%0 Journal Article
%T Effect of Peptidase Inhibitors on Dynorphin A (1-17) or (1-13)-Induced Antinociception and Toxicity at Spinal Level
%A Mitsumasa Matsuda
%A Masanobu Yoshikawa
%A Takugi Kan
%A Mariko Watanabe
%A Junko Ajimi
%A Shigeru Takahashi
%A Masaaki Miura
%A Kenji Ito
%A Hiroyuki Kobayashi
%A Toshiyasu Suzuki
%J Pharmacology & Pharmacy
%P 33-51
%@ 2157-9431
%D 2017
%I Scientific Research Publishing
%R 10.4236/pp.2017.82003
%X Our group has earlier demonstrated that three enzymes sensitive to peptidase inhibitors (PIs), amastatin (A)-, captopril (C)-, and phosphoramidon (P), played an important role in inactivation of enkephalins at the spinal level. Dynorphin-converting enzyme (DCE) hydrolyzes dynorphin (Dyn) A (1-17) or Dyn A (1-13) mainly at the Arg6-Arg7 bond. Dynorphin A and its derived peptides interact with opioid and glutamate receptors at their N- and C-terminals, respectively. The purpose of the present study was to evaluate the antinociceptive potency and toxicity of intrathecal administered Dyn A (1-17), Dyn A (1-13), or Dyn A (1-6) under pretreatment with ACP and/or the DCE inhibitor p-hydroxymercuribenzoate (PHMB). The effect of these PIs on Dyn A (1-17)-induced inhibition of electrically-evoked contractions in mouse vas deferens was also investigated. The inhibitory potency of Dyn A (1-17) on electrically-evoked contractions in mouse vas deferens under pretreatment with ACP was higher than that with AC, AP, or CP. Pretreatment with ACP augmented Dyn A (1-17) or (1-13)-induced antinociception by approximately 50- or 30-fold with no sign of allodynia when administered intrathecally at low doses. Pretreatment with ACP and PHMB induced neuropathy. These findings showed that intrathecal administration of low-dose Dyn A (1-17) or DynA (1-13) increased antinociception under pretreatment with ACP, but without signs of allodynia in rat.
%K Dynorphin A
%K Peptidase
%K Dynorphin-Converting Enzyme
%K Antinociception
%K Allodynia
%U http://www.scirp.org/journal/PaperInformation.aspx?PaperID=74072