Different affinities and selectivities of endothelin-1 and endothelin-3 binding to various rat tissues.
Inhibition of [125I]endothelin-1 ([125I]ET-1) binding to membrane fractions from various rat tissues by ET-1 and endothelin-3 (ET-3) was investigated. Brain tissue demonstrated a 37-fold higher affinity for ET-1 compared to lung, while a greater than 1000-fold difference in affinity for ET-3 was observed in these two tissues. Furthermore, the ratio of the IC50 value of ET-3 to that of ET-1 in each tissue varied from approximately 2 in brain, kidney and liver to greater than 100 in heart and spleen. These experiments show that the tissues examined have different affinities as well as different selectivities for ET-1 and ET-3.
Jeng
A Y
AY
Research Dept., CIBA-GEIGY Corp., Summit, NJ 07901.
Savage
P
P
Soriano
A
A
Balwierczak
J L
JL
D000818:Animals; D001667:Binding, Competitive; D001921:Brain / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism; D016232:Endothelins / Q000378:metabolism*; D007668:Kidney / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D008168:Lung / Q000378:metabolism; D008297:Male; D009206:Myocardium / Q000378:metabolism; D051381:Rats; D011921:Rats, Inbred WKY; D013154:Spleen / Q000378:metabolism
D016232:Endothelins