Oxygen affinity of hemoglobin regulates O2 consumption, metabolism, and physical activity.
The oxygen affinity of hemoglobin is critical for gas exchange in the lung and O(2) delivery in peripheral tissues. In the present study, we generated model mice that carry low affinity hemoglobin with the Titusville mutation in the alpha-globin gene or Presbyterian mutation in the beta-globin gene. The mutant mice showed increased O(2) consumption and CO(2) production in tissue metabolism, suggesting enhanced O(2) delivery by mutant Hbs. The histology of muscle showed a phenotypical conversion from a fast glycolytic to fast oxidative type. Surprisingly, mutant mice spontaneously ran twice as far as controls despite mild anemia. The oxygen affinity of hemoglobin may control the basal level of erythropoiesis, tissue O(2) consumption, physical activity, and behavior in mice.
Shirasawa
Takuji
T
Department of Molecular Gerontology, Tokyo Metropolitan Institute of Gerontology, Itabashi-ku, Tokyo 173-0015, Japan. sirasawa@tmig.or.jp
Izumizaki
Masahiko
M
Suzuki
Yo-ichi
Y
Ishihara
Akihiko
A
Shimizu
Takahiko
T
Tamaki
Masakatsu
M
Huang
Fei
F
Koizumi
Ken-ichi
K
Iwase
Michiko
M
Sakai
Hiromi
H
Tsuchida
Eishun
E
Ueshima
Kenji
K
Inoue
Hiroshi
H
Koseki
Haruhiko
H
Senda
Toshiya
T
Kuriyama
Takayuki
T
Homma
Ikuo
I
D000818:Animals; D006454:Hemoglobins / Q000235:genetics / Q000378:metabolism*; D008297:Male; D051379:Mice; D018345:Mice, Knockout; D009154:Mutation; D010100:Oxygen / Q000378:metabolism*; D010101:Oxygen Consumption; D010641:Phenotype; D010805:Physical Conditioning, Animal / Q000502:physiology*; D011485:Protein Binding
D006454:Hemoglobins; D010100:Oxygen