Exogenous nitric oxide inhibits in vivo platelet adhesion following balloon angioplasty.
OBJECTIVE
The aim was to investigate the effects of an exogenous source of nitric oxide on in vivo platelet adhesion at the site of endothelial denudation after balloon angioplasty.


METHODS
The study group consisted of 12 anaesthetised Large White pigs. Pigs were randomised to receive SIN-1 (3-morpholino-sydnonimine), an exogenous donor of nitric oxide, or placebo before and during balloon induced vessel wall injury. Platelet deposition was quantified using the injection of autologous 111indium labelled platelets. Platelet function was also monitored by the measurement of bleeding time and ex vivo whole blood aggregometry.


RESULTS
Superficial vessel wall injury was confirmed histologically and platelet monolayer formation was demonstrated by scanning electron microscopy. Platelet deposition at the site of endothelial denudation was markedly reduced following SIN-1 administration compared to placebo: 1.266(SEM 0.063) v 1.732(0.060) log platelets x 10(5).cm-2, p = 0.001. SIN-1 raised platelet cyclic GMP concentration, from 4.47(2.48) to 6.14(2.44) pg.platelet-1 (p less than 0.01) and prolonged the bleeding time, from 135(5) to 202(6) s (p = 0.001), but had non-significant effects on ex vivo whole blood aggregometry.


CONCLUSIONS
Exogenous nitric oxide, through the activation of platelet soluble guanylate cyclase, inhibits platelet adhesion in vivo following balloon angioplasty.
Groves
P H
PH
University of Wales College of Medicine, Heath Park, Cardiff, United Kingdom.
Penny
W J
WJ
Cheadle
H A
HA
Lewis
M J
MJ
D000800:Angioplasty, Balloon; D000818:Animals; D001792:Blood Platelets / Q000187:drug effects / Q000378:metabolism; D002339:Carotid Arteries / Q000502:physiology; D004730:Endothelium, Vascular / Q000502:physiology; D008981:Molsidomine / Q000031:analogs & derivatives* / Q000494:pharmacology; D009569:Nitric Oxide / Q000494:pharmacology*; D010973:Platelet Adhesiveness / Q000187:drug effects*; D011184:Postoperative Period; D013552:Swine
D009569:Nitric Oxide; C002385:linsidomine; D008981:Molsidomine