Supersensitivity of 5-HT1A-autoreceptors and α2-adrenoceptors regulating monoamine synthesis in the brain of morphine-dependent rats

  title={Supersensitivity of 5-HT1A-autoreceptors and $\alpha$2-adrenoceptors regulating monoamine synthesis in the brain of morphine-dependent rats},
  author={Antoni Sastre-Coll and Susana Esteban and Jes{\'u}s A Garc{\'i}a-Sevilla},
  journal={Naunyn-Schmiedeberg's Archives of Pharmacology},
Abstract. The sensitivity of 5-HT1A serotonin receptors and α2-adrenoceptors (autoreceptors and heteroreceptors) modulating brain monoamine synthesis was investigated in rats during morphine treatment and after naloxone-precipitated withdrawal. The accumulation of 5-hydroxytryptophan (5-HTP) and 3,4-dihydroxyphenylalanine (DOPA) after decarboxylase inhibition was used as a measure of the rate of tryptophan and tyrosine hydroxylation in vivo. Acute morphine (3–100 mg/kg, 1 h) increased the… 

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