Effects of ?-adrenoceptor antagonists on the release of serotonin and noradrenaline from rat brain cortex slices

Autor: E. Schlicker, M. Göthert, F. Köstermann, R. Clausing
Rok vydání: 1983
Předmět:
Zdroj: Naunyn-Schmiedeberg's Archives of Pharmacology. 323:106-113
ISSN: 1432-1912
0028-1298
DOI: 10.1007/bf00634257
Popis: Rat brain cortex slices preincubated with3H-noradrenaline or3H-serotonin were superfused with physiological salt solution. The effects of α-adrenoceptor antagonists (phentolamine, BDF 6143, BE 2254 and rauwolscine) on the electrically evoked3H overflow and their interactions with clonidine or noradrenaline were studied. The effects of these antagonists on tritium accumulation by slices incubated with either3H-monoamine were also examined. In conclusion, when neuronal uptake was inhibited, all α-adrenoceptor antagonists investigated increased, i.e. disinhibited, the evoked3H overflow from slices labelled with3H-noradrenaline, whereas there were differences between the compounds, when neuronal noradrenaline uptake was operative; these differences were not related to their imidazoline, phenylethylamine or indolealkylamine structure or their own ability to inhibit the neuronal uptake of noradrenaline. The apparent pA2 values of the α-adrenoceptor antagonists were independent of the chemical structure of the agonists against which these values were determined (derivatives of imidazoline or phenylethylamine). The α-adrenoceptor on the serotoninergic nerve terminals of the cortex slices do not appear to be activated by endogenous noradrenaline released from neighbouring noradrenergic fibres.
Databáze: OpenAIRE
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