Mix and Match: Heterodimers and Opioid Tolerance

Department of Neurology and Molecular Pharmacology & Chemistry Program, Memorial Sloan-Kettering Cancer Center, New York, NY 10065.
Neuron (Impact Factor: 15.05). 01/2011; 69(1):6-8. DOI: 10.1016/j.neuron.2010.12.030
Source: PubMed


Heterodimerization of G-protein coupled receptors has become increasingly recognized as a valuable mechanism to increase receptor diversity. Heterodimers have been observed in the opioid receptor family, but one of the most intriguing is that formed between mu and delta opioid receptors. In this issue of Neuron He et al. present evidence further implicating these heterodimers in morphine tolerance.

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Available from: Ying-Xian Pan, Mar 26, 2014
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    • "As espoused by most investigators, opioid tolerance is believed to be caused by ligand-receptor inefficiency [44]. Evidence suggests that endocytosis, downregulation of receptors, upregulation of P-glycoprotein, and mu/delta heterodimer formation may be causes of tolerance [45–47]. The hypotheses presented in this paper, regardless of how elegant they may appear, could be inaccurate. "
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