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PubMed · 6319155

Ganglionic blockade by d-amphetamine.

D Christ
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Abstract

The actions of d-amphetamine on ganglionic transmission in the isolated stellate ganglion of the hamster were observed. Blockade of the compound action potential by d-amphetamine had a slow onset with an onset half-time of 2-5 min. The concentration-blockade relationship for d-amphetamine was not shifted by phentolamine (10(-5) M) or propranolol (10(-6) M). The blockade was frequency-dependent, and the frequency-dependence was suppressed by atropine (10(-6) M). It was suggested that the frequency-dependence of d-amphetamine involved a muscarinic mechanism. In support of this suggestion, the afterdischarges from repetitive stimulation in hexamethonium were relatively insensitive to d-amphetamine. Also afterdischarges could be recorded after repetitive stimulation in 10(-4) M d-amphetamine, without hexamethonium. High concentrations of d-amphetamine (10(-3) M) induced discharges in the postganglionic nerve and potentiated the discharges from the cholinergic agonists, DMPP and McN-A-343. Tolerance rapidly developed to these stimulatory effects. These results indicate that ganglionic blockade by d-amphetamine is produced by a different mechanism than ganglionic blockade by the catecholamines.

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Action PotentialsAnimalsCricetinaeDextroamphetamineDrug InteractionsElectric StimulationMesocricetusNeural InhibitionParasympathomimeticsStellate GanglionSynaptic TransmissionJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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D Christ. 1983-12-09. Ganglionic blockade by d-amphetamine.. https://doi.org/10.1016/0014-2999(83)90538-1

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