Maturation-related changes in endothelial nitric oxide synthase immunolocalization in developing ovine lung

1994 ◽  
Vol 267 (5) ◽  
pp. L585-L591 ◽  
Author(s):  
A. C. Halbower ◽  
R. M. Tuder ◽  
W. A. Franklin ◽  
J. S. Pollock ◽  
U. Forstermann ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Nitric Oxide Synthase ◽  
Pulmonary Circulation ◽  
Endothelial Nitric Oxide Synthase ◽  
Vascular Tone ◽  
Pulmonary Arteries ◽  
Fetal Lung ◽  
Fetal Life ◽  
Oxide Synthase ◽  
Endothelial Nitric Oxide

It is unknown whether high fetal pulmonary vascular tone is due in part to absent or decreased endothelial nitric oxide synthase (eNOS), the enzyme that produces nitric oxide in the vascular endothelium. To determine the timing of appearance and maturational changes of eNOS in the developing pulmonary circulation, we performed immunohistochemistry in lungs from fetal, neonatal, and adult sheep. Using a mouse monoclonal antibody against bovine aortic eNOS, we found immunoreactive eNOS selectively in the endothelium and it was present at all fetal ages. Immunoreactivity was seen as early as 29% gestation in the developing capillaries coursing through fetal mesenchyme. By 6 days after birth, immunoreactivity was decreased in most vessels and nearly absent in the distal pulmonary arteries of adult animals. We conclude that immunoreactive eNOS is present very early in fetal life and appears to decrease postnatally. We speculate that the early presence of eNOS in the fetal lung supports a possible role for endogenous nitric oxide activity in the regulation of vascular tone or angiogenesis in the developing pulmonary circulation.

Heat shock protein 90 modulates endothelial nitric oxide synthase activity and vascular reactivity in the newborn piglet pulmonary circulation

2007 ◽  
Vol 292 (6) ◽  
pp. L1515-L1525 ◽  
Author(s):  
Judy L. Aschner ◽  
Susan L. Foster ◽  
Mark Kaplowitz ◽  
Yongmei Zhang ◽  
Heng Zeng ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Heat Shock ◽  
Nitric Oxide Synthase ◽  
Heat Shock Protein ◽  
Pulmonary Circulation ◽  
Endothelial Nitric Oxide Synthase ◽  
Vascular Reactivity ◽  
Heat Shock Protein 90 ◽  
Oxide Synthase ◽  
Endothelial Nitric Oxide

Heat shock protein 90 (Hsp90) binding to endothelial nitric oxide synthase (eNOS) is an important step in eNOS activation. The conformational state of bound Hsp90 determines whether eNOS produces nitric oxide (NO) or superoxide (O2•−). We determined the effects of the Hsp90 antagonists geldanamycin (GA) and radicicol (RA) on basal and ACh-stimulated changes in vessel diameter, cGMP production, and Hsp90:eNOS coimmunoprecipitation in piglet resistance level pulmonary arteries (PRA). In perfused piglet lungs, we evaluated the effects of GA and RA on ACh-stimulated changes in pulmonary arterial pressure (Ppa) and perfusate accumulation of stable NO metabolites (NOx−). The effects of GA and RA on ACh-stimulated O2•− generation was investigated in cultured pulmonary microvascular endothelial cells (PMVEC) by dihydroethidine (DHE) oxidation and confocal microscopy. Hsp90 inhibition with GA or RA reduced ACh-mediated dilation, abolished the ACh-stimulated increase in cGMP, and reduced eNOS:Hsp90 coprecipitation. GA and RA also inhibited the ACh-mediated changes in Ppa and NOx− accumulation rates in perfused lungs. ACh increased the rate of DHE oxidation in PMVEC pretreated with GA and RA but not in untreated cells. The cell-permeable superoxide dismutase mimetic M40401 reversed GA-mediated inhibition of ACh-induced dilation in PRA. We conclude that Hsp90 is a modulator of eNOS activity and vascular reactivity in the newborn piglet pulmonary circulation. Uncoupling of eNOS with GA or RA inhibits ACh-mediated dilation by a mechanism that involves O2•− generation.

Endothelial nitric oxide synthase gene transfer enhances dilation of newborn piglet pulmonary arteries

1999 ◽  
Vol 277 (1) ◽  
pp. H371-H379
Author(s):  
Judy L. Aschner ◽  
Nora Kovacs ◽  
James V. Perciaccante ◽  
Jorge P. Figueroa ◽  
Nishadi Thrikawala ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Nitric Oxide Synthase ◽  
Gene Transfer ◽  
Endothelial Nitric Oxide Synthase ◽  
Cultured Cells ◽  
Pulmonary Arteries ◽  
Pulmonary Vasculature ◽  
Enos Expression ◽  
Oxide Synthase ◽  
Endothelial Nitric Oxide

We determined the expression and functional correlate of in vitro transfection with a recombinant adenoviral vector encoding the gene for bovine endothelial nitric oxide synthase (AdCMVeNOS) or Escherichia coliβ-galactosidase (AdCMVLacZ) in pulmonary endothelial cells (EC), vascular smooth muscle cells (VSMC), and pulmonary arteries (PA) from newborn piglets. AdCMVeNOS and AdCMVeLacZ vectors, grown in 293-cell monolayers, were purified by double-cesium gradient ultracentrifugation. Cell cultures and PA were incubated with increasing vector titers for 30 or 60 min, followed by incubation in fresh medium for 18 h at 37°C. LacZ expression was assessed by histochemical staining; eNOS expression was evaluated by Western blot analysis. Functional eNOS expression was determined by measurement of cGMP and quantification of the relaxation response to bradykinin (BK). In PA, LacZ transgene expression was preferentially localized to the adventitia and endothelium. Increased eNOS protein expression was observed in EC and VSMC transfected with AdCMVeNOS. Functional studies revealed increased cGMP abundance in cultured cells and enhanced relaxation to BK in AdCMVeNOS-transfected PA. These studies demonstrate that gene transfer with AdCMVeNOS results in functional expression and altered vasoactive responses in the neonatal pulmonary vasculature. Gene transfer with replication-deficient adenovirus vectors is a useful tool for the study of targeted genes in vascular biology.

Abstract 380: Notch4 Uncouples Endothelial Nitric Oxide Synthase Leading to Arteriovenous Malformations

2016 ◽  
Vol 36 (suppl_1) ◽  
Author(s):  
Lawrence Huang ◽  
Matthew A Nystoriak ◽  
Ji Youn Youn ◽  
Manuel F Navedo ◽  
Hua Cai ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Nitric Oxide Synthase ◽  
Notch Signaling ◽  
Endothelial Nitric Oxide Synthase ◽  
Vascular Tone ◽  
Superoxide Production ◽  
Nos Inhibitor ◽  
Av Shunt ◽  
Oxide Synthase ◽  
Endothelial Nitric Oxide

Notch is distinctively expressed in arterial but not venous endothelial cells. Notch signaling regulates arteriovenous (AV) specification, and mutations in Notch signaling lead to AV malformation (AVM) in mice. AVMs are characterized by abnormal AV shunts that displace capillaries. Mechanisms underlying AVM pathogenesis remain poorly understood, hindering therapeutic development. We reported that endothelial expression of constitutively active Notch4 (Notch4*) in mice initiates AVMs de novo through enlargement of microvessels without an increase in endothelial cell number or proliferation. Here, we hypothesized that Notch4* disrupts endothelial nitric oxide synthase (eNOS) signaling and vascular tone, thereby permitting vessel enlargement and AV shunting. We show that arteries isolated from Notch4* mutant mice exhibited decreased arterial tone compared to controls, suggesting that Notch4* impaired vascular tone. Administering the NOS inhibitor N G -nitro-L-arginine abolished Notch4*-mediated vascular tone impairment. Deletion of the eNOS gene and administration of the NOS inhibitor N G -nitro-L-arginine in the Notch4* mutant mice attenuated Notch4*-induced AVM initiation, measured by decreased AV shunt diameter, delayed AV shunting, reduced hemorrhage, pathological lesions, and improved survival, suggesting that eNOS is essential for Notch4* action. In addition, uncoupled eNOS-derived superoxide production was elevated in the Notch4* mice. Our results show that inhibition of eNOS signaling attenuates Notch4*-mediated AVM formation. Furthermore, Notch4* impairs eNOS activity, leading to superoxide production, which results in arterial dysfunction and AV shunt formation.

Reduced endothelial nitric oxide synthase in lungs of chronically ventilated preterm lambs

2001 ◽  
Vol 281 (4) ◽  
pp. L1011-L1020 ◽  
Author(s):  
Amy N. MacRitchie ◽  
Kurt H. Albertine ◽  
Jiancheng Sun ◽  
Paul S. Lei ◽  
Suzanne C. Jensen ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Smooth Muscle ◽  
Nitric Oxide Synthase ◽  
Respiratory Tract ◽  
Chronic Lung Disease ◽  
Pulmonary Circulation ◽  
Endothelial Nitric Oxide Synthase ◽  
Oxide Synthase ◽  
Endothelial Nitric Oxide ◽  
Enos Protein

Nitric oxide (NO), produced in lung vascular endothelium and airway epithelium, has an important role in regulating smooth muscle cell growth and tone. Chronic lung disease, a frequent complication of premature birth, is characterized by excess abundance, tone, and reactivity of smooth muscle in the pulmonary circulation and conducting airways, leading to increased lung vascular and airway resistance. Whether these structural and functional changes are associated with diminished pulmonary expression of endothelial nitric oxide synthase (eNOS) protein is unknown. Both quantitative immunoblot analysis and semiquantitative immunohistochemistry showed that there was less eNOS protein in the endothelium of small intrapulmonary arteries and epithelium of small airways of preterm lambs that were mechanically ventilated for 3 wk compared with control lambs born at term. No significant differences were detected for other proteins (inducible NOS, α-smooth muscle actin, and pancytokeratin). Lung vascular and respiratory tract resistances were greater in the chronically ventilated preterm lambs compared with control term lambs. These results support the notion that decreased eNOS in the pulmonary circulation and respiratory tract of preterm lambs may contribute to the pathophysiology of chronic lung disease.

Reduced Expression of Endothelial Nitric Oxide Synthase in Pulmonary Arteries of Smokers

2001 ◽  
Vol 164 (4) ◽  
pp. 709-713 ◽  
Author(s):  
JOAN A. BARBERÀ ◽  
VICTOR I. PEINADO ◽  
SALUD SANTOS ◽  
JOSEP RAMIREZ ◽  
JOSEP ROCA ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Nitric Oxide Synthase ◽  
Endothelial Nitric Oxide Synthase ◽  
Pulmonary Arteries ◽  
Oxide Synthase ◽  
Endothelial Nitric Oxide

Age-dependent endothelial nitric oxide synthase uncoupling in pulmonary arteries of endoglin heterozygous mice

2009 ◽  
Vol 297 (6) ◽  
pp. L1170-L1178 ◽  
Author(s):  
J. Belik ◽  
M. Jerkic ◽  
B. A. S. McIntyre ◽  
J. Pan ◽  
J. Leen ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Nitric Oxide Synthase ◽  
Endothelial Nitric Oxide Synthase ◽  
Pulmonary Arteries ◽  
Ros Generation ◽  
Type I ◽  
Newborn Mice ◽  
Enos Uncoupling ◽  
Oxide Synthase ◽  
Endothelial Nitric Oxide

Endoglin is a TGF-β superfamily receptor critical for endothelial cell function. Mutations in this gene are associated with hereditary hemorrhagic telangiectasia type I (HHT1), and clinical signs of disease are generally more evident later in life. We previously showed that systemic vessels of adult Eng heterozygous ( Eng+/−) mice exhibit increased vasorelaxation due to uncoupling of endothelial nitric oxide synthase (eNOS). We postulated that these changes may develop with age and evaluated pulmonary arteries from newborn and adult Eng+/− mice for eNOS-dependent, acetylcholine (ACh-induced) vasorelaxation, compared with that of age-matched littermate controls. While ACh-induced vasorelaxation was similar in all newborn mice, it was significantly increased in the adult Eng+/− vs. control vessels. The vasodilatory responses were inhibited by l-NAME suggesting eNOS dependence. eNOS uncoupling was observed in lung tissues of adult, but not newborn, heterozygous mice and was associated with increased production of reactive O2 species (ROS) in adult Eng +/− vs. control lungs. Interestingly, ROS generation was higher in adult than newborn mice and so were the levels of NADPH oxidase 4 and SOD 1, 2, 3 isoforms. However, enzyme protein levels and NADPH activity were normal in adult Eng+/− lungs indicating that the developmental maturation of ROS generation and scavenging cannot account for the increased vasodilatation observed in adult Eng+/− mice. Our data suggest that eNOS-dependent H2O2 generation in Eng+/− lungs accounts for the heightened pulmonary vasorelaxation. To the extent that these mice mimic human HHT1, age-associated pulmonary vascular eNOS uncoupling may explain the late childhood and adult onset of clinical lung manifestations.

Sign in / Sign up

Export Citation Format

Share Document