Effects of short-term and long-term androgen treatment on the diaphragm in male and female rats.
Effects of short-term and long-term androgen treatment on the diaphragm in male and female rats.
复制标题
短期和长期雄激素治疗对雄性和雌性大鼠膈肌的影响。
DOI：
10.1152/jappl.1993.75.3.1140
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发表时间：
1993
期刊：
影响因子：
--
通讯作者：
Freeman,K
中科院分区：
文献类型：
--
作者：
Prezant,DJ;Valentine,DE;Gentry,EI;Richner,B;Cahill,J;Freeman,K
在雄性和雌性大鼠中研究了短期（2.5周）和长期（10周）丙酸睾酮（2.5 mg/天; 5天/周）给药对膈肌收缩力、抗疲劳性和纤维类型比例的影响。通过在37 ℃下直接刺激，在体外隔膜肋条制备中测量收缩性和抗疲劳性指数。疲劳模式包括30列车/分钟，5 Hz（50%占空比），10分钟。疲劳抗力指数计算为postfatigue除以基线力。在雌性而非雄性中，睾酮给药导致体重、肋膈重量和收缩力显著增加，抗疲劳指数显著降低。睾酮给药与给药持续时间之间的相互作用显著，短期给药后收缩力（雌性）显著增加，但长期给药后不显著。无论治疗持续时间或实验前雄激素的基础循环水平如何，均未观察到纤维类型比例或面积的显著差异。
The effects of short-term (2.5 wk) and long-term (10 wk) testosterone propionate (2.5 mg/day; 5 days/wk) treatment on diaphragm contractility, fatigue resistance, and fiber type proportions were studied in male and female rats. Contractility and fatigue resistance indexes were measured in an in vitro diaphragm costal strip preparation by direct stimulation at 37 degrees C. The fatigue paradigm consisted of 30 trains/min at 5 Hz (50% duty cycle) for 10 min. Fatigue resistance indexes were calculated as postfatigue divided by baseline forces. In females but not males, testosterone treatment produced significant increases in body weight, costal diaphragm weight, and contractility and significant decreases in fatigue resistance indexes. The interaction between testosterone treatment and the duration of treatment was significant, with the increase in contractility (females) being significant after short-term but not long-term treatment. No significant difference in fiber type proportions or areas was observed, regardless of treatment duration or the preexperimental, basal circulating level of androgen.