Effect of steroids on diaphragm of newborn, weanling adolescent, and adult rats.
Effect of steroids on diaphragm of newborn, weanling adolescent, and adult rats.
复制标题
类固醇对新生、断奶青少年和成年大鼠膈肌的影响。
DOI：
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发表时间：
1992
期刊：
影响因子：
--
通讯作者：
M. Aubier
中科院分区：
文献类型：
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作者：
T. T. Trang;N. Viires;M. Aubier
本研究的目的是比较地塞米松对大鼠出生后和成年后膈肌的影响。每组48只新生大鼠、60只断奶青少年大鼠和60只成年大鼠（1）接受DXM治疗（ST，类固醇治疗动物）或（2）未治疗和成对喂养（C，对照动物）。出生后，24只新生大鼠与其母亲一起饲养，每天肌肉注射地塞米松0.5mg/kg体重，共2 wk。30只断乳青少年和30只成年大鼠用地塞米松1 mg/kg/天肌肉注射治疗2周。在ST动物和年龄匹配的C动物之间比较隔膜性能。获得了身体、膈肌、趾长伸肌（EDL）和比目鱼肌的重量。在体外制备中研究隔膜条以评估收缩和耐力特性。与年龄匹配的C组动物相比，所有ST组动物的体重和总膈肌重量均降低（p <0.001）。与成年动物相比，在新生和断奶的青少年ST动物中，膈肌重量的损失略小于肢体肌肉（p <0.05）。然而，成年和断奶青少年ST动物的横膈膜显示出不受影响的抽搐特征，标准化的力-频率曲线和耐力。同时，在新生ST动物中，膈肌萎缩与纤维横截面积和肌肉重量标准化的力显著降低（p <0.01）和耐力降低（p <0.05）相关。我们的结论是，DXM对膈肌的影响取决于肌肉的发育状态，在给药的时候。
The purpose of this study was to compare the effects of dexamethasone on the rat diaphragm during the postnatal period and into adulthood. Groups of 48 newborn, 60 weanling adolescent, and 60 adult rats were either (1) treated with DXM (ST, steroid-treated animals) or (2) untreated and pair-fed (C, control animals). After birth, 24 newborn rats were kept with their mother, which received a daily intramuscular injection of 0.5 mg/kg body weight of dexamethasone for 2 wk. Groups of thirty weanling adolescent and 30 adult rats were treated with 1 mg/kg/day of dexamethasone given intramuscularly for 2 wk. Diaphragm performance was compared between ST animals and age-matched C animals. Weights of the body, the diaphragm, the extensor digitorum longus (EDL), and the soleus were obtained. Diaphragm strips were studied in an in vitro preparation to assess contractile and endurance properties. In all the ST animals, body and total diaphragm weights were reduced compared with age-matched C animals (p less than 0.001). In newborn and weanling adolescent ST animals, loss in diaphragm weight was slightly less than in limb muscles, in contrast to adult animals (p less than 0.05). However, diaphragms from adult and weanling adolescent ST animals showed unaffected twitch characteristics, normalized force-frequency curves, and endurance capacity. In the meantime, in newborn ST animals, diaphragm atrophy was associated with significantly decreased force normalized for fiber cross-sectional area and muscle weight (p less than 0.01) and decreased endurance capacity (p less than 0.05). We conclude that the effects of DXM on the diaphragm depend on the developmental status of the muscle at the time of drug administration.
新生大鼠趾长伸肌、膈肌和比目鱼肌中的肌球蛋白亚型。
DOI：
10.1152/ajplung.1990.259.2.l116
发表时间：
1990
期刊：
The American journal of physiology
影响因子：
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作者：
LaFramboise,WA;Daood,MJ;Guthrie,RD;Butler-Browne,GS;Whalen,RG;Ontell,M
通讯作者：
Ontell,M