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Updated: Aug 16, 2026

Disrupting Reconsolidation of Fear Memory in Humans by a Noradrenergic β-Blocker
Published on: December 18, 2014
[Acute tolerance to noradrenaline ("noradrenaline escape")]
Abstract:
The decline in arterial systemic blood pressure which follows the initial rise during i.v. perfusion of L-noradrenaline in normal rats has been compared with the same type of decline induced by metaraminol or phenylephrine, both alpha-sympathomimetic drugs (acute tolerance or escape). Vasoconstrictor activity of noradrenaline in shot i.v. injection is regularly decreased when acute tolerance develops. This hyposensitivity to NA indicates that a change in alpha-receptor affinity for circulating NA may explain the acute tolerance as well as the noradrenaline escape.
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