Limb ischemic preconditioning mitigates lung injury induced by haemorrhagic shock/resuscitation in rats.

Abstract

AIM OF THE STUDY:

Haemorrhagic shock and subsequent resuscitation induce acute lung injury. We elucidated whether bilateral lower limb ischemic pre-conditioning (IP) could mitigate lung injury in haemorrhagic shock/resuscitation rats. The role of heme oxygenase-1 (HO-1) was also elucidated.

METHOD:

Adult male rats were randomized to receive haemorrhagic shock/resuscitation (HS), HS plus IP, or HS plus IP plus the HO-1 inhibitor tin protoporphyrin (SnPP) (n = 12 in each group). Sham groups were employed simultaneously. For pre-conditioning, 3 cycles of limb IP (10 min ischemia followed by 10 min reperfusion) were performed immediately before haemorrhagic shock. Haemorrhagic shock (mean arterial pressure: 40-45 mmHg) was induced by blood drawing and maintained for 120 min. SnPP was injected 5 min before resuscitation. Shed blood/saline mixtures were re-infused to achieve resuscitation. After monitoring for another 8h, rats were sacrificed. Arterial blood gas and alveolar-arterial oxygen difference (lung function index), histology, polymorphonuclear leukocytes/alveoli ratio (leukocyte infiltration index), wet/dry weight ratio (water content index), inflammatory molecules (e.g., chemokine, cytokine, prostaglandin E(2)), and malondialdehyde (lipid peroxidation index) assays were preformed.

RESULTS:

Haemorrhagic shock/resuscitation induced significant lung function alterations and significant increases in leukocyte infiltration, water content, inflammation, and lipid peroxidation in lungs. Histological analysis confirmed that haemorrhagic shock/resuscitation caused marked lung injury. Limb IP significantly mitigated the adverse effects of haemorrhagic shock/resuscitation. Moreover, the protective effects of limb IP were reversed by SnPP.

CONCLUSIONS:

Limb IP mitigates lung injury in haemorrhagic shock/resuscitation rats. The mechanisms may involve HO-1.

• Authors: Woan-Ching Jan, Cay-Huyen Chen, Pei-Shan Tsai, Chun-Jen Huang
• Journal: Resuscitation (Resuscitation) Vol. 82 Issue 6 Pg. 760-6 (Jun 2011) ISSN: 1873-1570 [Electronic] Ireland
• PMID: 21398019 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Topics

• Animals
• Hindlimb (blood supply)
• Ischemic Preconditioning
• Lung Injury (etiology, prevention & control)
• Male
• Rats
• Rats, Sprague-Dawley
• Resuscitation (adverse effects)
• Shock, Hemorrhagic (complications)