Uterus SERCA

Ca2+ entry, Ca2+-uptake into the SR by SERCA, Ca2+ extrusion from the cell and dephosphorylation of the myosin light chains. The t ype 1 phosphatase, myosin light chain phosphatase (MLCP) dephosphorylates myosin. As with MLCK its activity is physiologically regulated, e.g. its activity is decreased following phosphorylation via Rho associated kinase (Somlyo Somlyo 2000). In the uterus we have found a small but significant reduction of force, but not Ca2+ when Rho-associated kinase is inhibited (Kupittayanant et al 2001b). 

In the uterus the SR is a pronounced and complex organelle, which appears to be under some degree of hormonal control. For example, its size, SERCA expression and release mechanisms show alteration with pregnancy. As yet there has been little study of the molecular and mechanistic processes that lead to these changes in the... 

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