The plateau zokor (Eospalax baileyi) is an underground dwelling rodent species native to the Tibetan plateau (2000-4200 meters in elevation). A new study published in the American Journal of Physiology – Regulatory, Integrative and Comparative Physiology explored how these animals were adapted to extract oxygen from an environment with very low levels (83-88% of atmospheric).
Hemoglobin molecules found in red blood cells are responsible for binding oxygen and transporting it to tissues throughout the body. Cold environments and increases in carbon dioxide promote the release of oxygen molecules to help keep tissues oxygenated. In this new study, the research team demonstrated that hemoglobin molecules from plateau zokor are strongly attracted to oxygen and are able to hang on to it even in their cold underground environment (-7.8 to 10 °C) marked by high carbon dioxide levels (7.3 to 48.6 times higher than atmospheric). Another adaptation of this remarkable species is the development of larger lungs with more blood vessels to assist in the extraction of oxygen from their environment in addition to larger hearts to pump blood more efficiently.
If only mountain climbers could be more like these rodents.
P Pu, S Lu, Z Niu, T Zhang, Y Zhao, X Yang, Y Zhao, X Tang, Q Chen. Oxygenation properties and underlying molecular mechanisms of hemoglobin in plateau zokor (Eospalax baileyi). American Journal of Physiology – Regulatory, Integrative and Comparative Physiology. In press, 2019. https://doi.org/10.1152/ajpregu.00335.2018