Noradrenaline: Central inhibitory control of blood pressure and heart rate

doi:10.1016/0014-2999(74)90188-5

European Journal of Pharmacology

Volume 29, Issue 1, November 1974, Pages 179-181

https://doi.org/10.1016/0014-2999(74)90188-5 Get rights and content

Abstract

Noradrenaline injected bilaterally into the brainstem in the area of the nucleus tractus solitarii decreased systemic arterial blood pressure and heart rate of anesthetized rats. The effect of noradrenaline was prevented by a preceding injection of the α-adrenergic blocking agent phentolamine, at the same site. The results suggest an inhibitory role of an α-adrenoceptor in the area of the nucleus tractus solitarii in the central control of blood pressure.

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Citation Excerpt :
Interestingly, destruction of noradrenergic neurons within the NTS results in marked instability of BP (Granata et al., 1983). In addition, stimulation of alpha2-adrenoceptor within the NTS promotes a strong hypotensive response (De Jong, 1974; Totola et al., 2013). These data suggest an important role for this system in BP regulation.
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Peripheral noradrenergic activity is enhanced in portal hypertension and correlates with the progression of the disease. However, little is known about the status of central norepinephrine (NE) in portal hypertension. The aim of the present work was to study the uptake of NE in several areas rich in NE in experimental prehepatic portal hypertension. The experiments were performed in vitro in several encephalic areas and nuclei, obtained according to the ‘punch-out technique’. Results showed that in portal hypertensive rats NE uptake enhanced in all areas and nuclei studies (subfornical organ, organum vasculosum lamina terminalis, area postrema, locus coeruleus and nucleus tractus solitarius). The present results suggest that these encephalic areas and brainstem nuclei may be related to the development and/or maintenance of portal hypertension in this animal model.
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Short communicationNoradrenaline: Central inhibitory control of blood pressure and heart rate

Abstract

Neuropharmacology

European J. Pharmacol.

European J. Pharmacol.

European J. Pharmacol.

An analysis of central adrenoceptors for control of cardiovascular function

Brit. J. Pharmacol.

Lack of correlation between direct and indirect measurements of arterial pressure in unanesthetized rats

Cardiovascular Res.

Short communication
Noradrenaline: Central inhibitory control of blood pressure and heart rate