Hypobaric-hypoxic exposure and histochemical responses of soleus muscle fibers in the rat.
Hypoxia-acclimatized rats had a higher percentage of fast-twitch oxidative glycolytic fibers and a lower percentage of slow-twitch oxidative fibers in the soleus muscle than age-matched normoxic-rats. However, there was no difference in the fiber type composition of the soleus muscle between hypoxic- and normoxic-male rats after hypoxic-rats were bred at the sea level atmospheric pressure for 5 weeks. Therefore, it is suggested that a higher percentage of fast-twitch oxidative glycolytic fibers in the muscle is found only under hypoxic conditions and is due to an acute response to hypoxia.
Ishihara
A
A
Laboratory of Neurochemistry, Faculty of Integrated Human Studies, Kyoto University, Japan.
Itho
K
K
Itoh
M
M
Hirofuji
C
C
Hayashi
H
H
D000818:Animals; D001274:Atmospheric Pressure; D001835:Body Weight; D005260:Female; D006651:Histocytochemistry; D000860:Hypoxia / Q000473:pathology*; D008297:Male; D009132:Muscles / Q000737:chemistry* / Q000378:metabolism / Q000473:pathology; D051381:Rats; D017207:Rats, Sprague-Dawley; D012727:Sex Characteristics