INS and obesity due to melanocortin 4 receptor deficiency: The effects of RXR-specific ligands on glucose, insulinresistance, and obesity are summarized in Table 2.Review of the literature describing the antidiabetic effects ofrexinoids shows that RXR-selective ligands do not mediate theirglucose-lowering and insulin-sensitizing effects by merely“mimicking” the effects of TZDs.Initially thought to synergize the actions of TZDsthrough binding to the RXR component of the RXR:PPARγheterodimer, recent evidence clearly demonstrates that these twoclasses of compounds mediate their actions via distinctmechanisms.