Regulation of opiate receptors in mouse brain: arcuate nuclear lesion induces receptor up-regulation and supersensitivity to opiates.
Lesion of the hypothalamic arcuate nucleus of the mouse by neonatal application of monosodium glutamate (MSG) increased the binding of [3H]dihydromorphine to membranes prepared from the midbrain. A saturation curve of [3H]dihydromorphine binding indicated that MSG increased the number of the opiate receptors. The MSG-treated mice also exhibited an enhanced response to morphine and naltrexone regarding thermal pain sensitivity. The physiological implications of opiate receptors up-regulations upon arcuate nuclear lesion are discussed.
D000818:Animals; D001111:Arcuate Nucleus of Hypothalamus / Q000187:drug effects / Q000502:physiology*; D001921:Brain / Q000502:physiology*; D002462:Cell Membrane / Q000378:metabolism; D004090:Dihydromorphine / Q000378:metabolism*; D007700:Kinetics; D008636:Mesencephalon / Q000378:metabolism; D051379:Mice; D008813:Mice, Inbred ICR; D009020:Morphine / Q000494:pharmacology; D009022:Morphine Derivatives / Q000378:metabolism*; D009271:Naltrexone / Q000494:pharmacology; D011957:Receptors, Opioid / Q000187:drug effects / Q000378:metabolism*; D012970:Sodium Glutamate / Q000494:pharmacology
D009022:Morphine Derivatives; D011957:Receptors, Opioid; D009271:Naltrexone; D009020:Morphine; D004090:Dihydromorphine; D012970:Sodium Glutamate