  The $p\bar{\Lambda}$ systems with J=0 and J=1 are dynamically investigated
within the framework of two constituent quark models: the chiral quark model
and the quark delocalization color screening model. The model parameters are
taken from our previous work, which gave a good description of the
proton-antiproton S-wave elastic scattering cross section experimental data.
The $p\bar{\Lambda}$ elastic scattering processes with coupling to
$p\bar{\Sigma}$ state are studied. The results show that, there is no s-wave
bound state as indicated by an enhancement near the threshold of
$p\bar{\Lambda}$ in $J/\psi$ decay. However, a $IJ = {1/2}0$ $p\bar{\Sigma}$
resonance state is given in the quark delocalization color screening model.
