Objective To develop miniature pig model of coronary microembolization (CME) by easy and cost-effi-cient technique. Methods A total of 11 miniature pigs were divided into control group (n=5) and CME group (n=6). Femo-ral artery was punctured using 21 gauge needle that is normally used for transradial procedures. Microspheres were injected into the left anterior descending artery of the CME group by 5 F coronary radiography catheter and 1.8 F coronary micro-guide catheter. Serum concentrations of brain natriuretic peptide (BNP) and cardiac troponin I (cTnI) were evaluated just be-fore CME and 6 hours after CME. Apical myocardial pathological lesions were evaluated by optical microscope 6 hours after CME. Results All miniature pigs in control group survived, but one died in the CME group. 5 F coronary radiography cathe-ter and 1.8 F coronary micro-guide catheter reached designated location successfully. Before CME, serum BNP (ng/L:143.00 ± 13.51 vs 134.00 ± 15.57) and cTnI (μg/L:0.39 ± 0.09 vs 0.38 ± 0.10) showed no significant differences between these two groups (t values are 0.976 and 0.294 respectively,both P>0.05). By contrast, serum BNP (561.00 ± 80.65) and cTnI (2.75±0.58) were much higher in CME group than those (BNP 139.00±13.87;cTnI 0.54±0.14 ) in control group after CME (t values are 11.530 and 8.337 respectively,both P＜0.001). In CME group, microspheres, micro-infarction and inflammatory cell infiltration were seen under an optical microscope which are absent in control group. Conclusion Using new surgical consumables can successfully develop miniature pig model with CME. And the technique is simple, cost-efficient, practical so it is worth promoting.

To study the effects of different pH HEPES-KH reperfusate solution on immature myocardial protection, isolated perfused Langendorff model from immature rabbit hearts were developed formed. Control group (C) was perfused only with pH 7.4 HEPES-KH solution for 90 min. Ischemia/reperfusion group (group I/R) was perfused with pH 7.4 HEPES-KH solution before ischemia or after ischemia. Experimental group (group E), after ischemia, was perfused with pH 6.8, pH 7.1 and pH 7.4 HEPES-KH solutions for 5 min, 5 min, and 20 min, respectively. The left ventricular function recovery, MWC, LDH and CK leakage, MDA, ATP content, and SOD activity were determined. Our results showed that the left ventricular function recovery, ATP content and SOD activity in group E were higher than those of group I/R (P < 0.05). MWC, MDA content, LDH and CK leakage in group E were lower than those of group I/R (P < 0.05). These findings suggested that pH paradox might be one of important mechanisms for immature myocardial ischemia-reperfusion injury, and acidic perfusate, at the beginning of reperfusion, might attenuate pH paradox and ameliorate functional recovery in isolated perfused immature rabbit hearts.
Myocardium/metabolism ; Random Allocation ; Superoxide Dismutase/metabolism

To study the effects of different pH HEPES-KH reperfusate solution on immature myocardial protection, isolated perfused Langendorff model from immature rabbit hearts were developed formed. Control group (C) was perfused only with pH 7.4 HEPES-KH solution for 90 min. Ischemia/reperfusion group (group I/R) was perfused with pH 7.4 HEPES-KH solution before ischemia or after ischemia. Experimental group (group E), after ischemia, was perfused with pH 6.8, pH 7.1 and pH 7.4 HEPES-KH solutions for 5 min, 5 min, and 20 min, respectively. The left ventricular function recovery, MWC, LDH and CK leakage, MDA, ATP content, and SOD activity were determined. Our results showed that the left ventricular function recovery, ATP content and SOD activity in group E were higher than those of group I/R (P < 0.05). MWC, MDA content, LDH and CK leakage in group E were lower than those of group I/R (P < 0.05). These findings suggested that pH paradox might be one of important mechanisms for immature myocardial ischemia-reperfusion injury, and acidic perfusate, at the beginning of reperfusion, might attenuate pH paradox and ameliorate functional recovery in isolated perfused immature rabbit hearts.
Animals ; Cardioplegic Solutions ; pharmacology ; Female ; Heart ; physiopathology ; Heart Arrest, Induced ; Hydrogen-Ion Concentration ; Male ; Myocardial Ischemia ; metabolism ; physiopathology ; Myocardial Reperfusion Injury ; metabolism ; physiopathology ; prevention & control ; Myocardium ; metabolism ; Rabbits ; Random Allocation ; Superoxide Dismutase ; metabolism