title: The sensitivity to noxious heat in relation to brain and liver opioid glucuronidation in inbred strains of mice.
abstract: The glucuronidation of morphine and naloxone was demonstrated in the brain and liver in 2 inbred strains of mice, C57BL/6J (B6) and DBA/2J (D2) and their F1 hybrid generation. These strains showed a significant difference in latency of withdrawal in the tail-immersion test, the B6 strain being the most sensitive. The rate of naloxone glucuronidation in the brain was 5 times higher in the B6 than in the D2 strain. In the liver the UDP-glucuronosyl transferase (UDPGT) activity was slightly higher in the D2 strain. The naloxone- and morphine-3'-glucuronide (N3G, M3G) formation rate ratio was close to 1 in both the brain and liver in all except the B6 strain, where it was 2.6 in the brain. There was a correlation between formation rate of M3G and N3G (r = 0.65 brain and r = 0.73 liver). Our results indicate a common glucuronidation pathway for morphine and naloxone.
authors.affiliation: Division of Clinical Pharmacology, University Hospital, UppsalaSweden Department of Medical and Physiological Chemistry, Biomedical Center, UppsalaSweden.
authors.forename: Agneta
authors.initials: A
authors.lastname: Wahlström
authors.forename: Lars-Gustav
authors.initials: LG
authors.lastname: Lundin
authors.forename: Birgitta
authors.initials: B
authors.lastname: Ask
authors.forename: Anders
authors.initials: A
authors.lastname: Rane
mesh_terms: D000818:Animals; D001921:Brain / Q000201:enzymology*; D014453:Glucuronosyltransferase / Q000378:metabolism*; D006358:Hot Temperature; D008099:Liver / Q000201:enzymology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D009020:Morphine / Q000378:metabolism*; D009270:Naloxone / Q000378:metabolism*; D010146:Pain / Q000378:metabolism*; D013045:Species Specificity
chemical_list: D009270:Naloxone; D009020:Morphine; D014453:Glucuronosyltransferase