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Updated: May 15, 2026
Multiple Intravenous Bolus Dosing and Invasive Hemodynamic Assessment in a Hypoxia-Induced Mouse Pulmonary Artery Hypertension Model
Published on: November 11, 2022
Hemoglobin infusion does not alter murine pulmonary vascular tone
Arkadi Beloiartsev1, David M Baron, Binglan Yu
1Postdoctoral Fellow, Anesthesia Center for Critical Care Research of the Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114-2696, USA.
Intravenous cell-free hemoglobin infusion did not alter pulmonary vascular tone or hypoxic pulmonary vasoconstriction in mice. Nitric oxide (NO) scavenging by plasma hemoglobin is unlikely responsible for low pulmonary vascular tone in mice.
Area of Science:
- Physiology
- Cardiovascular Research
- Pulmonary Circulation
Background:
- Plasma hemoglobin (Hb) scavenges nitric oxide (NO), potentially causing vasoconstriction.
- Hypoxic pulmonary vasoconstriction (HPV) is a critical physiological response.
- The role of plasma Hb in regulating pulmonary vascular tone in mice is not fully understood.
Purpose of the Study:
- To investigate the effect of cell-free Hb administration on basal pulmonary vascular tone in mice.
- To determine if plasma Hb enhances hypoxic pulmonary vasoconstriction (HPV) in mice.
- To explore the role of nitric oxide (NO) in mediating these effects.
Main Methods:
- Intravenous infusion of murine cell-free Hb in anesthetized wild-type and diabetic mice.
- Measurement of left lung pulmonary vascular resistance (LPVRI), right ventricular systolic pressure (RVSP), and systemic arterial pressure (SAP).
- Assessment of HPV during regional lung hypoxia induced by left mainstem bronchial occlusion (LMBO) before and after Hb pretreatment or L-NAME administration.
Main Results:
- Hb infusion increased systemic arterial pressure but did not affect pulmonary arterial pressure or LPVRI in wild-type or diabetic mice.
- Plasma Hb did not alter HPV in wild-type mice.
- Inhibition of NO synthase with L-NAME augmented HPV but did not change basal LPVRI.
Conclusions:
- Plasma Hb scavenging of NO does not alter basal pulmonary vascular tone in mice.
- The findings suggest NO generation in the pulmonary circulation is not responsible for the low basal pulmonary vascular tone observed in mice.
- These results provide insights into the mechanisms regulating pulmonary vascular tone and HPV in mice.
