IMMEDIATE-EARLY GENE-EXPRESSION IN HUMAN SAPHENOUS VEINS HARVESTED DURING CORONARY-ARTERY BYPASS GRAFT OPERATIONS

Saphenous vein graft occlusion is a common late complication of corona ry bypass grafting. Intimal smooth muscle cell hyperplasia is a compon ent of this pathobiology, but the underlying molecular events are poor ly understood. Immediate-early genes are activated shortly after growt h stimulation and subserve cellular functions, which may contribute to intimal smooth muscle cell accumulation. In the present study, human saphenous vein grafts were harvested with minimal manipulation during coronary bypass and processed for isolation of total ribonucleic acid to examine changes in immediate-early gene expression of messenger rib onucleic acid by Northern blotting techniques. Thirty saphenous vein g rafts were incubated at 4 degrees C in Dulbecco's modified Eagle media from 30 minutes to 10 hours. The messenger ribonucleic acids for imme diate-early genes c-fos and c-myc were weak or undetectable in control s but were increased (>10 times controls) within 1 hour (c-fos) and pe rsisted for at least 6 hours (c-myc) after harvest. Our results demons trate, for the first time in human vascular tissue, incipient immediat e-early gene induction. This information may lead to molecular therapi es to control saphenous vein graft disease.