TY - JOUR
T1 - Characterization of endothelin receptor subtypes on airway smooth muscle cells
AU - Ergul, Adviye
AU - Glassberg, Marilyn K.
AU - Wanner, Adam
AU - Puett, David
N1 - Funding Information:
Received 2 May 1994; accepted 3 August 1994. This work was supported by research grants from the American Heart Association, Georgia Affiliate; the American Heart Association, Florida Affiliate (grant-in-aid 92 GIM865); the National Institutes of Health (HL20989); and the American Lung Association of Florida. A. Ergul is the recipient of an American Heart Association, Florida Affiliate, graduate student fellowship (92GSFI 4). The authors thank Carla Zoja for providing the PPET-1 cDNA, Marc E. Freeman for ET-I, Yossef Ithzak for assistance in analyzing the binding data, and Ryan Vestel and Aseem Shukla for technical assistance. Address correspondence to Dr. D. Puett, Department of Biochemistry and Molecular Biology, Life Sciences Building, University of Georgia, Athens, GA 30602, USA.
PY - 1995
Y1 - 1995
N2 - Endothelin-1 (ET-1) has constrictor and mitogenic effects on airway smooth muscle strips and cultured cells, respectively. This study addresses the type of the ET receptor subtype(s) present on ovine airway smooth muscle cells and the possibility of autocrine effects. The expression of the preproendothelin-1 gene was demonstrated by Northern analysis, and the medium obtained from these cells contained immunoreactive-ET-1. Competitive binding experiments between [125I]ET-1 and ET-1, ET-3, and two ET-receptor subtype selective-ligands, BQ-123 (ETA and sarafotoxin S6c (ETB), yielded IC50 values of 1.1 ± 0.1, 227 ± 13, 12 ± 1, and 194 ± 21 nM, respectively. ET-3 also gave a limited number of higher affinity sites. In the presence of BQ-123 (1 μ;M), the binding of [1251]ET-1 was decreased by 80-85% and the IC50 values with ET-1, ET-3, and S6c were 2.0 ± 0.4, 3.6 ± 0.6, and 1.1 ± 0.9 nM, respectively. In similar experiments with 0.1 μM sarafotoxin S6c, the respective IC50 values for ET-1 and ET-3 were 2.4 ± 0.4 and 300 ± 20 nM. These results demonstrate that about 85 ± 5% of ET-1 binding to airway smooth muscle cells is to ETA receptors and that these cells produce ET-1 in vitro.
AB - Endothelin-1 (ET-1) has constrictor and mitogenic effects on airway smooth muscle strips and cultured cells, respectively. This study addresses the type of the ET receptor subtype(s) present on ovine airway smooth muscle cells and the possibility of autocrine effects. The expression of the preproendothelin-1 gene was demonstrated by Northern analysis, and the medium obtained from these cells contained immunoreactive-ET-1. Competitive binding experiments between [125I]ET-1 and ET-1, ET-3, and two ET-receptor subtype selective-ligands, BQ-123 (ETA and sarafotoxin S6c (ETB), yielded IC50 values of 1.1 ± 0.1, 227 ± 13, 12 ± 1, and 194 ± 21 nM, respectively. ET-3 also gave a limited number of higher affinity sites. In the presence of BQ-123 (1 μ;M), the binding of [1251]ET-1 was decreased by 80-85% and the IC50 values with ET-1, ET-3, and S6c were 2.0 ± 0.4, 3.6 ± 0.6, and 1.1 ± 0.9 nM, respectively. In similar experiments with 0.1 μM sarafotoxin S6c, the respective IC50 values for ET-1 and ET-3 were 2.4 ± 0.4 and 300 ± 20 nM. These results demonstrate that about 85 ± 5% of ET-1 binding to airway smooth muscle cells is to ETA receptors and that these cells produce ET-1 in vitro.
KW - Airway smooth muscle cells
KW - Endothelin
KW - Endothelin receptors
UR - http://www.scopus.com/inward/record.url?scp=0029039768&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0029039768&partnerID=8YFLogxK
U2 - 10.3109/01902149509023719
DO - 10.3109/01902149509023719
M3 - Article
C2 - 7621780
AN - SCOPUS:0029039768
SN - 0190-2148
VL - 21
SP - 453
EP - 468
JO - Experimental Lung Research
JF - Experimental Lung Research
IS - 3
ER -