Role of macrophages in myocardial apoptosis following cardiac transplant. Influence of immunosuppressive treatment.

Cytotoxic T cells may induce myocardial apoptosis by histiocyte activation during rejection following allogenic heart transplant. The aim of the present investigation was to evaluate the macrophage response and its relationship to the programmed death of cardiomyocytes in rejection and during cyclosporin-A (CsA) treatment. An abdominal, heterotopic heart transplant rat model was used establishing two groups: singenic (ST) and allogenic (AL) transplant.

Effects of ischaemia-reperfusion and cyclosporin-A on cardiac muscle ultrastructure.

The present study investigates the effects on the cardiac muscle cell of two of the determining factors for the success of organ transplant; ischaemia-perfusion and immunosuppressive treatment with cyclosporin-A (CsA). To this end an abdominal, heterotopic heart transplant model in singenic Sprague-Dawley rats was employed. Three study groups were established: Group I (control, n = 15) animals undergoing heart transplant without treatment; Group II (n = 15) animals undergoing heart transplant and subjected to a daily dose of CsA in a cremophor vehicle (Sandimun) (5 mg/kg/sc); Group III (n = 15): animals undergoing heart transplant and administered a daily dose of pure CsA (5 mg/kg/sc).

Intimal thickening in arterial autografts. Role of the adventitial layer.

In the present work, the repairing response of the iliac arterial wall is studied after carrying out autografts in segments of these vessels. The formation of the intimal hyperplasia, which occurred in all the cases, was followed at the biochemical level (tritium thymidine incorporation) and with light and electron microscopy. The adventitial layer showed great activity during the repairing process.

Role of 201Tl in the management of cardiac transplantation.

Serial percutaneous endomyocardial biopsy is the standard for diagnosis of cardiac rejection; it is generally done on a weekly basis for the first month and then as indicated by ECG voltage; but, this method is invasive, can be done only in specialized centers, not available for the many patients who return home, requires 18-24 h before a result is obtained, delaying institution of therapy, and it is aggressive for the endomyocardium of the graft. A reliable, rapid, and noninvasive test for detection of cardiac rejection is still not available. The aim of this work was to determine whether 201Tl uptake was significantly correlated with the histological findings presenting in cardiac rejection.