Effect of undernutrition on contractile and fatigue properties of rat diaphragm during development.
Effect of undernutrition on contractile and fatigue properties of rat diaphragm during development.
复制标题
营养不良对发育过程中大鼠膈肌收缩和疲劳特性的影响。
DOI：
10.1152/jappl.1993.74.5.2121
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发表时间：
1993
期刊：
影响因子：
--
通讯作者：
Guthrie,RD
中科院分区：
文献类型：
--
作者：
Brozanski,BS;Watchko,JF;O'Day,TL;Guthrie,RD
The present study was designed to assess the effects of combined pre- and postnatal undernutrition on the in vitro contractile and fatigue properties of the rat diaphragm during development. In vitro direct stimulation of costal diaphragm from control (CTL) and undernourished (UN) rats was done on postnatal days 1, 4, 14, 21, 30, 40, 50, and 60. Combined pre- and postnatal undernutrition resulted in stunted animal growth but did not alter the diaphragm-to-total body weight ratio. Twitch contraction time, half-relaxation time, and force-frequency relationships were not consistently affected by undernutrition. Specific twitch force and specific tetanic force were also unchanged in the UN group. Fatigue resistance was high and comparable in UN and CTL groups at days 1 and 4. At day 14 and thereafter, fatigue resistance declined but was consistently higher in the UN than in the CTL group. We conclude that combined pre- and postnatal undernutrition results in a significant increase in fatigue resistance of the diaphragm compared with CTL, whereas diaphragm muscle contractile properties are not appreciably affected by prolonged undernutrition.
