 6) received physiological saline by the same route. The activity of acetylcholinesterase (AChE) in different brain regions and the dendritic arborization in CA3 pyramidal neurons of hippocampus were analysed. (-) Deprenyl-treated monkeys showed a significant increase in the AChE activity by 43% (p < 0.001) in the frontal cortex, by 39% (p < 0.025) in the motor cortex, by 66% (p < 0.001) in the hippocampus and by 26% (p < 0.05) in the striatum compared to controls. The branching points and the intersections of both apical and basal dendrites of CA3 hippocampal pyramidal neurons were also significantly increased in (-) deprenyl-treated monkeys. Enhanced AChE activity may increase dendritic arborization in the hippocampus and it may also play a role in improving cognitive functions observed in AD, following (-) deprenyl treatment.
Department of Neurophysiology, National Institute of Mental Health and Neurosciences, Bangalore, India.
M K
MK
Lakshmana
B S
BS
Rao
N K
NK
Dhingra
R
R
Ravikumar
Govindaiah
Ramachandra
B L
BL
Meti
T R
TR
Raju
D000110:Acetylcholinesterase / Q000378:metabolism*; D000818:Animals; D001921:Brain / Q000201:enzymology*; D003712:Dendrites / Q000187:drug effects* / Q000648:ultrastructure; D006624:Hippocampus / Q000166:cytology / Q000187:drug effects*; D008255:Macaca radiata; D008297:Male; D008996:Monoamine Oxidase Inhibitors / Q000494:pharmacology*; D017966:Pyramidal Cells / Q000187:drug effects* / Q000648:ultrastructure; D012642:Selegiline / Q000494:pharmacology*; D014018:Tissue Distribution
D008996:Monoamine Oxidase Inhibitors; D012642:Selegiline; D000110:Acetylcholinesterase