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Polycythemia and Changes in Erythropoietin Concentration in Rats Exposed to Intermittent Hypoxia

  • Makoto Ishii
  • Tokuzen Iwamoto
  • Asuka Nagai
  • Gen Sasao
  • Masayuki Iwasaki
  • Ichiro Kuwahira
Conference paper
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 662)

Abstract

It is not clear whether blood hemoglobin concentration ([Hb]) increases with an increase in the exposure period of intermittent hypoxia (IHx) and reaches a constant level. Furthermore, it is not known whether plasma erythropoietin concentration ([EPO]) also increases with an increase in the exposure period. Using a rat model, first, we evaluated changes in [EPO] every hour after single exposure of 10% O2 for 120 min in order to determine a peak level of [EPO]. Second, we evaluated the effect of IHx of 10% O2, 120 min/day for 0 (control), 1, 2, 3, 4, 6 and 8 weeks on [Hb], arterial blood pressure (BP), heart rate (HR), arterial blood gases (ABGs) and [EPO]. [EPO] increased after cessation of the single hypoxic exposure, reached a peak at 1 h, and decreased gradually to the control levels within 18 h. IHx of 10% O2, 120 min/day, produced a time-dependent increase in [Hb], and [Hb] reached a constant level after the exposure for 6 weeks. BP increased after the exposure for 4 weeks and remained elevated. There was no significant difference in HR and ABGs. [EPO] increased significantly and remained elevated at the same level for 1–3 weeks, however, the peak level of [EPO] declined markedly after [Hb] reached a constant level.

Keywords

Obstructive Sleep Apnea Syndrome Intermittent Hypoxia Hypoxic Exposure Halothane Anesthesia Normobaric Hypoxia 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Notes

Acknowledgments

The skillful technical assistance of Katsuko Naito, Yoko Takahari, and Yoshiko Shinozaki is gratefully acknowledged. This study was supported, in part, by the Ministry of Education, Science, Sports and Culture, Japan, Grant-in-Aid for Exploratory Research (No. 20659133, 2008).

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Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  • Makoto Ishii
    • 1
  • Tokuzen Iwamoto
    • 2
  • Asuka Nagai
    • 1
    • 2
  • Gen Sasao
    • 2
  • Masayuki Iwasaki
    • 3
  • Ichiro Kuwahira
    • 1
    • 2
  1. 1.Department of MedicineTokai University School of MedicineIseharaJapan
  2. 2.Department of MedicineTokai University Tokyo HospitalTokyoJapan
  3. 3.Department of General Thoracic SurgeryTokai University School of MedicineIseharaJapan

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