Synthesis, in vitro pharmacology and biodistribution studies of new PD 156707-derived ETA receptor radioligands
摘要:
It is assumed that the regulation of cardiac endothelin (ET) receptor density is abnormal in heart diseases. From that perspective, an ET receptor radioligand is needed to assess ET receptor density in vivo. The nonpeptidyl ETA receptor antagonist PD 169390 was labelled with radioiodine to give a putative radioligand for SPECT. Labelling with [I-125]iodide and [I-123]iodide was accomplished with good to excellent radiochemical yields. The affinities of the nonradioactive reference and those of selected precursor compounds for ETA receptors were determined, using [I-125]iodine labelled endothelin-1 with mouse ventricular membranes. All employed substances exhibited potent in vitro pharmacological characteristics with K-i values comparable to that of the lead compound PD 156707. Biodistribution studies and scintigraphic imaging experiments in mice, however, showed no significant uptake of the [I-123] derivative in the heart. (c) 2005 Elsevier Ltd. All rights reserved.
Synthesis, in vitro pharmacology and biodistribution studies of new PD 156707-derived ETA receptor radioligands
摘要:
It is assumed that the regulation of cardiac endothelin (ET) receptor density is abnormal in heart diseases. From that perspective, an ET receptor radioligand is needed to assess ET receptor density in vivo. The nonpeptidyl ETA receptor antagonist PD 169390 was labelled with radioiodine to give a putative radioligand for SPECT. Labelling with [I-125]iodide and [I-123]iodide was accomplished with good to excellent radiochemical yields. The affinities of the nonradioactive reference and those of selected precursor compounds for ETA receptors were determined, using [I-125]iodine labelled endothelin-1 with mouse ventricular membranes. All employed substances exhibited potent in vitro pharmacological characteristics with K-i values comparable to that of the lead compound PD 156707. Biodistribution studies and scintigraphic imaging experiments in mice, however, showed no significant uptake of the [I-123] derivative in the heart. (c) 2005 Elsevier Ltd. All rights reserved.
A Transgenic Strategy for Analysis of the Function of the Endothelin-B-Receptor
作者:Alan Bagnall、David Webb、Yuri Kotelevtsev
DOI:10.1097/00005344-200036001-00029
日期:——
Summary:
Knockout (KO) models have provided important insights into the function of many receptors and signalling molecules. However, analysis of endothelin (ET) receptor knockouts has been complicated by the development of lethal phenotypes. In this paper, we present our strategy for examining endothelin-B- (ETB) receptor function in the context of other strategies for rescuing the lethal phenotype of ETB knockout mice.
It is assumed that the regulation of cardiac endothelin (ET) receptor density is abnormal in heart diseases. From that perspective, an ET receptor radioligand is needed to assess ET receptor density in vivo. The nonpeptidyl ETA receptor antagonist PD 169390 was labelled with radioiodine to give a putative radioligand for SPECT. Labelling with [I-125]iodide and [I-123]iodide was accomplished with good to excellent radiochemical yields. The affinities of the nonradioactive reference and those of selected precursor compounds for ETA receptors were determined, using [I-125]iodine labelled endothelin-1 with mouse ventricular membranes. All employed substances exhibited potent in vitro pharmacological characteristics with K-i values comparable to that of the lead compound PD 156707. Biodistribution studies and scintigraphic imaging experiments in mice, however, showed no significant uptake of the [I-123] derivative in the heart. (c) 2005 Elsevier Ltd. All rights reserved.