Expression profiles of adiponectin receptors in mouse embryos.
Adiponectin is a protein secreted from adipocytes and it plays an important endocrine role in glucose and lipid homeostasis. A reverse correlation between plasma adiponectin concentrations and insulin resistance has been established in both animals and humans. Adiponectin exerts its function by interacting with membrane receptors, including AdipoR1 and AdipoR2. We investigated the expression pattern of these two adiponectin receptors in mouse embryos. At stages E12.5 and E15.5, both AdipoR1 and AdipoR2 are highly expressed in the nervous system including the trigeminal ganglion, glossopharyngeal ganglion and dorsal root ganglia. AdipoR1 is highly expressed in many tissues derived from primitive gut, including the lung, liver, pancreas and small intestines. Generally, the expression level of AdipoR2 is weaker and more restricted than AdipoR1 in most of the tissues. In addition, AdipoR1 expression can be found in heart, vertebrate, developing bones and cartilage, and many other tissues. This study reveals that AdipoR1 and AdipoR2 have differential but overlapping expression profiles during mouse development.