Diabetes mellitus and experimental vein graft structure and function.
OBJECTIVE
Diabetes mellitus is a known risk factor for accelerated atherosclerosis and for postangioplasty restenosis.


METHODS
This study examines the effect of chronic, uncontrolled, alloxan-induced diabetes on the structure and vasomotor function of vein bypass grafts in 20 male New Zealand white rabbits with diabetes and in 10 controls. After 8 weeks of diabetes, a common carotid vein bypass graft was performed. Four weeks after operation, vein grafts and contralateral jugular veins were harvested.


RESULTS
Diabetes induced a twofold increase in the vein graft intimal thickness compared with control. There was no change in medial thickness. Electron microscopy of the vein grafts in diabetes revealed intercellular gaps in the endothelium lining and abnormal endothelial cell junctions compared with controls. Diabetes significantly increased the maximal contractions generated in vein grafts to all contractile agonists tested without any change in sensitivity.


CONCLUSIONS
This study demonstrates that diabetes alters endothelial cell structure and increases the development of intimal hyperplasia with increased maximal contractility in vein grafts and therefore suggests that the vein grafts in diabetes are more susceptible to early stenosis.
Davies
M G
MG
Department of Surgery, Duke University Medical Center, Durham, NC 27710.
Kim
J H
JH
Klyachkin
M L
ML
Barber
L
L
Dalen
H
H
Svendsen
E
E
Carson
C C
CC
Hagen
P O
PO
D000818:Animals; D001161:Arteriosclerosis / Q000097:blood / Q000503:physiopathology / Q000601:surgery; D001786:Blood Glucose / Q000032:analysis; D017536:Carotid Artery, Common / Q000601:surgery*; D003921:Diabetes Mellitus, Experimental / Q000097:blood / Q000503:physiopathology / Q000601:surgery*; D003925:Diabetic Angiopathies / Q000097:blood / Q000503:physiopathology / Q000601:surgery*; D004195:Disease Models, Animal; D004730:Endothelium, Vascular / Q000648:ultrastructure; D007601:Jugular Veins / Q000503:physiopathology / Q000637:transplantation* / Q000648:ultrastructure; D008297:Male; D008855:Microscopy, Electron, Scanning; D011817:Rabbits
D001786:Blood Glucose