raffinose and Ventricular-Dysfunction--Left

We tested the hypothesis that pretreatment with the antioxidant probucol attenuates reperfusion-induced diastolic abnormalities in the heterotopic rat cardiac isograft.. American Cancer Institute rats (n = 48) were divided into 6 groups. Hearts were arrested by coronary perfusion with 3 ml 4 degrees C University of Wisconsin solution at 60 mmHg. Eighteen donor hearts were divided into 3 groups of 6 and arrested either 1 hour after intraperitoneal injection of 3 ml oil with (Prob Tx) or without (Oil Tx) probucol (300 mg/kg) or without injection (Ctrl Tx). After a 90 minute storage period, abdominal isografting was performed with a total ischemic time of 2 hours. Following 15 minutes of blood reperfusion, donor hearts were rearrested and excised. Recipients' native hearts (NH, n = 18) were also arrested. Two additional groups with (Prob NR, n = 6) and without (Ctrl NR, n = 6) probucol pretreatment were arrested and subjected to 2 hours of ischemia without reperfusion. Postmortem LV pressure-volume curves and myocardial water content (MWC) were measured.. At each pressure interval normalized LV volume (LVV) was significantly greater for Prob Tx than Oil Tx or Ctrl Tx. All isograft groups had significantly lower LVV at all pressure intervals and higher MWC than non-transplanted hearts.. Pretreatment with probucol attenuates reperfusion-induced decreases in LVV in the heterotopic rat heart isograft model. Probucol, which is orally active in humans, merits further study for its potential to improve myocardial protection during cardiac surgery.

Topics: Abdomen; Adenosine; Allopurinol; Animals; Antioxidants; Body Water; Cardiac Volume; Glutathione; Heart Transplantation; Injections, Intraperitoneal; Insulin; Myocardial Reperfusion Injury; Organ Preservation Solutions; Organ Size; Probucol; Raffinose; Rats; Transplantation, Heterotopic; Transplantation, Isogeneic; Ventricular Dysfunction, Left; Ventricular Pressure

Studies of myocardial edema and diastolic dysfunction in rat heart transplantation have been flawed by ischemic injury. This study uses improved methods to prevent ischemic contracture.. Hearts of 30 ACI rats were transplanted into the abdomen of Lewis rats by use of cold University of Wisconsin solution for improved preservation. Left ventricular diastolic properties were expressed as volume at standardized pressure intervals.. On posttransplantation day 3, mean left ventricular volume at 15 mm Hg in allografts (290 +/- 9 microl, SEM) was not significantly different vs isografts (299 +/- 32 microl), allografts on day 0 (337 +/- 28 ml) or day 1 (324 +/- 20 microl), or native hearts (334 +/- 19 microl). However, volume was reduced to 173 +/- 17 microl on day 4 and to 70 +/- 23 microl on day 5 (p < 0.05). Similar findings were obtained for volume at 5 and 10 mm Hg. Allograft myocardial water content on day 3, 76.3% +/- 5%, similar to allografts on day 0 and 1 and to isografts on day 3, increased to 77.6% +/- 8% on day 4 (NS) and 79.4% +/- 6% on day 5 (p < 0.05 vs day 0). Histologically, rejection in allografts was mild on day 3, moderate on day 4, and severe on day 5.. Reduced left ventricular filling volume during rejection is only partially explained by edema. Abnormalities of diastolic properties previously attributed to the unloaded state of nonworking heart models may actually reflect inadequate peritransplantation myocardial protection.

Topics: Adenosine; Allopurinol; Animals; Cardiomyopathies; Cardioplegic Solutions; Diastole; Edema; Glutathione; Graft Rejection; Heart Transplantation; Insulin; Male; Organ Preservation; Organ Preservation Solutions; Raffinose; Rats; Rats, Inbred ACI; Rats, Inbred Lew; Transplantation, Heterotopic; Ventricular Dysfunction, Left