Mechanisms for hypoxia detection in O2-sensitive cells.
Since O(2) is the bare necessity for multicellular organisms, they develop multiple protective mechanisms against hypoxia. Mammals will adapt to hypoxia in short and long terms. The short-term responses include enhancement of the respiratory and cardiac functions, adrenaline secretion from adrenal medullary cells, and pulmonary vasoconstriction, whereas the long-term response is the increase in erythropoietin production with the consequent increase in red blood cells. Although much work has been done to elucidate molecular mechanisms for O(2)-sensing for the last ten years, the majority of the mechanisms remain unclear. We will review mechanisms proposed for hypoxia detection in carotid body type I cells, pulmonary artery smooth muscle, adrenal medullary cells, and liver cells, with the special focus on adrenal medullary cells.
Fujishiro
Naoji
N
Department of Cell and System Physiology, University of Occupational and Environmental Health School of Medicine, Kitakyushu, 807-8555 Japan.
Endo
Yutaka
Y
Warashina
Akira
A
Inoue
Masumi
M
D000222:Adaptation, Physiological; D000313:Adrenal Medulla / Q000166:cytology* / Q000502:physiology*; D002118:Calcium / Q000378:metabolism; D002344:Carotid Body / Q000166:cytology / Q000502:physiology; D015687:Cell Hypoxia; D006801:Humans; D008099:Liver / Q000166:cytology* / Q000502:physiology*; D008928:Mitochondria / Q000502:physiology; D009130:Muscle, Smooth / Q000166:cytology / Q000502:physiology; D010100:Oxygen / Q000378:metabolism*; D017382:Reactive Oxygen Species
D017382:Reactive Oxygen Species; D010100:Oxygen; D002118:Calcium