Objective: Angiotensin I Converting Enzyme was used to study the inhibitory activity of porcine placenta extracts.
Methods: ACE was derived from rabbit lung. Bz-Gly-His-Leu was used as a substrate. Production of hippuric acid was measured by HPLC.
Result: ACE inhibitory activity was measured in a two-fold dilution of porcine placenta extracts. The IC₅₀ of porcine placenta extracts was 95.7 μg. The results of a Lineweaver-Burk plot suggested that porcine placenta extracts exhibited a competitive inhibition.
Conclusion: In this paper, we found that porcine placenta extracts had an anti-ACE activity.

Controlled Freezing-point Storage (CF Storage) is a new method of preserving foods in minus non-frozen temperature range. So, we tried to apply this method to entrails preservation and investigated the effect of controlled freezing-point storage of hearts on ventricular function in isolated perfused rat heart (male, Sprague dawley strain, in body about 300g weight). The hearts were perfused by working heart mode for 10min, and received infusion of cardioplegic solution which was followed by 4 hours of cardiac arrest at a myocardial temperature 4°C (4°C group) or minus non-frozen temperature (CF storage group). Then, the aerobic reperfusion by working heart mode was continued for an additional 30min. The recovery rate of cardiac output was 33.5% and 62.5% respectively of the preischemic value in 4°C group and CF storage group, which was statistically significant (p<0.01). ATP activity after 4 hours of cardiac arrest in 4°C group was significantly lower than that in CF storage group (p<0.05). These data suggest that CF storage of hearts might have a protective effect against an ischemic insult upon myocardial cell during hypothermic cardiac arrest.

IABP is in wide clinical use as an effective adjunctive means for the management of seriously impaired cardiac function. Unfortunately, however, it is an undeniable fact that this specialized circulatory support technic has so far been used in severe heart disease cases in a desultory way, with no established criteria being available for indication of elective IABP for prophylactic purposes. Under such circumstances, it was felt worthwhile to analyze data on preoperative left ventricular function from a series of open heart surgery cases (25 treated with and 94 without IABP) encountered in our hospital since 1983 (when procedure for myocardial protection was virtually standardized) in an effort to formulate acceptable criteria for indication of elective IABP. Hemodynamic parameters studied were LVESVI, LVEF and LVEDP. The results led us to conclude that scheduled IABP can be regarded as indicated for use in each of the following valvular heart diseases if at least one of the respective criteria specified below is fulfilled: MR: LVESVI≥120ml/m², LVEF≤0.4, LVEDP≥21mmHg; AR: LVESVI≥135ml/m², LVEF≤0.4, LVEDP≥18mmHg; MS: LVESVI≥70ml/m², LVEF≤0.35, LVEDP≥23mmHg.