Identification of endothelin receptors in normal and hyperplasic human prostate tissues.
Specific endothelin-1 (ET1) binding sites have been demonstrated in membranes derived form normal (NP) and benign hyperplasic (BPH) human prostate using an 125I-ET1 binding assay. 125I saturation experiments and Scatchard analysis demonstrated the existence of a homogeneous population of binding sites with high affinity (Kd(app)) and density (B(max)), respectively, 106 +/- 15 pM and 1086 +/- 399 fmol/mg protein for NP (n = 5) and 168 +/- 26 pM and 964 +/- 445 fmol/mg protein for BPH (n = 5). We demonstrated the presence of two subtypes of ET1 receptors, ETA and ETB, by means of the following ET1 competitors: ET2, ET3, and BQ123 (which is selective for the ETA receptor), and IRL1620 and sarafotoxine c (S6c) (which are selective for the ETB receptor). The displacement curves allowed us to conclude that the large majority (85%) of the ET1 receptors in normal and hyperplasic human prostate are of the A subtype.
Le Brun
G
G
Department of Hormone Biochemistry, Hôpital Saint-Louis, Paris, France.
Moldovan
F
F
Aubin
P
P
Ropiquet
F
F
Cussenot
O
O
Fiet
J
J
D001667:Binding, Competitive; D002462:Cell Membrane / Q000737:chemistry / Q000378:metabolism / Q000648:ultrastructure; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D007457:Iodine Radioisotopes; D007700:Kinetics; D008024:Ligands; D008297:Male; D011467:Prostate / Q000737:chemistry* / Q000166:cytology / Q000378:metabolism; D011470:Prostatic Hyperplasia / Q000378:metabolism* / Q000473:pathology; D017466:Receptors, Endothelin / Q000032:analysis* / Q000378:metabolism
D007457:Iodine Radioisotopes; D008024:Ligands; D017466:Receptors, Endothelin