Prostoglandin Bx (PGBx) is an oligmer of Prostaglandin Bl. The dimer and trimer have been shown to protect various tissues, including hepatic, renal, cerebral, and cardiac, from loss of function after ischemia. It is thought that the drug stabilizes mitochondrial membranes, and protects the mitochondria from loss of oxidative phosphorylation. A total of 85 rat hearts have been given Prostaglandin Bx (PGBx) during ischemia while on the isolated heart apparatus. Each heart received between 40-200 micrograms of PGBx, either at the beginning of the ischemic interval or at the time of reperfusion. The ischemic time was 27 minutes at 37.5 degrees C. The control group received no PGBx. Forty-six percent of the control hearts survived the ischemic period. The treated hearts had survival rates ranging from 38% to 100%. The difference was significant in only one of the treated groups. There were no differences in the percent recovery of systolic pressure, aortic flow, cardiac output or stroke volume between the control and treated groups. The treated animals had a significantly lower recovery of heart rate compared to the treated animals. The conclusion was that PGBx had little if any myocardial protective effect.
