粘着斑激酶的激活参与了收缩刺激诱导的小鼠膀胱逼尿肌收缩。

Focal adhesion kinase activation is involved in contractile stimulation-induced detrusor muscle contraction in mice.

机构信息

Department of Surgery, MetroHealth Medical Center, Case Western Reserve University, Cleveland, OH, USA; Department of Chemistry, Cleveland State University, Cleveland, OH, USA.

Department of Chemistry, Cleveland State University, Cleveland, OH, USA; Department of Inflammation & Immunity, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA.

出版信息

Eur J Pharmacol. 2023 Aug 5;952:175807. doi: 10.1016/j.ejphar.2023.175807. Epub 2023 May 24.

DOI:10.1016/j.ejphar.2023.175807

PMID:37236435

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC10330804/

Abstract

Recent studies suggested smooth muscle contraction may involve mechanisms besides the myosin regulatory light chain (MLC) phosphorylation-induced actomyosin crossbridge cycling. This study aims to determine if focal adhesion kinase (FAK) activation is involved in mouse detrusor muscle contraction. The mouse detrusor muscle strips were preincubated with PF-573228 (2 μM), latrunculin B (1 μM), or the same volume of vehicle (DMSO) for 30 min. The contractile responses to KCl (90 mM), electrical field stimulation (EFS, 2-32 Hz), or carbachol (CCh, 10-10 M) were measured. In a separate experiment, the phosphorylated FAK (p-FAK) and MLC (p-MLC) levels were measured in the detrusor strips stimulated with CCh (10 μM) after incubation with PF-573228 or vehicle (DMSO) compared to those with vehicle incubation but without CCh stimulation. KCl-induced contractile responses decreased significantly after incubation with PF-573228 or latrunculin B compared to the corresponding vehicle-treated strips (p < 0.0001). The contractile responses induced by EFS were markedly inhibited by preincubation with PF-573228 at 8, 16, and 32 Hz (p < 0.05) or latrunculin B at 16 and 32 Hz (p < 0.01). Following the application of PF-573228 or Latrunculin B, CCh-induced dose-response contractions were lower than the corresponding vehicle group (p = 0.0021 and 0.0003, respectively). Western blot examination showed that CCh stimulation enhanced the expression of p-FAK and p-MLC, while preincubation with PF-573228 prevented the increase of p-FAK but not p-MLC. In conclusion, FAK activation involves tension development induced by contractile stimulation in the mouse detrusor muscle. This effect is likely caused by promoting actin polymerization rather than elevating MLC phosphorylation.

摘要

最近的研究表明，平滑肌收缩可能涉及除肌球蛋白调节轻链（MLC）磷酸化诱导的肌动球蛋白交联循环之外的机制。本研究旨在确定粘着斑激酶（FAK）的激活是否参与了小鼠逼尿肌收缩。将小鼠逼尿肌条用 PF-573228（2 μM）、Latrunculin B（1 μM）或相同体积的载体（DMSO）预孵育 30 min。测量 KCl（90 mM）、电刺激（EFS，2-32 Hz）或卡巴胆碱（CCh，10-10 M）引起的收缩反应。在另一个实验中，在与 PF-573228 或载体（DMSO）孵育后，用 CCh（10 μM）刺激逼尿肌条，测量磷酸化 FAK（p-FAK）和肌球蛋白轻链（p-MLC）的水平，与用载体孵育但无 CCh 刺激的逼尿肌条进行比较。与相应的载体处理条相比，用 PF-573228 或 Latrunculin B 孵育后，KCl 诱导的收缩反应明显降低（p<0.0001）。用 PF-573228 在 8、16 和 32 Hz 或 Latrunculin B 在 16 和 32 Hz 预孵育显著抑制 EFS 诱导的收缩反应（p<0.05 或 p<0.01）。应用 PF-573228 或 Latrunculin B 后，CCh 诱导的剂量反应收缩低于相应的载体组（p=0.0021 和 0.0003）。Western blot 检查显示，CCh 刺激增强了 p-FAK 和 p-MLC 的表达，而 PF-573228 预孵育阻止了 p-FAK 的增加，但不阻止 p-MLC 的增加。总之，FAK 的激活涉及到小鼠逼尿肌收缩刺激引起的张力发展。这种作用可能是通过促进肌动蛋白聚合而不是增加 MLC 磷酸化来实现的。