Mg. Davies et al., THE INFLUENCE OF THE COMBINED PRESENCE OF DIABETES-MELLITUS AND HYPERCHOLESTEROLEMIA ON THE FUNCTION AND MORPHOLOGY OF EXPERIMENTAL VEIN GRAFTS, European journal of vascular and endovascular surgery, 10(2), 1995, pp. 142-155
Objectives: Diabetes and hypercholesterolaemia are known risk factors
for the development of atherosclerosis and are considered to influence
the development of vein graft intimal hyperplasia. This study examine
s the combined effect of diabetes for 12 weeks (alloxan-induced) and h
ypercholesterolaemia for 8 weeks (1% cholesterol diet) on the formatio
n of intimal hyperplasia and the vasomotor function of vein grafts. Ma
terials and design: Thirty-two New Zealand White rabbits underwent a c
arotid vein bypass graft. Eight were controls, eight were diabetic, ei
ght were hypercholesterolaemic and eight had both diabetes and hyperch
olesterolaemia. All vein grafts were harvested at 4 weeks postoperativ
ely for morphology (n = 4) or contractility studies (n = 4). Results:
Compared to controls, both diabetes and hypercholesterolaemia increase
d intimal thickness by 20% and 63% respectively; medial thicknesses of
these vein grafts were unchanged compared to control. In contrast, di
abetes with hypercholesterolaemia dramatically increased intimal and m
edial thicknesses (1.8 fold and 1.6 fold respectively, compared to con
trol). Smooth muscle cell contractility was enhanced in both the diabe
tic and hypercholesterolaemic groups, The presence of diabetes with hy
percholesterolaemia did not further alter the enhanced smooth muscle c
ell contractile responses. Conclusions: This study suggests that the c
ombination of both the atherogenic risk factors, hypercholesterolaemia
and diabetes, significantly augments the formation of intimal hyperpl
asia in experimental vein grafts.