title: Magnesium ions and opioid agonist activity in streptozotocin-induced hyperalgesia.
abstract: Streptozotocin-induced hyperglycemia accompanied by a chronic decrease in the nociceptive threshold is considered a useful model of experimental hyperalgesia. We examined (1) the effect of the opioid receptor agonists and (2) the effect of the magnesium ions (Mg(2+)) on the antinociceptive action of opioid agonists in a diabetic neuropathic pain model. When administered alone, opioid agonists like morphine (5 mg/kg i.p.) and fentanyl (0.0625 mg/kg i.p.), as well as the partial agonist buprenorphine (0.075 mg/kg) had only little effect on streptozotocin-induced hyperalgesia. However, pretreatment with Mg(2+) at a dose of 40 mg magnesium sulfate/kg i.p. markedly enhanced the analgesic activity of all three investigated opioids. Practical aspects of co-administration of magnesium and opioids in diabetic neuropathy are discussed.
authors.affiliation: Department of Pharmacodynamics, Medical University of Warsaw, Warsaw, Poland. mbujalska@gmail.com
authors.forename: Magdalena
authors.initials: M
authors.lastname: Bujalska
authors.forename: Ewelina
authors.initials: E
authors.lastname: Malinowska
authors.forename: Helena
authors.initials: H
authors.lastname: Makulska-Nowak
authors.forename: Stanisław Witold
authors.initials: SW
authors.lastname: Gumułka
mesh_terms: D000701:Analgesics, Opioid / Q000494:pharmacology*; D000818:Animals; D002047:Buprenorphine / Q000494:pharmacology; D003921:Diabetes Mellitus, Experimental / Q000150:complications; D003929:Diabetic Neuropathies / Q000188:drug therapy* / Q000503:physiopathology; D004357:Drug Synergism; D004359:Drug Therapy, Combination; D005283:Fentanyl / Q000494:pharmacology; D006930:Hyperalgesia / Q000188:drug therapy* / Q000209:etiology; D007274:Injections, Intraperitoneal; D008278:Magnesium Sulfate / Q000494:pharmacology*; D008297:Male; D009020:Morphine / Q000494:pharmacology; D010147:Pain Measurement; D017288:Pain Threshold / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D013311:Streptozocin
chemical_list: D000701:Analgesics, Opioid; D002047:Buprenorphine; D013311:Streptozocin; D008278:Magnesium Sulfate; D009020:Morphine; D005283:Fentanyl