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Vulnerability of the developing heart to oxygen deprivation as a cause of congenital heart defects.

Kenchegowda D, Liu H, Thompson K, Luo L, Martin SS, Fisher SA - J Am Heart Assoc (2014)

Bottom Line: The heart develops under reduced and varying oxygen concentrations, yet there is little understanding of oxygen metabolism in the normal and mal-development of the heart.ODD-Luc activity decreased in 2 stages, the first corresponding with the formation of a functional cardiovascular system for oxygen delivery at E15.5, and the second after birth consistent with complete oxygenation of the blood and tissues.Low oxygen concentrations and lack of oxygen reserve during a critical phase of heart organogenesis may provide a basis for vulnerability to the development of common septation and conotruncal heart defects.

View Article: PubMed Central - PubMed

Affiliation: Department of Cardiovascular Medicine, University of Maryland School of Medicine, Baltimore, MD (D.K., S.A.F.).

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Related in: MedlinePlus

Bioluminescent imaging of E13.5 ODD‐Luc embryo. Pregnant mice were injected i.p. with d‐luciferin (150 mg/kg) and embryos removed and imaged 15 minutes later in the supine position with a high sensitivity charged coupled device camera (Xenogen IVIS‐200) as described in Methods. A representative embryo from n=6 is shown with (A) low power and (B) high power images and (C) regions of interest with bioluminescent signal intensity shown. Scale bar shows range of signal from the field of view in photons sec−1 (cm2)−1 sr−1. D and E, are the corresponding bright field images. F, Mean±SEM of signals from n=6 embryos. Within the heart the bioluminescent signal is ≈200‐fold above background and highest within the OFT. *P<0.001 vs ventricle. All values are significantly above background (P<0.001; Student t test). Scale bars 500 μm. LV indicates left ventricle; ODD‐Luc, oxygen degradation domain‐luciferase; OFT, outflow tract; RV, right ventricle.
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fig02: Bioluminescent imaging of E13.5 ODD‐Luc embryo. Pregnant mice were injected i.p. with d‐luciferin (150 mg/kg) and embryos removed and imaged 15 minutes later in the supine position with a high sensitivity charged coupled device camera (Xenogen IVIS‐200) as described in Methods. A representative embryo from n=6 is shown with (A) low power and (B) high power images and (C) regions of interest with bioluminescent signal intensity shown. Scale bar shows range of signal from the field of view in photons sec−1 (cm2)−1 sr−1. D and E, are the corresponding bright field images. F, Mean±SEM of signals from n=6 embryos. Within the heart the bioluminescent signal is ≈200‐fold above background and highest within the OFT. *P<0.001 vs ventricle. All values are significantly above background (P<0.001; Student t test). Scale bars 500 μm. LV indicates left ventricle; ODD‐Luc, oxygen degradation domain‐luciferase; OFT, outflow tract; RV, right ventricle.

Mentions: Bioluminescent imaging was used to determine the spatial distribution of ODD‐Luc activity in the E13.5 embryo. The substrate luciferin was administered to the pregnant mice and the embryos removed and imaged as described in Methods. Robust bioluminescent signal was observed in the ODD‐Luc embryos (Figure 2) while no activity was observed in wild type embryos or in ODD‐Luc mice in the absence of luciferin. The activity in the E13.5 heart was ≈200‐fold above background, similar to that measured in tissue homogenates. Within the heart a gradient of bioluminescent signal was observed with the outflow region of the heart exhibiting ≈50% greater signal as compared to the ventricles (Figures 2B, 2C, and 2F; P<0.001).


Vulnerability of the developing heart to oxygen deprivation as a cause of congenital heart defects.

Kenchegowda D, Liu H, Thompson K, Luo L, Martin SS, Fisher SA - J Am Heart Assoc (2014)

Bioluminescent imaging of E13.5 ODD‐Luc embryo. Pregnant mice were injected i.p. with d‐luciferin (150 mg/kg) and embryos removed and imaged 15 minutes later in the supine position with a high sensitivity charged coupled device camera (Xenogen IVIS‐200) as described in Methods. A representative embryo from n=6 is shown with (A) low power and (B) high power images and (C) regions of interest with bioluminescent signal intensity shown. Scale bar shows range of signal from the field of view in photons sec−1 (cm2)−1 sr−1. D and E, are the corresponding bright field images. F, Mean±SEM of signals from n=6 embryos. Within the heart the bioluminescent signal is ≈200‐fold above background and highest within the OFT. *P<0.001 vs ventricle. All values are significantly above background (P<0.001; Student t test). Scale bars 500 μm. LV indicates left ventricle; ODD‐Luc, oxygen degradation domain‐luciferase; OFT, outflow tract; RV, right ventricle.
© Copyright Policy - creative-commons
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4309110&req=5

fig02: Bioluminescent imaging of E13.5 ODD‐Luc embryo. Pregnant mice were injected i.p. with d‐luciferin (150 mg/kg) and embryos removed and imaged 15 minutes later in the supine position with a high sensitivity charged coupled device camera (Xenogen IVIS‐200) as described in Methods. A representative embryo from n=6 is shown with (A) low power and (B) high power images and (C) regions of interest with bioluminescent signal intensity shown. Scale bar shows range of signal from the field of view in photons sec−1 (cm2)−1 sr−1. D and E, are the corresponding bright field images. F, Mean±SEM of signals from n=6 embryos. Within the heart the bioluminescent signal is ≈200‐fold above background and highest within the OFT. *P<0.001 vs ventricle. All values are significantly above background (P<0.001; Student t test). Scale bars 500 μm. LV indicates left ventricle; ODD‐Luc, oxygen degradation domain‐luciferase; OFT, outflow tract; RV, right ventricle.
Mentions: Bioluminescent imaging was used to determine the spatial distribution of ODD‐Luc activity in the E13.5 embryo. The substrate luciferin was administered to the pregnant mice and the embryos removed and imaged as described in Methods. Robust bioluminescent signal was observed in the ODD‐Luc embryos (Figure 2) while no activity was observed in wild type embryos or in ODD‐Luc mice in the absence of luciferin. The activity in the E13.5 heart was ≈200‐fold above background, similar to that measured in tissue homogenates. Within the heart a gradient of bioluminescent signal was observed with the outflow region of the heart exhibiting ≈50% greater signal as compared to the ventricles (Figures 2B, 2C, and 2F; P<0.001).

Bottom Line: The heart develops under reduced and varying oxygen concentrations, yet there is little understanding of oxygen metabolism in the normal and mal-development of the heart.ODD-Luc activity decreased in 2 stages, the first corresponding with the formation of a functional cardiovascular system for oxygen delivery at E15.5, and the second after birth consistent with complete oxygenation of the blood and tissues.Low oxygen concentrations and lack of oxygen reserve during a critical phase of heart organogenesis may provide a basis for vulnerability to the development of common septation and conotruncal heart defects.

View Article: PubMed Central - PubMed

Affiliation: Department of Cardiovascular Medicine, University of Maryland School of Medicine, Baltimore, MD (D.K., S.A.F.).

Show MeSH
Related in: MedlinePlus