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Cardiovascular Adaptation in Response to Chronic Hypoxia in Awake Rats

  • Saki Hamashima
  • Masahiro ShibataEmail author
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 876)

Abstract

To examine how cardiovascular adaptation to chronic hypoxia might evolve, the responses to blood pressure (Pt) and hematocrit (Ht) during long-term systemic exposure to hypoxia were observed in awake rats. Furthermore, the total peripheral vascular resistance (TPR) was estimated using direct measurements of systemic blood pressure (Ps) and blood flow (Qs) in carotid artery based on Darcy’s law (TPR = Ps/Qs) to evaluate the remodeling procedure in the microcirculation. BP and Ht under normoxic conditions were kept almost constant, while hypoxic exposure immediately increased Ht to 58 % and, thereafter, it remained stable. The TPR values showed no significant differences between hypoxic and normoxic conditions. These results suggest that effects of high viscosity caused by increasing Ht on peripheral vascular resistance can be compensated by inducing microvascular remodeling with the arteriolar dilation and capillary angiogenesis.

Keywords

Hypoxia Total peripheral vascular resistance Microvascular remodelling Awake rats 

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Copyright information

© Springer Science+Business Media, New York 2016

Authors and Affiliations

  1. 1.Department of Bioscience and EngineeringShibaura Institute of TechnologyTokyoJapan

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