Send to

Choose Destination
See comment in PubMed Commons below
Korean J Physiol Pharmacol. 2013 Aug;17(4):359-65. doi: 10.4196/kjpp.2013.17.4.359. Epub 2013 Jul 30.

Mechanism of Relaxation Via TASK-2 Channels in Uterine Circular Muscle of Mouse.

Author information

  • 1Department of Obstetrics and Gynecology, Chungbuk National University College of Medicine, Cheongju 361-763, Korea.


Plasma pH can be altered during pregnancy and at labor. Membrane excitability of smooth muscle including uterine muscle is suppressed by the activation of K(+) channels. Because contractility of uterine muscle is regulated by extracellular pH and humoral factors, K(+) conductance could be connected to factors regulating uterine contractility during pregnancy. Here, we showed that TASK-2 inhibitors such as quinidine, lidocaine, and extracellular acidosis produced contraction in uterine circular muscle of mouse. Furthermore, contractility was significantly increased in pregnant uterine circular muscle than that of non-pregnant muscle. These patterns were not changed even in the presence of tetraetylammonium (TEA) and 4-aminopyridine (4-AP). Finally, TASK-2 inhibitors induced strong myometrial contraction even in the presence of L-methionine, a known inhibitor of stretchactivated channels in myometrium. When compared to non-pregnant myometrium, pregnant myometrium showed increased immunohistochemical expression of TASK-2. Therefore, TASK-2, seems to play a key role during regulation of myometrial contractility in the pregnancy and provides new insight into preventing preterm delivery.


Relaxation; TASK-2; Uterus

PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for The Korean Physiological Society and The Korean Society of Pharmacology Icon for PubMed Central
    Loading ...
    Write to the Help Desk