Length-tension relationship of mammalian diaphragm muscles.
Length-tension relationship of mammalian diaphragm muscles.
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哺乳动物膈肌的长度-张力关系。
DOI：
10.1152/jappl.1983.54.6.1681
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发表时间：
1983
期刊：
影响因子：
--
通讯作者：
Faulkner,JA
中科院分区：
文献类型：
--
作者：
McCully,KK;Faulkner,JA
我们验证了横隔肌的长度-张力关系不同于其他骨骼肌的假设。在37℃下对大鼠、猫、恒河猴、狗和猪的小束横隔肌的等长收缩特性进行了体外测量。对于所有物种的横隔肌，抽搐收缩和松弛时间和肌原纤维ATPase组织化学显示为快肌纤维和慢肌纤维的混合体。在400ms的强直刺激下，在肌纤维长度的50%到130%之间的肌纤维长度的最大活动张力(LO)处记录到等长张力。当长度低于LO的60%-70%时，强直性张力在400ms内没有达到平台期。随着刺激时间的延长，主动张力可记录到LO的30%~40%。来自横隔肌的纤维束的长度-张力曲线在不同物种之间没有差异，并且与报道的完整肢体肌肉的结果一致。
We tested the hypothesis that the length-tension relationship of diaphragm muscle is different from that of other skeletal muscle. Isometric contractile properties of small bundles of diaphragm muscle from rats, cats, rhesus monkeys, dogs, and pigs were measured in vitro at 37 degrees C. For diaphragm muscles from all species, twitch contraction and relaxation times and histochemical myofibrillar ATPase indicated a mixture of fast and slow muscle fiber types. By use of tetanic stimulations of 400-ms duration, isometric tension was recorded from bundles of diaphragm muscle at lengths between 50 and 130% of the muscle fiber length at which active tension was maximal (Lo). At lengths below 60–70% of Lo, tetanic tension did not reach a plateau within 400 ms. With longer stimulation durations, active tension could be recorded between 30 and 40% of Lo. The length-tension curves for bundles of fibers from the diaphragm muscle were not different among species and were consistent with results reported for intact limb muscles.