Influence of hypoxic-preconditioning on autonomic regulation following global ischemic brain injury in rats

Neurosci Lett. 2010 Aug 23;480(3):191-5. doi: 10.1016/j.neulet.2010.06.029. Epub 2010 Jun 16.

Abstract

Experimental and clinical studies have shown that autonomic imbalance is associated with morbidity and mortality due to global ischemic brain injury following cardiac arrest (CA). Although hypoxic-preconditioning (HP) has shown promising neuro-protection in the subsequent ischemic brain injury, the underlying mechanisms and its influence on autonomic regulation have not yet well-understood. In this study, we utilized baroreflex sensitivity (BRS) to investigate the protective effect of HP on autonomic regulation. We investigated changes in heart rate, arterial blood pressure (BP), and BRS within 4h after CA in rats. The relationship between BRS and neurodeficit score (NDS) was analyzed. Although no significant differences were found in heart rate and BP before and after CA between the control and the preconditioned groups, both BRS and NDS of preconditioned rats were clearly higher than that of the control rats during recovery after CA. Furthermore, BRS in the first 4h after CA highly correlated with NDS 24h after CA. These results imply that treatment with HP improves autonomic regulation and protects the brain from ischemic injury. The correlation between BRS and NDS also suggests that BRS can be a prognostic criterion for the level of brain injury after CA.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Autonomic Nervous System / physiology
  • Autonomic Nervous System Diseases / etiology
  • Autonomic Nervous System Diseases / physiopathology*
  • Baroreflex / physiology*
  • Blood Pressure / physiology
  • Brain Infarction / pathology
  • Brain Infarction / physiopathology
  • Disease Models, Animal
  • Disease Progression
  • Heart Rate / physiology
  • Hypoxia-Ischemia, Brain / complications
  • Hypoxia-Ischemia, Brain / physiopathology*
  • Ischemic Preconditioning / methods*
  • Male
  • Rats
  • Rats, Wistar
  • Reflex, Abnormal / physiology
  • Time Factors