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Updated: Aug 18, 2026

Measurement of Heart Contractility in Isolated Adult Human Primary Cardiomyocytes
Published on: August 9, 2022
Heterogenic contractile response of rat left ventricular myocytes to beta1-adrenoceptor stimulation
Rachel Stones1, Rudolf Billeter, Simon Harrison
1School of Biomedical Sciences, University of Leeds, Worsley Building, Leeds, West Yorkshire, LS2 9JT, UK.
Abstract:
We measured the contractile response of left ventricular cardiac myocytes from female rats to selective beta(1)-adrenoceptor stimulation (isoprenaline, 10(-8) M and 10(-7) M in the presence of 10(-7) M ICI 118,551 a beta2-adrenoceptor inverse agonist). A heterogenic response to stimulation, inversely related to the extent of cell shortening prior to adrenergic stimulation, was observed. Challenge of cardiac myocytes with a selective beta1-antagonist, atenolol (10(-7) M), suggests the heterogenic response is not caused by basal beta1-adrenoceptor activity. Thus, basal myocyte contractility determines the response to beta1-adrenoceptor stimulation, this should be taken into account when experimental conditions are designed.
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