bFGF release is dependent on flow conditions in experimental vein grafts.
OBJECTIVE
Basic Fibroblastic Growth Factor (bFGF) is a powerful mitogen for smooth muscle cells and has been implicated in the genesis of Myointimal hyperplasia. The aim of this study was to determine the release of bFGF by veins in different haemodynamic conditions.


METHODS
Laboratory animal study.


METHODS
In 39 Lewis rats, a 1 cm long segment of inferior vena cava was inserted at the level of the abdominal aorta. The segments of inferior vena cava were obtained from syngenic Lewis rats. Arterial Vein Grafts (AVG) were harvested after 4 weeks (AVG 4) and 12 weeks (AVG 12). In 16 animals the arterial vein grafts were explanted 4 weeks after the initial operation and reimplanted (Reimplanted Vein Grafts: RVG) in syngenic Lewis rats as venous-venous bypass grafts at the level of the left iliac vein and harvested after 2 weeks (RVG 2) and 8 weeks (AVG 8).


METHODS
The tissue was studied in organ culture in a serum-free system for (1) release of bFGF (immunoassay) and (2) mitogenic activity of the conditioned media. Scanning electron and light microscopy studies were also performed.


RESULTS
bFGF release by veins increased significantly (p < 0.01) when veins were inserted in the arterial circulation, and decreased significantly (p < 0.01) when grafts were reimplanted in the venous system. bFGF release (ng/cm2): [Formula: see text]


CONCLUSIONS
Vein inserted in the arterial circulation release a higher quantity of bFGF. This could explain in part, the formation of myointimal hyperplasia in arterial vein graft.
D000818:Animals; D001012:Aorta, Abdominal / Q000601:surgery; D017077:Culture Media, Conditioned / Q000032:analysis / Q000378:metabolism; D016895:Culture Media, Serum-Free; D004797:Enzyme-Linked Immunosorbent Assay; D016222:Fibroblast Growth Factor 2 / Q000032:analysis / Q000378:metabolism*; D006965:Hyperplasia / Q000473:pathology; D007084:Iliac Vein / Q000601:surgery; D008297:Male; D008855:Microscopy, Electron, Scanning; D008934:Mitogens / Q000032:analysis / Q000378:metabolism; D009131:Muscle, Smooth, Vascular / Q000473:pathology; D009924:Organ Culture Techniques; D051381:Rats; D011917:Rats, Inbred Lew; D012092:Replantation; D013997:Time Factors; D017539:Tunica Intima / Q000473:pathology; D014682:Vena Cava, Inferior / Q000378:metabolism* / Q000473:pathology / Q000637:transplantation*
D017077:Culture Media, Conditioned; D016895:Culture Media, Serum-Free; D008934:Mitogens; D016222:Fibroblast Growth Factor 2