Adenoviral-mediated transfer of the human endothelial nitric oxide synthase gene reduces acute hypoxic pulmonary vasoconstriction in rats.
Nitric oxide (NO), a vasodilator involved in the regulation of pulmonary vascular tone, is synthesized by a family of enzymes, nitric oxide synthases (NOS). To investigate whether adenoviral-mediated overexpression of constitutive endothelial NOS (ceNOS) would attenuate hypoxic pulmonary vasoconstriction, we aerosolized 3 X 10(9) plaque forming units of a recombinant adenovirus containing the ceNOS gene (AdCMVceNOS) into rat lungs. Four days after infection, transgene expression was confirmed using immunoblot techniques. Diffuse ceNOS immunostaining was detected in alveoli and medium-sized and small pulmonary vessels of AdCMVceNOS-transduced lungs. AdCMVceNOS-transduction was associated with an 86% increase in [3H]arginine to [3H]citrulline conversion and a rise in pulmonary cGMP levels from 7 +/- 1 to 59 +/- 9 pmol/mg protein in lungs from AdCMVceNOS versus control rats, (P < 0.05). During acute hypoxia (FIO2 = 0.10) for 25 min, mean pulmonary artery pressure (PAP) increased significantly from 17 +/- 1 to 27 +/- 1 mmHg in rats aerosolized with saline (n = 4) and from 18 +/- 1 to 28 +/- 1 mmHg in rats given an adenoviral vector expressing a nuclear-targeted beta-galactosidase gene (AdCMV beta gal, n = 8). In contrast, in AdCMVceNOS-transduced rats (n = 8) the hypoxia-induced increase in PAP was significantly attenuated (18 +/- 1 to 23 +/- 2 mmHg). Systemic blood pressure was not affected by aerosol gene transfer. Thus, adenoviral-mediated ceNOS gene transfer to rat lungs increases ceNOS expression and activity, and reduces acute hypoxic pulmonary vasoconstriction. Aerosolized recombinant adenovirus overexpressing vasodilatory proteins can act as a selective pulmonary vasodilator and may hold promise as a future therapeutic strategy for pulmonary hypertension.
Janssens
S P
SP
Cardiac Unit, University of Leuven and Flanders Interuniversity Institute for Biotechnology, Belgium.
Bloch
K D
KD
Nong
Z
Z
Gerard
R D
RD
Zoldhelyi
P
P
Collen
D
D
D000256:Adenoviridae; D000704:Analysis of Variance; D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D003587:Cytomegalovirus; D017931:DNA Primers; D004730:Endothelium, Vascular / Q000201:enzymology*; D018014:Gene Transfer Techniques; D005822:Genetic Vectors; D006801:Humans; D000860:Hypoxia; D007150:Immunohistochemistry; D007700:Kinetics; D008168:Lung / Q000098:blood supply / Q000502:physiology*; D008969:Molecular Sequence Data; D019001:Nitric Oxide Synthase / Q000032:analysis / Q000096:biosynthesis* / Q000235:genetics; D016133:Polymerase Chain Reaction; D011652:Pulmonary Circulation / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D015183:Restriction Mapping; D014661:Vasoconstriction
D017931:DNA Primers; D019001:Nitric Oxide Synthase