PGT and apoptosis

A method for screening an apoptosis inhibitor characterized by screening a candidate via an effect on PGT. A cell protecting agent containing as the active ingredient a substance which can be incorporated into cells via prostaglandin transporter (PGT); and a screening method therefor comprising measuring the uptake into cells via PGT. An apoptosis inducer containing as the active ingredient a substance having a PGT inhibitory effect; and a screening method therefor comprising measuring the ability to induce apoptosis of cells with the expression of PGT. Because of having a cell apoptosis inhibitory effect, the cell protecting agent is useful as a nerve cell apoptosis inhibitor, a nerve cell protecting agent, etc. and applicable to the prevention or treatment of nervous diseases, etc. The apoptosis inducer is useful in preventing and/or treating diseases in association with cell proliferation such as tumor, etc.