To analyse opioid peptides in tissue extracts of various brain structures and the pituitary gland from rats sacrificed by microwave irradiation, and to compare with peptide levels from decapitated rats.
Exposure duration: 2 s
Levels of dynorphin A and B were consistently higher in extracts from microwave-exposed rats, whereas in these extracts immunoreactive levels of Leu-enkephalin Arg6, an endogenous metabolite of dynorphin peptides, were either lower than, the same as or higher than in decapitated animals. Immunoreactive levels of Met-enkephalin Arg6Phe7 were higher in microwave-exposed animals.
Dynorphin immunoreactive levels were higher in the nucleus accumbens and striatum of morphine-tolerant animals than in corresponding areas in saline-treated rats.
These findings indicate tissue-specific metabolism of prodynorphin peptides. They show that metabolism of opioid peptides occurs during the dissection procedure after decapitation of the rat even though precautions were taken to minimize degradation.