Hypoxic vasoconstriction in buffer-perfused rabbit lungs

https://doi.org/10.1016/0034-5687(94)00133-KGet rights and content

Abstract

Isolated rabbit lungs were buffer-perfused under constant flow-conditions with separate control of alveolar (PAO2) and mixed venous (PV̄O2) O2 tension. Alveolar hypoxia caused an increase in pulmonary artery pressure (PAP) with sigmoidal dose-dependency. Erythrocytes increased the strength of the hypoxic pulmonary vasoconstriction (HPV). The contractile and vasorelaxant responses to the onset and release of alveolar hypoxia, respectively, occurred within seconds. Kinetics of the PAP increase, but not the magnitude of response, were related to the velocity of PAO2 decline. In contrast, changes in PV̄O2, both in the absence and presence of erythrocytes, did neither provoke any pressor response nor amplify the response to concomitant alveolar hypoxia. Repeatedly performed HPV manoeuvres revealed excellent reproducibility, and long-term alveolar hypoxia (90 min) provoked a biphasic pressor response. We conclude that the isolated rabbit lung is a feasible model for the characterization of hypoxic vasoconstriction, with specific features hitherto not described for perfused lungs of other species.

References (24)

  • A. Hauge

    Hypoxia and pulmonary vascular resistance

    The relative effects of pulmonary arterial and alveolar PO2

    Acta Physiol. Scand.

    (1969)
  • K.S. Jensen et al.

    Rapid onset of hypoxic vasoconstriction in isolated lungs

    J. Appl. Physiol.

    (1992)
  • Cited by (76)

    • Mitochondrial oxygen sensing of acute hypoxia in specialized cells - Is there a unifying mechanism?

      2022, Biochimica et Biophysica Acta - Bioenergetics
      Citation Excerpt :

      HPV is initiated at mild hypoxia and shows specific dynamic features. In investigations in the model of the isolated, buffer-perfused and ventilated rabbit lung, HPV was detected at a pO2 below 40–75 mmHg in the ventilated gas [11], and in PASMC at a pO2 of 25–50 mmHg in the buffer [7,8]. In humans, HPV was detected at an end-expiratory pO2 of 50 mmHg [23].

    • Hypoxia and the integrated stress response promote pulmonary hypertension and preeclampsia: Implications in drug development

      2021, Drug Discovery Today
      Citation Excerpt :

      Both are low-pressure, high-flow systems [5,6]. Upon exposure to acute hypoxia, systemic arteries and arterioles dilate, whereas pulmonary and uteroplacental arteries and arterioles constrict, leading to increased vascular resistance and reduced blood flow [7,8]. Pulmonary hypertension is a disorder of pulmonary arteries, characterized by a mean pulmonary arterial pressure ≥ 20 mm Hg [9].

    • Hypoxia induces K <inf>v</inf> channel current inhibition by increased NADPH oxidase-derived reactive oxygen species

      2012, Free Radical Biology and Medicine
      Citation Excerpt :

      The unique feature of pulmonary circulation is its ability to contract in response to hypoxia. This ability of the lung vasculature helps in minimizing ventilation perfusion mismatch by diverting blood flow from poorly to well ventilated regions of the lung [1,2]. This phenomenon is known as hypoxic pulmonary vasoconstriction (HPV) [3].

    • Hypoxia-induced changes in pulmonary and systemic vascular resistance: Where is the O<inf>2</inf> sensor?

      2010, Respiratory Physiology and Neurobiology
      Citation Excerpt :

      A large number of studies have examined the responses to hypoxia in the pulmonary and systemic circulations. In the lung, the HPV response is retained in excised lungs, in lung slices, and in PA rings studied in an organ bath (Archer et al., 1993; Desireddi et al., 2010; Grimminger et al., 1995; Leach et al., 2001; Marshall et al., 1996; McMurtry, 1984; Robertson et al., 2001; Rounds and McMurtry, 1981; Weissmann et al., 1998, 1995; Zhao et al., 1996). Isolated PA smooth muscle cells (PASMC) also contract under hypoxia, indicating that these cells are O2-sensitive (Lu et al., 2009; Shimoda et al., 2007; Waypa et al., 2001, 2002, 2006, 2010; Zhang et al., 1997).

    • The Pulmonary Vasculature

      2023, Seminars in Respiratory and Critical Care Medicine
    View all citing articles on Scopus
    1

    Portion of a doctoral thesis at the University of Giessen.

    View full text