Parratt J R, Taggart M J, Wray S
Physiological Laboratory, Liverpool University, UK.
J Reprod Fertil. 1995 Sep;105(1):71-5. doi: 10.1530/jrf.0.1050071.
Changes in intracellular pH have differing effects on contraction in different types of muscle, and between species. Because of the large number of women requiring a caesarean section due to failure to progress in labour, it is important to know how the human myometrium responds to the changes in intracellular pH that may occur during labour. The pH-sensitive dye, carboxy-SNARF, was used to measure intracellular pH in small strips of human myometrium. Intracellular pH and tension were simultaneously recorded in pregnant and nonpregnant tissue. Intracellular pH was altered by the addition of weak acids and bases. Intracellular alkalinization caused an increase in the frequency and amplitude of contractions. Intracellular acidification led to an initial increase in the frequency and/or the amplitude of the contractions, followed by abolition of contractions. Alterations in intracellular pH had profound effects on contraction in human uterine smooth muscle. Possible mechanisms are discussed whereby pH could influence force production, and changes in contraction are related to the speed and extent of the change in intracellular pH.
细胞内pH值的变化对不同类型的肌肉以及不同物种的肌肉收缩有着不同的影响。由于大量女性因产程进展不顺利而需要剖宫产，了解人类子宫肌层如何应对分娩过程中可能发生的细胞内pH值变化非常重要。使用对pH敏感的染料羧基-SNARF来测量人类子宫肌层小条带中的细胞内pH值。在妊娠和非妊娠组织中同时记录细胞内pH值和张力。通过添加弱酸和弱碱来改变细胞内pH值。细胞内碱化导致收缩频率和幅度增加。细胞内酸化导致收缩频率和/或幅度最初增加，随后收缩消失。细胞内pH值的改变对人类子宫平滑肌收缩有深远影响。文中讨论了pH值可能影响力量产生的潜在机制，以及收缩变化与细胞内pH值变化的速度和程度之间的关系。
