Overexpression of human endothelial nitric oxide synthase in rat vascular smooth muscle cells and in balloon-injured carotid artery.
Endothelial cells in normal blood vessels might prevent the unscheduled proliferation of smooth muscle cells (SMCs) by the expression of cell migration and growth inhibitors. NO, a potent vasodilator, generated by endothelium-specific constitutive NO synthase (ecNOS) might be such an inhibitor. To test this hypothesis, we overexpressed human ecNOS in syngeneic rat arterial SMCs using retrovirus-mediated gene transfer. Compared with SMCs transduced with vector alone (LXSN SMCs), DNA synthesis and cell proliferation were inhibited in the ecNOS-expressing SMCs (LCNSN SMCs). Basal and stimulated (by the calcium ionophore A23187) secretion of NO and intracellular cGMP were increased in LCNSN SMCs. Nomega-Nitro-L-arginine (L-NA), an inhibitor of NO synthesis, enhanced the proliferation of LCNSN SMCs but had no effect on LXSN SMCs. LCNSN SMCs seeded onto the luminal surface of balloon-injured rat carotid arteries inhibited neointimal formation by 37% and induced marked dilatation (3-fold increase in vessel diameter) at 2 weeks compared with LXSN SMC-seeded arteries. Orally administered L-NA blocked these changes. Phosphorylation of vasodilator-stimulated phosphoprotein, which is regulated in part by NO, was elevated in LCNSN SMCs and in LCNSN SMC-seeded arteries. This study demonstrates that NO generation by ecNOS inhibits SMC proliferation in vitro and modulates vascular tone locally in vivo.
Chen
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L
Department of Surgery, University of Washington, Seattle 98195, USA. lihua@u.washington.edu
Daum
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G
Forough
R
R
Clowes
M
M
Walter
U
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Clowes
A W
AW
D000800:Angioplasty, Balloon; D000818:Animals; D001011:Aorta; D000001:Calcimycin / Q000494:pharmacology; D002339:Carotid Arteries / Q000166:cytology / Q000502:physiology*; D020212:Carotid Artery Injuries; D015815:Cell Adhesion Molecules / Q000378:metabolism; D002455:Cell Division; D002478:Cells, Cultured; D006152:Cyclic GMP / Q000378:metabolism; D004730:Endothelium, Vascular / Q000201:enzymology*; D018014:Gene Transfer Techniques; D006801:Humans; D007150:Immunohistochemistry; D007527:Isoenzymes / Q000096:biosynthesis; D007700:Kinetics; D008297:Male; D008840:Microfilament Proteins / Q000378:metabolism; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000293:injuries / Q000502:physiology*; D019001:Nitric Oxide Synthase / Q000096:biosynthesis*; D052250:Nitric Oxide Synthase Type III; D019335:Nitroarginine / Q000494:pharmacology; D010750:Phosphoproteins / Q000378:metabolism; D051381:Rats; D011916:Rats, Inbred F344; D011994:Recombinant Proteins / Q000096:biosynthesis; D012190:Retroviridae; D014162:Transfection; D000098662:Vasodilator-Stimulated Phosphoprotein
D015815:Cell Adhesion Molecules; D007527:Isoenzymes; D008840:Microfilament Proteins; D010750:Phosphoproteins; D011994:Recombinant Proteins; D000098662:Vasodilator-Stimulated Phosphoprotein; D019335:Nitroarginine; D000001:Calcimycin; C496314:NOS3 protein, human; D019001:Nitric Oxide Synthase; D052250:Nitric Oxide Synthase Type III; C496316:Nos3 protein, rat; D006152:Cyclic GMP