A noxious stimulus induces the preprotachykinin-A gene expression in the rat dorsal root ganglion: a quantitative study using in situ hybridization histochemistry

Brain Res. 1988 Aug;464(1):31-5. doi: 10.1016/0169-328x(88)90015-0.


Using in situ hybridization histochemistry, we examined the biosynthesis of the preprotachykinin-A (PPTA) mRNAs, which code for substance P (SP) and also a related peptide, substance K (SK), in the rat dorsal root ganglion (DRG). The animals were injected with a small amount of formalin in the right hindpaw for nociceptive chemical stimulation. Analysis of hybridization signals in the emulsion autoradiography showed that the lumbar-5 DRG neurons expressing PPTA mRNAs were significantly increased in number and signal intensity on the formalin-injected side. Such elevation of the PPTA mRNA expression in the DRG was observed as early as 3 h after formalin injection. These results show that the expression of the PPTA gene is activated by chemogenic noxious stimuli.

MeSH terms

  • Animals
  • DNA
  • Formaldehyde
  • Ganglia, Spinal / metabolism*
  • Ganglia, Spinal / physiology
  • Gene Expression Regulation*
  • Male
  • Nociceptors / drug effects
  • Nociceptors / physiology*
  • Nucleic Acid Hybridization
  • Pain / metabolism*
  • Protein Precursors / metabolism*
  • Protein Precursors / physiology
  • RNA, Messenger / metabolism*
  • Rats
  • Rats, Inbred Strains
  • Tachykinins / metabolism*
  • Tachykinins / physiology
  • Time Factors


  • Protein Precursors
  • RNA, Messenger
  • Tachykinins
  • preprotachykinin
  • Formaldehyde
  • DNA