Transplantation of fetal nigral cells reverses the increase of preproenkephalin mRNA levels in the rat striatum caused by 6-OHDA lesion of the dopaminergic nigrostriatal pathway: a quantitative in situ hybridization study

Brain Res Mol Brain Res. 1993 May;18(3):221-7. doi: 10.1016/0169-328x(93)90193-s.


Unilateral 6-hydroxydopamine (6-OHDA)-induced lesion of the nigrostriatal dopamine (DA) pathway causes a significant increase of preproenkephalin (PPE) messenger RNA (mRNA) levels in the DA-depleted striatum in rat brain. Using an in situ hybridization (ISH) technique and computer-assisted microdensitometry, we quantified the changes in PPE mRNA levels in the striatum. Seven months after lesion, levels of PPE mRNA were 75% higher in the DA-depleted striatum than in the contralateral control striatum of the same animal or in the striatum of sham control animals. The implantation of embryonic dopaminergic neurons into the denervated striatum led to a complete reversal of this increase and, in grafted animals, levels of PPE mRNA were at control values. Moreover, this reversal extended beyond the areas reinnervated by the grafted dopaminergic neurons.

MeSH terms

  • Animals
  • Autoradiography
  • Binding Sites
  • Brain Tissue Transplantation / physiology*
  • Corpus Striatum / drug effects
  • Corpus Striatum / physiology*
  • Enkephalins / biosynthesis*
  • Enkephalins / genetics
  • Fetal Tissue Transplantation / physiology
  • In Situ Hybridization
  • Male
  • Oxidopamine
  • Phosphorus Radioisotopes
  • Piperazines / metabolism
  • Protein Precursors / biosynthesis*
  • Protein Precursors / genetics
  • RNA, Messenger / analysis
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism*
  • Rats
  • Rats, Wistar
  • Reference Values
  • Substantia Nigra / physiology*
  • Substantia Nigra / transplantation*
  • Time Factors
  • Tritium


  • Enkephalins
  • Phosphorus Radioisotopes
  • Piperazines
  • Protein Precursors
  • RNA, Messenger
  • Tritium
  • Oxidopamine
  • preproenkephalin
  • 1-(2 (diphenylmethoxy)ethyl)-4-(3-phenylpropyl)piperazine