Da. Margolin et al., INCREASED PLATELET-DERIVED GROWTH-FACTOR PRODUCTION AND INTIMAL THICKENING DURING HEALING OF DACRON GRAFTS IN A CANINE MODEL, Journal of vascular surgery, 17(5), 1993, pp. 858-867
Purpose: Growth factor production by endothelial cells on grafts may p
lay a role in the development of intimal hyperplasia and subsequent gr
aft failure. Methods: To study the relationship between platelet-deriv
ed growth factor production and graft healing, 26 beagles underwent pl
acement of 20 cm long, 6 mm internal diameter, knitted Dacron thoracoa
bdominal grafts, either seeded with autologous endothelial cells (n =
14) or unseeded controls (n = 12). The grafts and adjacent arteries we
re removed 4 or 20 weeks after implantation for measurement of platele
t-derived growth factor production in organ culture, endothelial cell
coverage, and intimal thickness. Results. Midgraft platelet-derived gr
owth factor production by seeded graft segments increased from 41 +/-
6 to 148 +/- 27 pg/cm2/72 hr (p < 0.002) between 4 and 20 weeks. This
was accompanied by a significant increase in inner-capsule thickness.
Platelet-derived growth factor production by control graft segments al
so increased from 58 +/- 21 to 163 +/- 42 pg (p < 0.05) and was simila
r to that of seeded grafts despite more rapid endothelialization of se
eded grafts. The increase in growth factor production by Dacron grafts
was greater than that of the expanded polytetrafluoroethylene grafts
studied previously despite similar endothelial cell coverage. Conclusi
on: This increase corresponded with the rapid appearance of smooth mus
cle cells in the pseudointima of Dacron grafts, suggesting that these
cells may be responsible for the observed increase in platelet-derived
growth factor production.