Beta-adrenoreceptor antagonists attenuate brain injury after transient focal ischemia in rats

Anesth Analg. 2006 Sep;103(3):658-63. doi: 10.1213/01.ane.0000228859.95126.69.

Abstract

Beta-adrenoreceptor antagonists experimentally reduce cardiac and renal injury after ischemia and are also clinically useful for myocardial infarction and severe burns. In addition, beta-adrenoreceptor antagonists provide neuroprotective effects after focal cerebral ischemia in experimental settings. We conducted the present study to compare the neuroprotective effects of several beta-adrenoreceptor antagonists in rat transient focal cerebral ischemia. Halothane-anesthetized normothermic adult male Sprague-Dawley rats were subjected to 2 h of middle cerebral artery occlusion using the intraluminal suture technique confirmed by laser Doppler flowmetry. Rats received an IV infusion of saline 0.5 mL/h, propranolol 100 microg x kg(-1) x min(-1), carvedilol 4 microg x kg(-1) x min(-1), esmolol 200 microg x kg(-1) x min(-1), or landiolol 50 microg x kg(-1) x min(-1) (n = 6 in each group). Infusion was initiated 30 min before middle cerebral artery occlusion and continued for 24 h. Additional rats received esmolol 50 microg x kg(-1) x min(-1) or landiolol 10 microg x kg(-1) x min(-1) intrathecally (IT) via the cisterna magna (n = 5 in each group), according to the same experimental protocol. The neurological deficit score was evaluated at 22 h after reperfusion, and the brains were removed and stained with triphenyltetrazolium chloride for evaluation of infarct volume. Additional rats that received saline, esmolol, and landiolol IV (n = 6 in each group) were allowed to survive for 7 days followed by measurement of infarct size. Neurological deficit scores were smaller in rats treated with propranolol-IV, carvedilol-IV, esmolol-IV, landiolol-IV, esmolol-IT, and landiolol-IT compared with saline-treated rats (P < 0.05). Cortical and striatum infarct volumes were less in the rats receiving beta-adrenoreceptor antagonists via either IV or IT than in saline-treated rats (P < 0.05). We conclude that beta-adrenoreceptor antagonists improve neurological and histological outcomes after transient focal cerebral ischemia in rats independent of administration route.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adrenergic beta-Antagonists / pharmacology*
  • Anesthesia
  • Anesthetics, Inhalation / pharmacology
  • Animals
  • Brain / drug effects
  • Carbazoles / pharmacology
  • Carvedilol
  • Halothane / pharmacology
  • Ischemic Attack, Transient / drug therapy*
  • Male
  • Morpholines / pharmacology
  • Myocardial Infarction / drug therapy
  • Propanolamines / pharmacology
  • Propranolol / pharmacology
  • Rats
  • Rats, Sprague-Dawley
  • Tetrazolium Salts / pharmacology
  • Urea / analogs & derivatives
  • Urea / pharmacology

Substances

  • Adrenergic beta-Antagonists
  • Anesthetics, Inhalation
  • Carbazoles
  • Morpholines
  • Propanolamines
  • Tetrazolium Salts
  • Carvedilol
  • landiolol
  • triphenyltetrazolium
  • Urea
  • Propranolol
  • esmolol
  • Halothane