In situ hybridization histochemistry and immunocytochemistry reveal an increase in spinal dynorphin biosynthesis in a rat model of peripheral inflammation and hyperalgesia

摘要: Abstract Dynorphin, an opioid peptide, is thought to play important role in the modulation of nociceptive neural circuits at level spinal cord. In a model peripheral inflammation and hyperalgesia, oligodeoxyribonucleotide probe complementary portion preprodynorphin mRNA antisera dynorphin A-(1-8) were used localize changes peptide individual cord neurons. Intraplantar injection rats complete Freund's adjuvant resulted edema hyperalgesia radiant heat stimulation injected hind paw that reached peak 4 days. At same time, situ hybridization histochemistry immunocytochemistry identified increase transcription was paralleled by peptide. These seen neurons medial two-thirds laminae I II V VI lumbar segments receiving innervation from inflamed paw. Since demonstrating biosynthesis are located both superficial deep dorsal horn laminae, our data provide evidence for these two distinct locations.