Open AccessImmunolocalization and expression of small‐conductance calcium‐activated potassium channels in human myometrium
Author(s) -
Rosenbaum Sofia T.,
Svalø Julie,
Nielsen Karsten,
Larsen Torben,
Jørgensen Jørgen C.,
Bouchelouche Pierre
Publication year - 2012
Publication title -
journal of cellular and molecular medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.44
H-Index - 130
eISSN - 1582-4934
pISSN - 1582-1838
DOI - 10.1111/j.1582-4934.2012.01627.x
Subject(s) - myometrium , immunohistochemistry , potassium channel , contractility , medicine , endocrinology , calcium activated potassium channel , andrology , biology , chemistry , uterus
Small‐conductance calcium‐activated potassium ( SK 3) channels have been detected in human myometrium and we have previously shown a functional role of SK channels in human myometrium in vitro . The aims of this study were to identify the precise localization of SK 3 channels and to quantify SK 3 m RNA expression in myometrium from pregnant and non‐pregnant women. Myometrial biopsies were obtained from pregnant ( n = 11) and non‐pregnant ( n = 11) women. The expression of SK 3 channels was assessed using immunohistochemistry and SK 3 m RNA was determined by q RT ‐ PCR . In non‐pregnant myometrium SK 3 immunoreactivity was observed in CD 34 positive ( CD 34 + ) interstitial Cajal‐like cells ( ICLC ), now called telocytes. Although CD 34 + cells were also present in pregnant myometrium, they lacked SK 3 immunoreactivity. Furthermore, the immunohistochemical results showed that SK 3 expression in vascular endothelium was similar between the two groups. CD 117 immunoreactivity was only detected in small round cells that resemble mast cells. Compared to non‐pregnant myometrium we found significantly less SK 3 m RNA in pregnant myometrium. We demonstrate that SK 3 channels are localized solely in CD 34 + cells and not in smooth muscle cells, and that the molecular expression of SK 3 channels is higher in non‐pregnant compared to pregnant myometrium. On the basis of our previous study and the present findings, we propose that SK 3 activators reduce contractility in human myometrium by modulating telocyte function. This is the first report to provide evidence for a possible role of SK 3 channels in human uterine telocytes.