An opioid pancreatic peptide produces ileal muscle inhibition and naloxone-reversible analgesia.
The opioid activity of immunoreactive beta-endorphin-like peptide extracted from pork pancreas duplicates the effects of morphine and synthetic beta-endorphin when measured by inhibition of isolated guinea pig ileal muscle response to electro-stimulation in vitro and by morphine-like analgesia following intravenous injection in the mouse. These responses are reversed by the opiate antagonist naloxone, indicating that a potent opioid mu receptor binding ligand is present in pancreatic extract. These findings imply a pancreatic source of plasma immunoreactive beta-endorphin that may explain a number of physiological and behavioral effects generally attributed to hypophyseal beta-endorphin alone.
Kimball
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Virginia Mason Research Center, Seattle, WA 98101.
Iqbal
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Huang
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Sutton
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D000700:Analgesics; D000818:Animals; D006168:Guinea Pigs; D007082:Ileum / Q000187:drug effects; D066298:In Vitro Techniques; D051379:Mice; D009119:Muscle Contraction / Q000187:drug effects*; D009270:Naloxone / Q000494:pharmacology; D010147:Pain Measurement; D010187:Pancreatic Hormones / Q000302:isolation & purification / Q000378:metabolism; D011957:Receptors, Opioid / Q000378:metabolism; D001615:beta-Endorphin / Q000302:isolation & purification / Q000378:metabolism
D000700:Analgesics; D010187:Pancreatic Hormones; D011957:Receptors, Opioid; D009270:Naloxone; D001615:beta-Endorphin