Zakharov S I, Bogdanov K Iu, Rozenshtraukh L V
Biull Eksp Biol Med. 1984 Jun;97(6):643-5.
The existence of mechanical noise (MN) has been demonstrated in isolated papillary muscles of rats at rest. The mean amplitude of the MN was about 1 mg, the mean frequency 1.5 Hz (t 22 degrees C). A good agreement was found between the MN amplitude and the contracture level of the muscle. However, during long contractures, the correlation between the noise and contracture magnitude was disturbed. There was no relationship between the MN amplitude and contracture magnitude during exposures inducing metabolic alterations (hypoxia, NaCN) and upsetting the work of the sarcoplasmic reticulum (caffeine). It is believed that the MN amplitude is in a good agreement with the contracture magnitude and, therefore, with the concentration of intracellular Ca2+, if the sarcoplasmic reticulum and contractile elements of the cells are intact.
在静息状态下的大鼠离体乳头肌中已证实存在机械噪声（MN）。MN的平均振幅约为1毫克，平均频率为1.5赫兹（温度22摄氏度）。发现MN振幅与肌肉挛缩程度之间有良好的一致性。然而，在长时间挛缩过程中，噪声与挛缩幅度之间的相关性受到干扰。在诱导代谢改变（缺氧、氰化钠）和扰乱肌浆网功能（咖啡因）的暴露过程中，MN振幅与挛缩幅度之间没有关系。据信，如果细胞的肌浆网和收缩元件完整，MN振幅与挛缩幅度以及细胞内Ca2+浓度有良好的一致性。
