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There is a strong argument in favor of the shapes of planetary nebulae(PNe)being related to angular momentum of the central engine.It has also been found that the PN inclinations are closely related to the orbital inclinations of the close-binary central stars.Therefore,bipolar PNe as test particles can be used to determine relativistic frame-dragging effects induced by the rotating supermassive black hole(SMBH)located at the Galactic center.In the present study,we have used the Wide Field Spectrograph(WiFeS)to perform the optical integral field unit(IFU)spectroscopy of a sample of the Galactic bulge planetary nebulae with Wolf-Rayet and weak emission-line central stars.The spatially resolved velocity distributions of the Hα emission line were used to determine the kinematic structure and orientation of PNe in our sample.Comparing the velocity maps provided by our IFU observations with those produced by kinematic models allowed us to deconvolve the projection effect from the nebulas inherent shape and determine the orientations of their symmetric axes onto the plane of the sky.It is found that the Galactic position angles(GPA)of the symmetry axes of a few PNe with Galactic longitudes between 352 and 8 degree are roughly around 80–100 degree,where the GPA is the position angle projected onto the sky plane,measured from the North Galactic Pole towards the Galactic east.Our results indicate that the major axes of these PNe are roughly aligned with the Galactic plane.We believe that further observations of a larger sample of bipolar PNe near the Galactic center will help to understand the physics of the rotating SMBH and the Galactic bulge.