Blockade of bradykinin B2 receptor more effectively reduces postischemic blood-brain barrier disruption and cytokines release than B1 receptor inhibition

Biochem Biophys Res Commun. 2009 Oct 16;388(2):205-11. doi: 10.1016/j.bbrc.2009.07.135. Epub 2009 Aug 5.

Abstract

Blood-brain barrier disruption and brain edema are detrimental in ischemic stroke. The kallikrein-kinin system appears to play an important role in the regulation of vascular permeability and is invoked in edema formation. The effects of kinins are mediated by bradykinin receptors B1R and B2R. However, little is known about the exact roles of bradykinin receptors in the early stage of cerebral ischemia. In this study, we demonstrated that ischemia upregulated the level of B1R and B2R at 24h after reperfusion by immunofluorescence assays, mainly expressed in astrocytes and neurons, respectively, in the ischemic penumbra. Moreover, B2R inhibition more effectively reduced neurological severity scores, blood-brain barrier permeability and cytokines release than B1R inhibition did. Additionally, B2R inhibition also significantly suppressed B1R protein level. Therefore, blockade of B2R may be a more effective strategy for the treatment of ischemic brain injury than B1R inhibition within 24h after reperfusion.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Astrocytes / metabolism
  • Astrocytes / pathology
  • Blood-Brain Barrier / drug effects
  • Blood-Brain Barrier / metabolism*
  • Bradykinin B1 Receptor Antagonists*
  • Bradykinin B2 Receptor Antagonists*
  • Brain Ischemia / drug therapy*
  • Brain Ischemia / metabolism
  • Brain Ischemia / pathology
  • Cytokines / metabolism*
  • Male
  • Neurons / metabolism
  • Neurons / pathology
  • Rats
  • Rats, Sprague-Dawley
  • Receptor, Bradykinin B1 / biosynthesis
  • Receptor, Bradykinin B2 / biosynthesis
  • Severity of Illness Index
  • Stroke / drug therapy*
  • Stroke / metabolism
  • Stroke / pathology

Substances

  • Bradykinin B1 Receptor Antagonists
  • Bradykinin B2 Receptor Antagonists
  • Cytokines
  • Receptor, Bradykinin B1
  • Receptor, Bradykinin B2