Intratracheal adenoviral-mediated delivery of iNOS decreases pulmonary vasoconstrictor responses in rats.
We hypothesized that adenovirus-mediated inducible nitric oxide synthase (iNOS) gene transduction of the lung would result in time-dependent iNOS overexpression and attenuate the vascular constrictor responses to a thromboxane mimetic, U-46619. Rats were treated via the trachea with surfactant alone (sham), surfactant containing an adenoviral construct with a cytomegalovirus promoter-regulated human iNOS gene (Adeno-iNOS), or an adenoviral construct without a gene insert (Adeno-Control). Adeno-iNOS-transduced rats demonstrated human iNOS mRNA and increased iNOS protein levels only in the lungs. Immunohistochemistry of lungs from Adeno-iNOS-treated animals demonstrated transgene expression in alveolar wall cells. In the lungs from Adeno-iNOS-transduced rats, the expression of iNOS protein and exhaled nitric oxide concentrations were increased on days 1-4 and 7 but returned to baseline values by day 14. The administration of the selective iNOS inhibitor L-N6-(1-iminoethyl)lysine dihydrochloride (L-NIL) decreased exhaled nitric oxide concentrations to levels found in Adeno-Control-transduced lungs. In a second group of rats, the segmental vasoconstrictor responses to U-46619 were determined in isolated, perfused lungs 3 days after transduction. Lungs from rats transduced with Adeno-iNOS had reduced total, arterial, and venous vasoconstrictor responses to U-46619 compared with sham, Adeno-Control, and control groups. In a third set of experiments, the response to 400 nM U-46619 in the presence of 10 microM L-NIL was not different in the isolated lungs from Adeno-Control- and Adeno-iNOS-transduced rats. We conclude that adenovirus-mediated iNOS gene transduction of the lung results in time-dependent iNOS overexpression, which attenuates the vascular constrictor responses to the thromboxane mimetic U-46619.
Chicoine
Louis G
LG
Department of Pediatrics, University of New Mexico Health Sciences Center, Albuquerque, New Mexico 87131, USA. chicoinl@pediatrics.ohio-state.edu
Tzeng
Edith
E
Bryan
Rebekah
R
Saenz
Steven
S
Paffett
Michael L
ML
Jones
Joelle
J
Lyons
C Richard
CR
Resta
Thomas C
TC
Nelin
Leif D
LD
Walker
Benjimen R
BR
D019796:15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid / Q000494:pharmacology; D000256:Adenoviridae; D000818:Animals; D004305:Dose-Response Relationship, Drug; D045853:Exhalation; D005822:Genetic Vectors; D006801:Humans; D007158:Immunologic Techniques; D066298:In Vitro Techniques; D008168:Lung / Q000378:metabolism; D008297:Male; D009569:Nitric Oxide; D019001:Nitric Oxide Synthase / Q000008:administration & dosage* / Q000235:genetics / Q000378:metabolism / Q000494:pharmacology; D052247:Nitric Oxide Synthase Type II; D011652:Pulmonary Circulation / Q000187:drug effects*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013194:Staining and Labeling; D013997:Time Factors; D014018:Tissue Distribution; D014132:Trachea; D014161:Transduction, Genetic / Q000379:methods; D014655:Vascular Resistance / Q000187:drug effects; D014661:Vasoconstriction / Q000187:drug effects*; D014662:Vasoconstrictor Agents / Q000494:pharmacology
D014662:Vasoconstrictor Agents; D009569:Nitric Oxide; D019796:15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid; C496319:NOS2 protein, human; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; C496318:Nos2 protein, rat