A comparison of microwave irradiation and decapitation. Basal levels of dynorphin and enkephalin peptides and the effect of morphine treatment on dynorphin peptides
1997 (English)In: Neuropeptides, ISSN 0143-4179, E-ISSN 1532-2785, Vol. 31, no 4, 357-365 p.Article in journal (Refereed) Published
Opioid peptides were analysed in tissue extracts of various brain structures and the pituitary gland from rats sacrificed by microwave irradiation, and compared with peptide levels in tissue extracts from decapitated rats. Dynorphin A, dynorphin B and Leu-enkephalinArg6, derived from prodynorphin, and Met-enkephalinArg6Phe7 from proenkephalin, were measured. Basal immunoreactive levels of dynorphin A and B were consistently higher in extracts from microwave-irradiated rats, whereas in these extracts immunoreactive levels of Leu-enkephalinArg6, an endogenous metabolite of dynorphin peptides, were either lower than, the same as or higher than in decapitated rats. Immunoreactive levels of Met-enkephalinArg6Phe7 were higher in microwave-irradiated rats. Effects of morphine treatment on prodynorphin peptide levels were evaluated and compared with previous findings in decapitated rats. Dynorphin immunoreactive levels were higher in the nucleus accumbens and striatum of morphine-tolerant rats than in corresponding areas in saline-treated rats. These results indicate tissue-specific metabolism of prodynorphin peptides and show that metabolism of opioid peptides occurs during the dissection procedure after decapitation of the rat even though precautions are taken to minimize degradation.
Place, publisher, year, edition, pages
1997. Vol. 31, no 4, 357-365 p.
Medical and Health Sciences Pharmaceutical Sciences
IdentifiersURN: urn:nbn:se:uu:diva-50728DOI: 10.1016/S0143-4179(97)90072-XISI: A1997XX36700011PubMedID: 9308024OAI: oai:DiVA.org:uu-50728DiVA: diva2:78637