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Hormonal influence on ionic channels in myometrium
1Department of Obstetrics and Gynecology, University of Pennsylvania Medical Center, Philadelphia 19104.
Abstract:
Smooth muscle cells in culture isolated from myometrium were characterized by scanning microscope and immunohistochemistry. Using the whole-cell patch-clamp configuration, and the single channel bilayer technique, the properties of ionic channels expressed in both non-pregnant and pregnant myometrium have been described. The predominantly expressed potassium channel changes from a transient inactivating outward current seen before puberty, to a calcium sensitive delayed outward current present in the adult stage. A change in the calcium channel population occurs from the nonpregnant to the pregnant state. Finally, sodium channels are expressed with greater frequency towards the end of gestation suggesting that these channels may play a role in labor.
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