Pretreatment with Tongxinluo protects porcine myocardium from ischaemia/reperfusion injury through a nitric oxide related mechanism.

Abstract

BACKGROUND:

The traditional Chinese medicine Tongxinluo can protect myocardium against ischaemia/reperfusion injury, but the mechanism of its action is not well documented. We examined the involvement of nitric oxide in the protective role of Tongxinluo.

METHODS:

Miniswine were randomized to four groups of seven: sham, control, Tongxinluo and Tongxinluo coadministration with a nitric oxide synthase inhibitor N(omega)-nitro-L-arginine (L-NNA, 10 mg/kg i.v.). Three hours after administration of Tongxinluo, the animals were anaesthetised and the left anterior descending coronary artery ligated and maintained in situ for 90 minutes followed by 3 hours of reperfusion before death. Area of no reflow and necrosis and risk region were determined pathologically by planimetry. The degree of neutrophil accumulation in myocardium was obtained by measuring myeloperoxidase activity and histological analysis. Myocardial endothelial nitric oxide synthase activity and vascular endothelial cadherin content were measured by colorimetric method and immunoblotting analysis respectively.

RESULTS:

Tongxinluo significantly increased the local blood flow and limited the infarct and size of no reflow. Tongxinluo also attenuated myeloperoxidase activity and neutrophil accumulation in histological sections and maintained the level of vascular endothelial cadherin and endothelial nitric oxide synthase activity in the reflow region when compared with control group. The protection of Tongxinluo was counteracted by coadministration with L-NNA.

CONCLUSIONS:

Tongxinluo may limit myocardial ischaemia and protect the heart against reperfusion injury. Tongxinluo regulates synthesis of nitric oxide by altering activity of endothelial nitric oxide synthase.

• Authors: Yu-tong Cheng, Yue-jin Yang, Hai-tao Zhang, Hai-yan Qian, Jing-lin Zhao, Xian-min Meng, Fu-liang Luo, Yi-ling Wu
• Journal: Chinese medical journal (Chin Med J (Engl)) Vol. 122 Issue 13 Pg. 1529-38 (Jul 05 2009) ISSN: 2542-5641 [Electronic] China
• PMID: 19719943 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antigens, CD
• Cadherins
• Drugs, Chinese Herbal
• cadherin 5
• tongxinluo
• Nitric Oxide
• Peroxidase
• Nitric Oxide Synthase

Topics

• Animals
• Antigens, CD (analysis)
• Blood Pressure (drug effects)
• Cadherins (analysis)
• Drugs, Chinese Herbal (therapeutic use)
• Heart Rate (drug effects)
• Microscopy, Fluorescence
• Myocardial Infarction (drug therapy, physiopathology)
• Myocardial Reperfusion Injury (prevention & control)
• Myocardium (enzymology, pathology)
• Neutrophil Infiltration
• Nitric Oxide (physiology)
• Nitric Oxide Synthase (metabolism)
• Peroxidase (metabolism)
• Swine
• Swine, Miniature