What question did this study set out to answer?

To measure diameter changes in small pulmonary arteries and veins in response to hypoxia and serotonin across varying levels of arteriovenous pressure elevation.

January 1, 1994Journal of Applied Physiology

Influence of hypoxia and serotonin on small pulmonary vessels

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Authors

AAAmir AltinawiKing Saud Medical City GKGary S. KrenzMarquette University DRD. A. RickabyMedical College of Wisconsin

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Implication

Experimental study reveals differential arterial and venous constriction from hypoxia and serotonin in isolated dog lungs, indicating microvessels heavily drive total pulmonary resistance.

Key Points

To measure diameter changes in small pulmonary arteries and veins in response to hypoxia and serotonin across varying levels of arteriovenous pressure elevation.
Used X-ray angiograms of isolated perfused canine lungs to measure internal diameter changes of small intraparenchymal arteries (150–1,600 µm) and veins (200–1,000 µm).
Applied hypoxia or intra-arterial serotonin (5-HT) infusions across a range of stimulus-induced arteriovenous pressure drops (ΔPa).
At small ΔPa, both stimuli constricted all studied arteries, causing maximum diameter decreases of ~25% with hypoxia and ~36% with 5-HT; at large ΔPa, arteries >800 µm distended under hypoxia, whereas 5-HT caused constriction across all arterial sizes.
Hypoxia induced an approximately 9% constriction in all examined pulmonary veins regardless of diameter or ΔPa, whereas 5-HT exerted no significant effect on venous caliber.
Resistance modeling indicated that while vessels 150–1,600 µm in size contributed significantly, microvessels smaller than 150 µm also generated a major portion of total pulmonary vascular resistance.

Cite This Study

Altinawi et al. (1994) studied this question.

synapsesocial.com/papers/6a951b6c8ce716a7e9fa6236 https://doi.org/10.1152/jappl.1994.76.1.56

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Implication

Experimental study reveals differential arterial and venous constriction from hypoxia and serotonin in isolated dog lungs, indicating microvessels heavily drive total pulmonary resistance.

Influence of hypoxia and serotonin on small pulmonary vessels

Discussion

Member takes

Implication

Key Points

Cite This Study

Influence of hypoxia and serotonin on small pulmonary vessels

Discussion

Member takes

Implication

Key Points

Cite This Study

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