In situ hybridization histochemistry and immunocytochemistry reveal an increase in spinal dynorphin biosynthesis in a rat model of peripheral inflammation and hyperalgesia.
AUTOR(ES)
Ruda, M A
RESUMO
Dynorphin, an opioid peptide, is thought to play an important role in the modulation of nociceptive neural circuits at the level of the spinal cord. In a model of peripheral inflammation and hyperalgesia, an oligodeoxyribonucleotide probe complementary to a portion of preprodynorphin mRNA and antisera to dynorphin A-(1-8) were used to localize changes in dynorphin mRNA and peptide to individual spinal cord neurons. Intraplantar injection in rats of complete Freund's adjuvant resulted in edema and hyperalgesia to radiant heat stimulation of the injected hind paw that reached a peak at 4 days. At the same time, in situ hybridization histochemistry and immunocytochemistry identified an increase in transcription of preprodynorphin mRNA that was paralleled by an increase in dynorphin peptide. These changes were seen in spinal neurons in the medial two-thirds of laminae I and II and in laminae V and VI of lumbar segments receiving innervation from the inflamed paw. Since neurons demonstrating the increase in dynorphin biosynthesis are located in both the superficial and deep dorsal horn laminae, our data provide evidence for opioid modulation of nociceptive neural circuits in these two distinct spinal locations.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=279603Documentos Relacionados
- Induction of inhibitory factor κBα mRNA in the central nervous system after peripheral lipopolysaccharide administration: An in situ hybridization histochemistry study in the rat
- Marked increase in nitric oxide synthase mRNA in rat dorsal root ganglia after peripheral axotomy: in situ hybridization and functional studies.
- Analysis by immunocytochemistry and in situ hybridization of renin and its mRNA in kidney, testis, adrenal, and pituitary of the rat.
- Organization of small nucleolar ribonucleoproteins (snoRNPs) by fluorescence in situ hybridization and immunocytochemistry.
- Localization of the mRNA for the dopamine D2 receptor in the rat brain by in situ hybridization histochemistry.