Subtle alterations in NMDA-stimulated cyclic GMP levels following lateral fluid percussion brain injury

M. D. Temple, T. M. Delahunty, R. J. Hamm, L. L. Phillips, Bruce G Lyeth, J. T. Povlishock

Research output: Contribution to journalArticle

3 Scopus citations

Abstract

This study examined whether NMDA-stimulated cyclic GMP levels were altered at two different time points following lateral fluid percussion injury. At 60 min and 15 days postinjury, the left and right hippocampi were dissected and chopped into mini-prisms. Each hippocampus was divided into five equal parts and incubated with either the phosphodiesterase inhibitor IBMX (3-isobutyl-1-methylxanthine, 500 μM) alone, IBMX and N-methyl-D-aspartic acid (NMDA) oR IBMX, NMDA, and glycine (10 MM). Two concentrations of NMDA were used: 500 or 1,000 μM. Tissues were then assayed for levels of cyclic GMP. Results indicated that there were no changes in basal levels of cyclic GMP at either postinjury time point. At 60 min postinjury, there were no significant main effects for injury or drug concentration. There was a significant injury x side interaction effect with increased levels of NMDA-stimulated cyclic GMP in the hippocampus ipsilateral to the injury impact and decreased cyclic GMP levels in the contralateral hippocampus. There were no significant alterations in NMDA-stimulated cyclic GMP levels at 15 days postinjury. The data from this study indicated that NMDA-stimulated cyclic GMP accumulation is differentially altered in the hippocampus ipsilateral and contralateral to the site of the injury at 1 h after injury, but is normalized by 15 days postinjury. These findings implicate NMDA-mediated intracellular signaling processes in the acute excitotoxic response to injury.

Original languageEnglish (US)
Pages (from-to)47-55
Number of pages9
JournalJournal of Neurotrauma
Volume18
Issue number1
StatePublished - 2001
Externally publishedYes

Keywords

  • Cyclic GMP
  • Hippocampus
  • N-methyl-D-aspartate receptor
  • Radioimmunoassay
  • Rats
  • Traumatic brain injury

ASJC Scopus subject areas

  • Clinical Neurology
  • Neuroscience(all)

Fingerprint Dive into the research topics of 'Subtle alterations in NMDA-stimulated cyclic GMP levels following lateral fluid percussion brain injury'. Together they form a unique fingerprint.

  • Cite this

    Temple, M. D., Delahunty, T. M., Hamm, R. J., Phillips, L. L., Lyeth, B. G., & Povlishock, J. T. (2001). Subtle alterations in NMDA-stimulated cyclic GMP levels following lateral fluid percussion brain injury. Journal of Neurotrauma, 18(1), 47-55.