Cav3.2-dependent hyperalgesia/allodynia following intrathecal and intraplantar zinc chelator administration in rodents

J Pharmacol Sci. 2023 Jun;152(2):86-89. doi: 10.1016/j.jphs.2023.03.007. Epub 2023 Apr 5.

Abstract

Cav3.2, a T-type calcium channel (T-channel) family member, is expressed in the nociceptors and spinal cord, and its activity is largely suppressed by zinc under physiological conditions. In rats, intrathecal and intraplantar administration of a zinc chelator, TPEN, caused T-channel-dependent mechanical hyperalgesia, and the intraplantar, but not intrathecal, TPEN induced Cav3.2 upregulation in the dorsal root ganglion. In mice, intraplantar TPEN also caused mechanical allodynia, which was abolished by T-channel inhibitors or Cav3.2 gene deletion. Together, spinal and peripheral zinc deficiency appears to enhance Cav3.2 activity in the spinal postsynaptic neurons and nociceptors, respectively, thereby promoting pain.

Keywords: Ca(v)3.2 T-type calcium channel; Hyperalgesia; Pain; TPEN; Zinc deficiency.

MeSH terms

  • Animals
  • Calcium Channels, T-Type* / genetics
  • Chelating Agents
  • Ganglia, Spinal
  • Hyperalgesia* / chemically induced
  • Mice
  • Rats
  • Rodentia
  • Zinc

Substances

  • Chelating Agents
  • Zinc
  • N,N,N',N'-tetrakis(2-pyridylmethyl)ethylenediamine
  • Calcium Channels, T-Type