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Updated: Aug 19, 2026

Rodent Working Heart Model for the Study of Myocardial Performance and Oxygen Consumption
Published on: August 16, 2016
Cardiac chamber-specific beta-adrenoceptor regulation and sympathetic innervation
1National Heart and Lung Institute, London, UK.
Abstract:
We assessed by radioligand binding techniques the effect of cardiac failure on beta-adrenoceptor density in 5 hearts from patients undergoing repeat transplantation and 5 normal (unused donor) hearts. Right ventricular total and subtype beta-adrenoceptors in the denervated repeat-transplant hearts were down-regulated compared with the normally innervated controls. Within the denervated hearts, beta 1-adrenoceptors were selectively down-regulated in the right ventricle compared with the left ventricle. Tissue noradrenaline content confirmed sympathetic denervation in the transplanted hearts. Thus, regional sympathetic innervation is not necessary for chamber-specific beta-adrenoceptor down-regulation; other mechanisms for this process should be sought.
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