HOMEPRODUCTSCOMPANYCONTACTFAQResearchDictionaryPharmaSign Up FREE or Login

Lipopolysaccharide evokes the modulation of brain cytochrome P4501A in the rat.

Abstract
The cytochrome P450 enzyme system is a multigene family of enzymes that is modulated in the liver during systemic inflammatory responses or during infection Several forms of the enzyme are expressed in discrete areas of the brain and likely play a critical role in the metabolism of drugs and endogenous chemicals in the central nervous system (CNS). Even though the brain responds to inflammation in a manner different from most tissues, we examined the possible modification of a major cytochrome P450 form (CYP1A) in the brain during inflammation confined to that organ. Total brain CYP1A activity, as measured by ethoxyresorufin dealkylase (EROD), was downregulated 24 and 48 h following the administration of a single dose of lipopolysaccharide (LPS). Regionally, a similar effect was determined in the cortex, hippocampus and the mid-brain but the activity in the cerebellum was unaffected. The examination of coronal brain sections using an antibody directed against CYP1A indicated that the enzyme was distributed in discrete cells of the hippocampus, thalamus and cortex and in the tanycytes surrounding the third ventricle. In each of these areas, the immunoreactivity was diminished in animals receiving LPS as compared to saline-treated animals. LPS also evoked the expression of the small molecular weight heat shock protein hsp27 throughout the brain indicating the development of an inflammatory response. These studies indicate that inflammation localized to the CNS causes an alteration in the levels and activity of a major cytochrome P450 form in the brain. This could have implications to the metabolism or activation of drugs and endogenous chemicals in the CNS during a disease state that features an inflammatory component.
AuthorsK W Renton, S Dibb, T L Levatte
JournalBrain research (Brain Res) Vol. 842 Issue 1 Pg. 139-47 (Sep 18 1999) ISSN: 0006-8993 [Print] Netherlands
PMID10526104 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
Chemical References
  • Endotoxins
  • Lipopolysaccharides
  • endotoxin, Escherichia coli
  • Cytochrome P-450 CYP1A1
  • Cytochrome P-450 CYP1A2
Topics
  • Animals
  • Brain (drug effects, enzymology)
  • Cytochrome P-450 CYP1A1 (metabolism)
  • Cytochrome P-450 CYP1A2 (metabolism)
  • Endotoxins (pharmacology)
  • Escherichia coli
  • Immunohistochemistry
  • Injections, Intraventricular
  • Lateral Ventricles (physiology)
  • Lipopolysaccharides (pharmacology)
  • Male
  • Rats
  • Rats, Sprague-Dawley
  • Time Factors

Join CureHunter, for free Research Interface BASIC access!

Take advantage of free CureHunter research engine access to explore the best drug and treatment options for any disease. Find out why thousands of doctors, pharma researchers and patient activists around the world use CureHunter every day.
Realize the full power of the drug-disease research graph!


Choose Username:
Email:
Password:
Verify Password:
Enter Code Shown: