Differentiation of XXXX cells to a neural or cardiomyocyte lineage is associated with selective expression of endothelin receptors.

@entity1184 @entity1627 @entity189 @entity3733 @entity1968 @entity2231 @entity4452
Endothelins (ETs) were initially characterized as potent vasoactive peptides acting through at least two distinct receptors, @entity2231 and @entity1627 . Subsequently, their significant growth- and @entity1184 -promoting properties in cardiac and other cells were recognized. We investigated the expression of endothelin receptors during differentiation of a pluripotential @entity189 cell line ( @entity4452 ) to a cardiomyocyte or a neural lineage. These cells resemble those of the inner cell mass of the blastocyst, and their differentiation is believed to closely mimic critical events in early embryogenesis. Differentiation of @entity4452 to a cardiomyocyte lineage, by aggregation and exposure to @entity3733 resulted in induction of @entity2231 receptors as demonstrated by radioligand binding studies, Northern blotting, and reporter gene analysis. Moreover, the @entity4452 differentiated to a cardiac lineage responded to ET-1 with a 3-fold increase in the secretion of atrial natriuretic peptide. In contrast, differentiation to a neural lineage, by aggregation and exposure to @entity1968 , was associated with the induction of predominantly @entity1627 . Therefore, selective differentiation of the @entity4452 led to the differential expression of endothelin receptors in a pattern consistent with that observed in normal myocardial and neural tissue. The induction of endothelin receptors in a model system of early embryogenesis provides strong support for the critical role of this peptide/receptor family in differentiation and development. As well, this model system is well suited for the study of the mechanisms controlling endothelin receptor expression during differentiation.
