Pulmonary Vascular Resistance and Impedance in Isolated Mouse Lungs: Effects of Pulmonary Emboli
- 28 March 2006
- journal article
- Published by Springer Science and Business Media LLC in Annals of Biomedical Engineering
- Vol. 34 (4), 660-668
- https://doi.org/10.1007/s10439-005-9050-z
Abstract
To study pulsatile pressure-flow rate relationships in the intact pulmonary vascular network of mice, we developed a protocol for measuring pulmonary vascular resistance and impedance in isolated, ventilated, and perfused mouse lungs. We used pulmonary emboli to validate the effect of vascular obstruction on resistance and impedance. Main pulmonary artery and left atrial pressures and pulmonary vascular flow rate were measured under steady and pulsatile conditions in the lungs of C57BL/6J mice (n = 6) before and after two infusions with 25 μm-diameter microspheres (one million per infusion). After the first and second embolizations, pulmonary artery pressures increased approximately two-fold and three and a half-fold, respectively, compared to baseline, at a steady flow rate of 1 ml/min (P < 0.05). Pulmonary vascular resistance and 0 Hz impedance also increased after the first and second embolizations for all flow rates tested (P < 0.05). Frequency-dependent features of the pulmonary vascular impedance spectrum were suggestive of shifts in the major pulmonary vascular reflection sites with embolization. Our results demonstrate that pulmonary artery pressure, resistance, and impedance magnitude measured in this isolated lung setup changed in ways consistent with in vivo studies in larger animals and humans and demonstrate the usefulness of the isolated, ventilated, and perfused mouse lung for investigating steady and pulsatile pressure-flow rate relationships.Keywords
This publication has 25 references indexed in Scilit:
- Attenuation of acute hypoxic pulmonary vasoconstriction and hypoxic pulmonary hypertension in mice by inhibition of Rho-kinaseAmerican Journal of Physiology-Lung Cellular and Molecular Physiology, 2004
- Altered Pulmonary Vascular Reactivity in Mice with Excessive ErythrocytosisAmerican Journal of Respiratory and Critical Care Medicine, 2004
- Hemodynamic effects of 15-μm-diameter microspheres on the rat pulmonary circulationJournal of Applied Physiology, 2000
- Relative contributions of endothelial, inducible, and neuronal NOS to tone in the murine pulmonary circulationAmerican Journal of Physiology-Lung Cellular and Molecular Physiology, 1999
- O 2 sensing is preserved in mice lacking the gp91 phox subunit of NADPH oxidaseProceedings of the National Academy of Sciences of the United States of America, 1999
- Comparison of the effects of isoflurane with those of propofol on pulmonary vascular impedance in experimental embolic pulmonary hypertension.British Journal of Anaesthesia, 1997
- Pulmonary vascular pressure-flow characteristics in canine pulmonary embolismJournal of Applied Physiology, 1990
- Pulmonary artery constriction produces a greater right ventricular dynamic afterload than lung microvascular injury in the open chest dog.Circulation Research, 1985
- Pulmonary Vascular Impedance in the DogCirculation Research, 1965
- The relation of pulsatile pressure and flow in the pulmonary vascular bedThe Journal of Physiology, 1961