Melatonin enhances leptin expression by rat adipocytes in the presence of insulin.

  title={Melatonin enhances leptin expression by rat adipocytes in the presence of insulin.},
  author={Maria Isabel Cardoso Alonso-Vale and Sandra Andreotti and Sidney Barnab{\'e} Peres and Gabriel Forato Anh{\^e} and Cristina das Neves Borges-Silva and Jos{\'e} Cipolla Neto and Fabio Bessa Lima},
  journal={American journal of physiology. Endocrinology and metabolism},
  volume={288 4},
Leptin and melatonin play an important role in the regulation of body mass and energy balance. Both hormones show a circadian rhythm, with increasing values at night. In addition, melatonin receptors were recently described in adipocytes, where leptin is synthesized. Here, we investigated the influence of melatonin and its interaction with insulin and dexamethasone on leptin expression. Isolated rat adipocytes were incubated with melatonin (1 nM) alone or in combination with insulin (5 nM) and… 

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