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opioid receptor
opioid receptor An opioid receptor is a protein on a cell’s surface that attaches to opioids and starts internal cell changes that affect how the cell behaves.
An opioid receptor is a protein on a cell’s surface that attaches to opioids and starts internal cell changes that affect how the cell behaves. In mammals, natural substances that act on these receptors include enkephalins, endorphins, and dynorphins, and the main receptor classes are mu, delta, and kappa.