XXXX mobilizes calcium from a unique heparin-sensitive and @entity2426 -sensitive store in single myometrial cells from pregnant @entity35 .

@entity398 @entity671 @entity2426 @entity35 @entity3281 @entity8452 @entity5834 @entity58766 @entity593 @entity141 @entity54568 @entity934
Intracellular free @entity141 concentration ([ @entity141 ]i) was monitored using the fluorescence from the dye @entity593 -AM in single myometrial cells from pregnant @entity35 . @entity398 and @entity934 applied to the cell evoked an initial peak in [ @entity141 ]i followed by a smaller sustained rise which was rapidly terminated upon removal of @entity934 or persisted after @entity398 removal. A @entity141 channel blocker ( @entity58766 ) and external @entity141 removal decreased both the transient and sustained rises in [ @entity141 ]i suggesting that @entity141 influx through L-type @entity141 channels participated in the global @entity141 response induced by @entity398 . However, the initial peak in [ @entity141 ]i produced by @entity398 was mainly due to @entity141 store release: it was abolished by inclusion of heparin [which blocks @entity671 (InsP3) receptors] in the pipette (whole-cell recording mode of patch-clamp) and external application of @entity2426 (which blocks sarcoplasmic reticulum @entity141 -ATPases). In contrast, the transient @entity141 response induced by @entity398 was unaffected by @entity8452 . Moreover, @entity5834 failed to induce a rise in [ @entity141 ]i but reduced the @entity398 -induced transient @entity141 response. The later sustained rise in [ @entity141 ]i produced by @entity398 was due to the entry of @entity141 into the cell as it was suppressed in external @entity141 -free solution. The @entity141 entry pathway is permeable to @entity3281 ions, in contrast to that described in various vascular and visceral smooth muscle cells. @entity398 -induced @entity141 release is blocked by the @entity398 antagonist @entity54568 . The prolonged increase in [ @entity141 ]i after @entity398 removal is rapidly terminated by addition of the @entity398 antagonist suggesting that @entity398 dissociation from its receptor is very slow.(ABSTRACT TRUNCATED AT 250 WORDS)
