Opiate-Enhanced Toxicity and Noradrenergic Sprouting in Rats Treated With 6-Hydroxydopa
Document Type
Article
Publication Date
5-22-1981
Description
Because endorphin receptor activation alters the function of the central noradrenergic system, opiates may change the regenerative sprouting of neurons in response to adrenergic neurotoxins. To test this hypothesis, newborn rats were treated with several opioids and 6-hydroxydopa (6-OHDOPA) and the development of the noradrenergic system was evaluated. In combination with 6-OHDOPA morphine and naloxone potentiated the development of norepinephrine (NE) levels in the pons-medulla and cerebellum by four weeks of age. β-Endorphin, Leu- and Met-enkephalin and d-Ala2-enkephalinamide produced a similar effect in the pons-medulla. The effect of morphine was partially attenuated by naloxone. Increased cerebellar noradrenergic histofluorescent staining was observed with the morphine + 6-OHDOPA and naloxone + 6-OHDOPA treatments. Both naloxone and morphine decreased NE levels in the pons-medulla of adult rats treated with 6-OHDOPA. These results suggest that opiates and endorphins may enhance sprouting of noradrenergic neurons following neonatal treatment with 6-OHDOPA, by increasing the toxicity of this neurotoxin.
Citation Information
Harston, Craig T.; Blair Clark, M.; Hardin, Judy C.; and Kostrzewa, Richard M.. 1981. Opiate-Enhanced Toxicity and Noradrenergic Sprouting in Rats Treated With 6-Hydroxydopa. European Journal of Pharmacology. Vol.71(4). 365-373. https://doi.org/10.1016/0014-2999(81)90180-1 PMID: 6788574 ISSN: 0014-2999