MORPHOLOGICAL AND ELECTRICAL PROPERTIES OF HUMAN TROPHOBLAST CHORIOCARCINOMA, BEWO CELLS

MR CANTERO, AJ RAMOS, P ZHANG, MK RAYCHOWDHURY, A GREEN, D MACPHEE, AND CANTIELLO HF

Los Cocos, Córdoba

Congreso; III Latin American Symposium on Maternal-Fetal Interaction and Placenta: Basic & Clinical Research; 2007

The syncytiotrophoblast of the placenta arises from fusion of stem cells called cytotrophoblasts. The early mechanisms associated with the cAMP-induced cell fusion and syncytialization of these cells is still unknown. In the present study, we used the whole-cell and single channel patch clamping techniques to assess the electrical properties of BeWo cells under quiescent conditions and after cAMP stimulation. A pleiotropic array of electrical phenotypes was observed suggesting that some BeWo cells displayed electrical activity consistent with the presence of voltage-activated cation channels. Most BeWo cells had, however, a low, slightly outwardly rectifying basal whole cell conductance. Acute addition of a cAMP cocktail increased the whole cell conductance. The correlation between the whole cell conductance and its reversal potential suggest that cAMP elicits both, a decrease in the voltage-gated conductance, and an increase in a ??leak?? pathway consistent with the activation of non-selective cation channels, but not with a major change in morphological features. Several cation channel proteins associated with epithelial ion transport, including aENaC and polycystin-2, expressed in human term syncytiotrophoblast, were immunocytochemically observed, but found non-functional in the quiescent BeWo cells. These data suggest the presence and regulation of cation channel activity associated with both salt and signaling in cytotrophoblastic cells prior to syncytialization.