The studies presented herein describe the usefulness of glycerol in enhancing the binding activity and stability of detergent-solubilized gonadotropin (LH/hCG) receptors. The data presented show that when Leydig tumor cells (designated MA-10) are extracted with Triton X-100 in the presence of glycerol, one can quantitatively solubilize the cellular LH/hCG receptors without losing hormone-binding activity. It is also shown that in the presence of glycerol, the free soluble receptors can be maintained for at least 3 days with little or no reduction in their hormone-binding activity. These findings should prove useful for future studies on the structure and properties of gonadotropin receptors.