[125I]endothelin-1 binding to renal brush border and basolateral membranes.
[125I]Endothelin-1 bound with high affinity to a single site on both brush border membranes (Kd=192+/-26 pM. Bmax=314+/-49 fmol/mg) and basolateral membranes (Kd=94.7+/-3.4 pM, Bmax=612+/-107 fmol/mg) isolated from rat renal cortex. Competition binding experiments using subtype selective ligands revealed that the proportion of ET(B) to ET(A) receptors was 80:20 and 60:40 in the brush border membrane and the basolateral membrane, respectively. The results demonstrate that endothelin-1 binds to brush border membranes, and that endothelin ET(B) receptors may be involved in the previously described effects of endothelin-1 on brush border membrane Na+ transport.
Edwards
R M
RM
Department of Renal Pharmacology, SmithKline Beecham Pharmaceuticals, King of Prussia, PA 19406-0939, USA.
Trizna
W
W
Stack
E J
EJ
D000818:Animals; D002462:Cell Membrane / Q000378:metabolism; D019332:Endothelin-1 / Q000378:metabolism*; D007457:Iodine Radioisotopes; D007672:Kidney Cortex / Q000378:metabolism* / Q000648:ultrastructure; D008297:Male; D008871:Microvilli / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley
D019332:Endothelin-1; D007457:Iodine Radioisotopes