EXPRESSION OF INSULIN-LIKE GROWTH FACTOR-I BY HUMAN VENTRICULAR EXPLANTS IN CULTURE

There is increasing evidence from animal studies for autocrine and Par acrine systems in the heart. As the local role of these peptide system s in the human heart is not clear, we assessed cardiac explants in cul ture as a model for the study of growth factor expression by the heart in humans. Human right ventricular septal biopsies were maintained as explants for up to 9 days in serum-supplemented medium. Insulin-like growth factor-1 (IGF-1) expression was measured by radioimmunoassay an d results corrected for tissue protein content. IGF-1 was synthesised by ventricular explants but not secreted into the culture medium. This culture model has the potential to provide insight into the regulatio n of and response to growth factor expression by the heart in humans.