Endothelial cell induced modulation of cardiac fibroblast collagen metabolism

Objective: The aim was to examine the influence of vascular endothelial cells on rat cardiac fibroblast collagen synthesis and collagenase activity under co-culture conditions, and to determine whether angiotensin II or aldosterone influence endothelial cell induced modulation of fibroblast collagen metabolism. Methods: Bovine aortic endothelial cells were grown to confluence on microporous membrane inserts and then co-cultured with cardiac fibroblasts obtained from adult rats, previously grown to confluence in 35 mm dishes supplemented with 0.4% fetal bovine serum. Collagen synthesis was measured by 3H-proline incorporation. Experiments were also conducted under similar conditions to quantitate collagenase activity by zymography in conditioned medium from fibroblasts co-cultured with endothelial cells. Results: After 48 h co-culture, there was a 1.9-fold increase in fibroblast collagen synthesis when compared to fibroblasts alone (p