Sensitization of nociceptive C-fibers in zinc-deficient rats

Am J Physiol. 1995 Jun;268(6 Pt 2):R1423-8. doi: 10.1152/ajpregu.1995.268.6.R1423.


A marked decrease in zinc concentration was observed in plasma (P < 0.001), hindpaw skin (P < 0.01), and dorsal skin (P < 0.01) in zinc-deficient rats (rats fed a zinc-deficient diet for 3 wk), compared with the control rats fed the same zinc-deficient diet supplemented with ZnCO3 (50 mg/kg diet). The threshold intensity needed to elicit vasodilatation in the hindpaw skin of the zinc-deficient rats on electrical stimulation of the saphenous nerve in a peripheral direction was markedly lower (P < 0.01) than that in the control rats. No difference was observed between control (n = 5) and zinc-deficient rats (n = 5) in the magnitude of the plasma extravasation evoked by either histamine or substance P. There was no difference between control and zinc-deficient rats in terms of the dose-response curve for release of histamine by substance P. Prostaglandin E2 (PGE2) concentration in the hindpaw skin of the zinc-deficient rats was nearly fourfold higher (P < 0.01) than that of the control rats, whereas no difference in the leukotriene B4 level in the hindpaw skin was observed between control and zinc-deficient rats. From the present study, it seems likely that an increased level of PGE2 in the vicinity of the nociceptive C-fiber terminals in the hindpaw skin of zinc-deficient rats may sensitize the terminals of the nociceptive C-fibers of the saphenous afferent nerve in the hindpaw and thus facilitate the production of antidromic vasodilatation.

MeSH terms

  • Afferent Pathways / physiology
  • Animals
  • Carbonates / pharmacology*
  • Dinoprostone / metabolism
  • Electric Stimulation
  • Hindlimb
  • Histamine / pharmacology
  • Leukotriene B4 / metabolism
  • Male
  • Nerve Fibers / drug effects
  • Nerve Fibers / physiology*
  • Nociceptors / drug effects
  • Nociceptors / physiology*
  • Peripheral Nerves / drug effects
  • Peripheral Nerves / physiology*
  • Rats
  • Rats, Wistar
  • Reference Values
  • Regional Blood Flow
  • Skin / blood supply
  • Skin / innervation
  • Skin / metabolism
  • Substance P / pharmacology
  • Vasodilation / drug effects
  • Zinc / deficiency*
  • Zinc / metabolism
  • Zinc Compounds / pharmacology*


  • Carbonates
  • Zinc Compounds
  • Leukotriene B4
  • Substance P
  • Histamine
  • zinc carbonate
  • Zinc
  • Dinoprostone