The protective effects of tetrahydroprotoberberines (THPB), viz., l-tetrahydropalmatine (THP), l-stepholidine (SPD), and tetrahydroberberine (THB) on experimental myocardial infarction by ligating the left coronary artery were estimated in rats. The myocardial infarction size (MIS) was determined by
The effects of tetrahydroberberine (THB) on ischemic and reperfused myocardium were studied in comparison with verapamil (Ver). In anesthetized rats, THB and its analogues, l-THP and l-SPD, reduced the infarct size after 4 h of left anterior descending coronary artery (LAD) ligation. In Langendorff