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Videomorphometric Analysis of Hypoxic Pulmonary Vasoconstriction of Intra-pulmonary Arteries Using Murine Precision Cut Lung Slices
Published on: January 14, 2014
Lung capillaries raise the hypoxia alarm
1Division of Pulmonary, Allergy and Critical Care, Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, New York 10032, USA. jb39@columbia.edu
The Journal of Clinical Investigation
|October 25, 2012
Summary
The lung uses hypoxic pulmonary vasoconstriction (HPV) to maintain blood oxygenation during blocked ventilation. New research shows the lung
Area of Science:
- Pulmonary medicine
- Cardiovascular physiology
- Respiratory system
Background:
- The lung protects blood oxygenation via hypoxic pulmonary vasoconstriction (HPV) when ventilation is impaired.
- HPV redirects blood flow from poorly ventilated to well-ventilated alveoli.
- The precise mechanism of hypoxic signaling in HPV has been unclear.
Purpose of the Study:
- To elucidate the signaling pathway responsible for initiating hypoxic pulmonary vasoconstriction (HPV).
- To identify the cellular components involved in sensing alveolar hypoxia and triggering HPV.
Main Methods:
- Investigated the role of the alveolar endothelium in hypoxic signaling.
- Utilized experimental models to study the transmission of hypoxic signals.
Main Results:
- The endothelial lining of hypoxic alveoli is crucial for sensing low oxygen levels.
- This endothelial sensing mechanism transmits the signal to initiate arteriolar smooth muscle contraction.
- Wang et al. identified key components in the endothelial cell's role in HPV.
Conclusions:
- The endothelial cells in the lung's alveoli are critical sensors of hypoxia.
- Endothelial cells play a central role in transmitting the signal that initiates hypoxic pulmonary vasoconstriction (HPV).
- This finding clarifies a long-standing mystery regarding the mechanism of HPV.
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