Protective effects of betaglucin on myocardial tissue during myocardial infarction in rats and dogs.
OBJECTIVE
To test the protective effects of betaglucin, a novel beta-glucan, on models of myocardial infarction (MI) in rats and dogs.


METHODS
The left anterior descending (LAD) coronary artery occlusion model was used to induce an MI in rats and dogs. Three doses of betaglucin (10, 30 and 100 mg/kg), propranolol (positive control, 1 mg/kg) and vehicle alone (5% glucose solution) were administered before LAD occlusion, and characteristics of the resulting MI were subsequently assessed. In anesthetized dogs, blood pressure, heart rate, ventricular function, coronary artery blood flow and myocardial oxygen consumption were determined before and after the drug administration.


RESULTS
The MI mass in both rats and dogs was significantly reduced by betaglucin (30 and 100 mg/kg, P<0.01) and propranolol (P<0.01). In anesthetized dogs, coronary artery blood flow was increased significantly by betaglucin (30 and 100 mg/kg, P<0.01), but blood pressure, heart rate and ventricular function were not changed (P>0.05). High-dose betaglucin (100 mg/kg) increased myocardial oxygen consumption, but not to a statistically significant level (P>0.05). The hemodynamic indexes were significantly changed by propranolol.


CONCLUSIONS
Betaglucin has protective effects on myocardial tissue during MI in rats and dogs and has no influence on hemodynamic parameters at a therapeutic dose. The increase in coronary artery blood flow induced by betaglucin might be beneficial in the treatment of patients with MI.
Qian
Jiao
J
Department of Pharmacology, School of Pharmacy, Second Military Medical University, Shanghai 200433, China.
Liu
Ai-jun
AJ
Zhang
Wei
W
Wen
Zhi-peng
ZP
Lin
Li-li
LL
Wang
Jing-hang
JH
Su
Ding-feng
DF
Liu
Jian-guo
JG
D000818:Animals; D001783:Blood Flow Velocity / Q000187:drug effects; D001794:Blood Pressure / Q000187:drug effects; D002316:Cardiotonic Agents / Q000627:therapeutic use*; D003331:Coronary Vessels / Q000187:drug effects / Q000503:physiopathology; D004285:Dogs; D005260:Female; D006321:Heart / Q000187:drug effects / Q000503:physiopathology; D006339:Heart Rate / Q000187:drug effects; D008297:Male; D009203:Myocardial Infarction / Q000188:drug therapy* / Q000503:physiopathology*; D010101:Oxygen Consumption / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D016276:Ventricular Function / Q000187:drug effects; D047071:beta-Glucans / Q000627:therapeutic use*
D002316:Cardiotonic Agents; D047071:beta-Glucans; C544425:betaglucin