Skip to main content
. 2001 Apr;132(8):1817–1826. doi: 10.1038/sj.bjp.0703992

Figure 1.

Figure 1

[125I]-ICYP competition curves in human left ventricular myocardium from a nonfailing heart. (A) ICYP-ICI 118.511 competition. The identification of two affinity sites allows the discrimination into 29% β2- and 71% β1-adrenoceptors. (B) ICYP-CGP 207.12A competition. 71% β1- and 29% β2-adrenoceptors are identified. The indicated concentrations (dashed lines) are used to determine binding properties of β-adrenoceptor ligands at β1- and β2-adrenoceptors specifically. (C) ICYP-isoprenaline competition in the absence and presence of 100 μmol l−1 of Gpp(NH)p. In the absence of Gpp(NH)p, 30% of adrenoceptors are in a high affinity state. This high affinity state is eliminated in the presence of Gpp(NH)p.