R. Levy et al., STRIATAL EXPRESSION OF SUBSTANCE-P AND METHIONIN-ENKEPHALIN GENES IN PATIENTS WITH PARKINSONS-DISEASE, Neuroscience letters, 199(3), 1995, pp. 220-224
The striatal expression of substance P (SP) and methionin-enkephalin (
met-enk) genes was studied post mortem by in situ hybridization in pat
ients with Parkinson's disease and a group of control subjects. No sig
nificant difference in striatal expression of these two neuropeptide m
essenger RNAs (mRNAs) was found in the patients compared with control
subjects. This contrasts with animal models of parkinsonism, where exp
ression of SP mRNA is decreased and met-enk mRNA increased. Possible e
xplanations include: (1) compensatory mechanisms, which may develop du
ring the long term evolution of Parkinson's disease; (2) normalized ex
pression of the two genes resulting from chronic L-DOPA therapy.