Mechanism of Relaxation Via TASK-2 Channels in Uterine Circular Muscle of Mouse
The Korean Journal of Physiology and Pharmacology
;
: 359-365, 2013.
Article
in English
| WPRIM
| ID: wpr-727709
ABSTRACT
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.
Full text:
Available
Index:
WPRIM (Western Pacific)
Main subject:
Plasma
/
Quinidine
/
Relaxation
/
Acidosis
/
Uterine Contraction
/
Uterus
/
4-Aminopyridine
/
Contracts
/
Hydrogen-Ion Concentration
/
Lidocaine
Limits:
Animals
/
Pregnancy
Language:
English
Journal:
The Korean Journal of Physiology and Pharmacology
Year:
2013
Type:
Article
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