Reduction in the ratio of beta-preprotachykinin to preproenkephalin messenger RNA expression in postmortem human putamen during aging and in patients with status lacunaris. Implications for the susceptibility to parkinsonism.
Gamma-aminobutyric acid (GABA)/substance P (SP) neurons and GABA/enkephalin (Enk) neurons in the striatum exert opposing influence on the regulation of movement. The loss of GABA/SP neurons results in hypokinetic disorders (parkinsonism), whereas the loss of GABA/Enk neurons results in hyperkinetic disorders (e.g. chorea). The present study determined age-related changes in the beta-preprotachykinin (the precursor of SP) and preproenkaphalin (the precursor of Enk) messenger RNA (mRNA) ratio in the postmortem human putamen using the reverse transcription-polymerase chain reaction (RT-PCR). The ratio of beta-preprotachykinin to preproenkephalin mRNA expression decreased with age. The reduction in the beta-preprotachykinin/preproenkephalin mRNA ratio was more marked in cases with multiple small infarcts (status lacunaris) in the putamen. These findings may in part explain the susceptibility of the elderly, particularly of those with ischemic changes in the striatum to hypokinetic disorders.
Tohgi
H
H
Department of Neurology, Iwate Medical University, Morioka, Japan.
Utsugisawa
K
K
Yoshimura
M
M
Yamagata
M
M
Nagane
Y
Y
Saitoh
K
K
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000378:metabolism*; D002544:Cerebral Infarction / Q000378:metabolism*; D004198:Disease Susceptibility; D004745:Enkephalins / Q000235:genetics*; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000378:metabolism; D016133:Polymerase Chain Reaction / Q000379:methods; D011498:Protein Precursors / Q000235:genetics*; D011699:Putamen / Q000378:metabolism*; D012333:RNA, Messenger / Q000096:biosynthesis*; D015320:Tachykinins / Q000235:genetics*; D014158:Transcription, Genetic
D004745:Enkephalins; D011498:Protein Precursors; D012333:RNA, Messenger; D015320:Tachykinins; C044206:preprotachykinin; C033660:preproenkephalin