Effect of simulated microgravity on PGE2-induced edema and hyperalgesia in rat paws: pharmacological data and biochemical correlates

J Gravit Physiol. 2004 Jul;11(2):P41-2.

Abstract

The aim of the present study has been to investigate the effect of conditions of modeled microgravity using a three-dimensional clinostat (Random Positioning Machine, RPM) on edema and thermal hyperalgesia induced by prostaglandin E2 (PGE2) in the hind paw of rat. Our results showed that RPM reduced PGE2-evoked edema associated to a significant decrease in hyperalgesia compared to ground control animals. To further characterize the mechanisms by which RPM induces anti-inflammatory and anti-hyperalgesic action, we performed biochemical assays of PGE2 and Western immunoblot experiments to assess whether the intraplantar administration of exogenous PGE2 modifies the expression of the iNOS. These results showed that RPM diminished the levels of PGE2 in exudates of paws previously treated with PGE2, but did not influence the iNOS expression.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Carrageenan
  • Dinoprostone / pharmacology*
  • Edema / prevention & control*
  • Foot
  • Hot Temperature
  • Hyperalgesia / prevention & control*
  • Male
  • Nitric Oxide Synthase / drug effects
  • Nitric Oxide Synthase / metabolism
  • Nociceptors / drug effects
  • Pain / prevention & control
  • Rats
  • Rats, Wistar
  • Rotation
  • Weightlessness Simulation*

Substances

  • Carrageenan
  • Nitric Oxide Synthase
  • Dinoprostone