Apoptotic endometrial caspase-3 mediated phospholipase a2 activation, a critical component in programing uterine receptivity

Our analysis determined that apoptotic caspase-3 and iPLA2 activation were limited to the endometrial compartments of the control and unilateral uteri on 1dpc and were not found in the bilateral ligated uterine horn on 3 or 6 dpc. Our data indicates that the presence of a conceptus on 1 dpc triggers an increase in endometrial apoptotic caspase-3 mediated iPLA2 activation. iPLA2 when activated causes the hydrolysis of fatty acids resulting in arachidonic acid release and production of PGE2, which in early pregnancy has been demonstrated to act in a leutoprotective manner, prolonging progesterone synthesis and promoting uterine receptivity.