Specific endothelin binding sites in renal medullary collecting duct cells: lack of interaction with ANP binding and cGMP signalling

1992 ◽  
Vol 70 (8) ◽  
pp. 1167-1174 ◽  
Author(s):  
Peter Cernacek ◽  
Louis Legault ◽  
Duncan J. Stewart ◽  
Mortimer Levy
Keyword(s):  
Atrial Natriuretic Peptide ◽  
Natriuretic Peptide ◽  
Binding Sites ◽  
Collecting Duct ◽  
Specific Cell ◽  
Binding Studies ◽  
Single Class ◽  
High Affinity ◽  
Medullary Collecting Duct ◽  
Atrial Natriuretic

The diverse biological actions of endothelins (ET) appear to be mediated by specific cell-surface receptors. Autoradiography and membrane binding studies have shown abundant ET binding sites in the kidney. However, their expression in specific types of renal cells is unclear. We studied the binding of 125I-labelled endothelin-1 in freshly isolated cell suspensions from canine inner medullary collecting duct. Competition binding experiments revealed the presence of specific high-affinity binding sites: unlabelled ET-1 and ET-2 competed with the radioligand with an IC50 of 135 and 83 pM, respectively, while the IC50 of ET-3 and big ET-1 were 2 and 4 orders of magnitude higher, indicating the presence of ETA-type receptor. Angiotensin II, vasopressin, and atrial natriuretic peptide (ANP) did not compete for ET binding even at a concentration of 10−6 M. Saturation binding experiments showed a single class of binding sites of high density (Bmax = 56.7 ± 10.3 fmol/106 cells) and high affinity (Kd = 69.8 ± 10 pM). In contrast, ANP receptors in the same cell preparations appeared as two classes of binding sites with widely different affinity and density. The high-affinity ANP site (Kd = 311 ± 48 pM) was compatible with ANP-B (guanylate cyclase-coupled) receptor. ET-1 did not compete for this receptor. ET-1 (10−7 M) did not alter ANP-induced cGMP generation in these cells (3.8-fold increase at 10−7 M ANP), nor basal levels of cGMP. The expression by the distal tubular epithelium of specific ET-1 binding sites strongly suggests the presence of a functional receptor, which may mediate the inhibition of Na+ transport in these cells. The mechanism and the transduction pathway of this effect appear to be different and independent from those of ANP.Key words: endothelin receptor, distal collecting duct, atrial natriuretic peptide receptor, cGMP generation.

Atrial natriuretic peptide in the eel, Anguilla anguilla L.: its cardiac distribution, receptors and actions on isolated branchial cells

1992 ◽  
Vol 9 (2) ◽  
pp. 103-114 ◽  
Author(s):  
C. L. Broadhead ◽  
U. T. O'Sullivan ◽  
C. F. Deacon ◽  
I. W. Henderson
Keyword(s):  
Sodium Chloride ◽  
Atrial Natriuretic Peptide ◽  
Natriuretic Peptide ◽  
Binding Sites ◽  
Specific Binding ◽  
Anguilla Anguilla ◽  
Chloride Cells ◽  
Dependent Manner ◽  
Single Class ◽  
Atrial Natriuretic

ABSTRACT The presence of atrial natriuretic peptide (ANP) and the nature of its binding sites were studied in freshwater (FW)- and seawater (SW)-adapted eels using a heterologous analogue, that of the rat (rANP). Rat ANP-like immunoreactivity was demonstrated in the cardiac atria and ventricles of both FW and SW eels, and electron-dense ANP-like granules were observed. The atria and ventricles of FW eels contained significantly more granules than those of SW animals and, in both types, the atria were more granular than the ventricles. Specific binding sites for rANP were demonstrated by displacement and uptake experiments using labelled rANP in dispersed eel branchial cell preparations, enriched in chloride cells. The concentration of rANP required to produce a 50% inhibition of binding in FW cells was significantly lower than that in SW cells. Scatchard analyses revealed the presence of two classes of binding site in SW eel branchial cells but only a single class of receptor in FW cells. The affinity of the FW receptor was not significantly different from that of the SW high affinity site. Rat ANP stimulated the production of cyclic GMP (cGMP) in a dose-dependent manner, and both basal and stimulated levels of cGMP were significantly greater in SW branchial cells. These studies suggest that ANP is involved in the adaptation of the euryhaline eel to differing environmental salinities; the levels of the peptide in the heart alter with changing salinity, and the nature of the receptors in the sodium chloride-transporting epithelium of the gill changes in response to the need either to eliminate or to absorb sodium chloride.

Lack of effect of atrial natriuretic peptide and urodilatin on vasopressin-stimulated cyclic AMP production in microdissected rat inner medullary collecting ducts

1994 ◽  
Vol 12 (2) ◽  
pp. 149-154
Author(s):  
W J Burgess ◽  
M N Perrott ◽  
R J Balment
Keyword(s):  
Cyclic Amp ◽  
Atrial Natriuretic Peptide ◽  
Natriuretic Peptide ◽  
Collecting Duct ◽  
Rat Kidney ◽  
Absolute Magnitude ◽  
Camp Production ◽  
Collecting Ducts ◽  
Medullary Collecting Duct ◽  
Atrial Natriuretic

ABSTRACT It is unclear whether the diuretic effects of atrial natriuretic peptide (ANP) result, in part, from an inhibition of the renal actions of vasopressin. Moreover, accruing evidence suggests that the kidneys themselves may produce an ANP-like peptide, urodilatin, which shares many of the renal actions of ANP. The mechanism underlying the diuretic action of urodilatin has not yet been examined. Accordingly, we have investigated the potential modulatory actions of both ANP and urodilatin on vasopressin-stimulated cyclic AMP (cAMP) production in microdissected inner medullary collecting duct (IMCD) segments of rat kidney. ANP and urodilatin alone (at 10−8 or 10−6 m) had no demonstrable effect on cAMP accumulation in IMCD segments. Moreover, neither ANP nor urodilatin (each at 10−6 m) significantly altered either the profile or the absolute magnitude of the cAMP response stimulated by vasopressin. These findings indicate that neither ANP nor urodilatin interacts with the vasopressin-sensitive adenylate cyclase site in the rat IMCD to contribute to its diuretic actions.

scholarly journals Human basophils express interleukin-4 receptors

Blood ◽  
1990 ◽  
Vol 76 (9) ◽  
pp. 1734-1738
Author(s):  
P Valent ◽  
J Besemer ◽  
K Kishi ◽  
F Di Padova ◽  
K Geissler ◽  
...  
Keyword(s):  
Binding Sites ◽  
Interleukin 4 ◽  
Target Cells ◽  
Specific Cell ◽  
Binding Studies ◽  
Single Class ◽  
Chronic Granulocytic Leukemia ◽  
High Affinity ◽  
F Cells ◽  
Human Basophils

Interleukin-4 (IL-4), a multipotential lymphokine reputed to play an important role in the regulation of immune responses, interacts with a variety of hemopoietic target cells through specific cell surface membrane receptors. The present study was designed to investigate whether human basophils express IL-4 binding sites. For this purpose, basophils were enriched to homogeneity (93% and 98% purity, respectively) from the peripheral blood of two chronic granulocytic leukemia (CGL) donors using a cocktail of monoclonal antibodies (MoAbs) and complement. Purified basophils bound 125I-radiolabeled recombinant human (rh) IL-4 in a specific manner. Quantitative binding studies and Scatchard plot analysis revealed the presence of a single class of high affinity IL-4 binding sites (280 +/- 40 sites per cell in donor 1 and 640 +/- 45 sites per cell in donor 2) with an apparent dissociation constant, kd, of 7.12 x 10(-11) +/- 2.29 x 10(-11) and 9.55 +/- 3.5 x 10(-11) mol/L, respectively. KU812-F, a human basophil precursor cell line, was found to express a single class of 810 to 1,500 high affinity IL-4 binding sites with a kd of 2.63 to 5.54 x 10(-10) mol/L. No change in the numbers or binding constants of IL-4 receptors was found after exposure of KU812-F cells to rhIL-3 (a potent activator of basophils) for 60 minutes. No effect of rhIL-4 on 3H-thymidine uptake, release or synthesis of histamine, or expression of basophil differentiation antigens (Bsp-1, CD11b, CD25, CD40, CD54) on primary human CGL basophils or KU812-F cells was observed.

Atrial natriuretic peptide and nitric oxide signaling antagonizes vasopressin-mediated water permeability in inner medullary collecting duct cells

2009 ◽  
Vol 297 (3) ◽  
pp. F693-F703 ◽  
Author(s):  
Jens Klokkers ◽  
Patrik Langehanenberg ◽  
Björn Kemper ◽  
Sebastian Kosmeier ◽  
Gert von Bally ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Plasma Membrane ◽  
Atrial Natriuretic Peptide ◽  
Natriuretic Peptide ◽  
Water Permeability ◽  
Collecting Duct ◽  
Cell Swelling ◽  
Inner Medullary Collecting Duct ◽  
Medullary Collecting Duct ◽  
Atrial Natriuretic

AVP and atrial natriuretic peptide (ANP) have opposite effects in the kidney. AVP induces antidiuresis by insertion of aquaporin-2 (AQP2) water channels into the plasma membrane of collecting duct principal cells. ANP acts as a diuretic factor. An ANP- and nitric oxide (NO)/soluble guanylate cyclase (sGC)-induced insertion of AQP2 into the plasma membrane is reported from different models. However, functional data on the insertion of AQP2 is missing. We used primary cultured inner medullary collecting duct (IMCD) cells and digital holographic microscopy, calcein-quenching measurements, and immunofluorescence and Western blotting to analyze the effects of ANP and NO donors on AQP2 phosphorylation, membrane expression, and water permeability. While AVP led to acceleration in osmotically induced swelling, ANP had no effect. However, in AVP-pretreated cells ANP significantly decreased the kinetics of cell swelling. This effect was mimicked by 8-bromo-cGMP and blunted by PKG inhibition. Stimulation of the NO/sGC pathway or direct activation of sGC with BAY 58-2667 had similar effects to ANP. In cells treated with AVP, AQP2 was predominantly localized in the plasma membrane, and after additional incubation with ANP AQP2 was mostly localized in the cytosol, indicating an increased retrieval of AQP2 from the plasma membrane by ANP. Western blot analysis showed that ANP was able to reduce AVP-induced phosphorylation of AQP2 at position S256. In conclusion, we show that the diuretic action of ANP or NO in the IMCD involves a decreased localization of AQP2 in the plasma membrane which is mediated by cGMP and PKG.

Specific binding of atrial natriuretic peptide to rat mesenteric artery: Effect of calcium and 5-guanylylimidodiphosphate

1987 ◽  
Vol 73 (6) ◽  
pp. 573-579 ◽  
Author(s):  
Fiona Lyall ◽  
J. J. Morton
Keyword(s):  
Atrial Natriuretic Peptide ◽  
Natriuretic Peptide ◽  
Binding Sites ◽  
Mesenteric Artery ◽  
Guanosine Triphosphate ◽  
High Affinity ◽  
Dissociation Equilibrium ◽  
Rat Mesenteric Artery ◽  
Receptor Number ◽  
Atrial Natriuretic

1. High-dissociation equilibrium constant (20 pmol/l, receptor number 17 fmol/mg) and low-dissociation equilibrium constant (10 nmol/l, receptor number 5 nmol/mg) affinity binding sites for atrial natriuretic peptide have been identified in membrane preparations from rat mesenteric artery. 2. Tracer degradation was corrected for mathematically and binding data were analysed by a non-linear computer technique. 3. Non-atrial natriuretic peptide vasoactive hormones, angiotensin II, vasopressin and bradykinin, did not compete for the high-affinity site. Related peptides with either C- or N-terminal amino acids missing still competed, while peptides without an intact disulphide bridge did not compete. 4. Neither the addition nor the removal of calcium affected the affinity or density of binding sites. Also the non-hydrolysable guanosine triphosphate analogue 5-guanylylimidodiphosphate had no effect on either affinity or number of sites. 5. These results indicate the presence of a specific high-affinity vascular receptor for atrial natriuretic peptide which could interact with the hormone under physiological conditions. The mechanism of binding is uncertain but is unlikely to involve calcium- or guanosine triphosphate-associated regulatory sites.

scholarly journals Human basophils express interleukin-4 receptors

Blood ◽  
1990 ◽  
Vol 76 (9) ◽  
pp. 1734-1738 ◽  
Author(s):  
P Valent ◽  
J Besemer ◽  
K Kishi ◽  
F Di Padova ◽  
K Geissler ◽  
...  
Keyword(s):  
Binding Sites ◽  
Interleukin 4 ◽  
Target Cells ◽  
Specific Cell ◽  
Binding Studies ◽  
Single Class ◽  
Chronic Granulocytic Leukemia ◽  
High Affinity ◽  
F Cells ◽  
Human Basophils

Abstract Interleukin-4 (IL-4), a multipotential lymphokine reputed to play an important role in the regulation of immune responses, interacts with a variety of hemopoietic target cells through specific cell surface membrane receptors. The present study was designed to investigate whether human basophils express IL-4 binding sites. For this purpose, basophils were enriched to homogeneity (93% and 98% purity, respectively) from the peripheral blood of two chronic granulocytic leukemia (CGL) donors using a cocktail of monoclonal antibodies (MoAbs) and complement. Purified basophils bound 125I-radiolabeled recombinant human (rh) IL-4 in a specific manner. Quantitative binding studies and Scatchard plot analysis revealed the presence of a single class of high affinity IL-4 binding sites (280 +/- 40 sites per cell in donor 1 and 640 +/- 45 sites per cell in donor 2) with an apparent dissociation constant, kd, of 7.12 x 10(-11) +/- 2.29 x 10(-11) and 9.55 +/- 3.5 x 10(-11) mol/L, respectively. KU812-F, a human basophil precursor cell line, was found to express a single class of 810 to 1,500 high affinity IL-4 binding sites with a kd of 2.63 to 5.54 x 10(-10) mol/L. No change in the numbers or binding constants of IL-4 receptors was found after exposure of KU812-F cells to rhIL-3 (a potent activator of basophils) for 60 minutes. No effect of rhIL-4 on 3H-thymidine uptake, release or synthesis of histamine, or expression of basophil differentiation antigens (Bsp-1, CD11b, CD25, CD40, CD54) on primary human CGL basophils or KU812-F cells was observed.

Identification and quantification of human kidney atrial natriuretic peptide receptors

1995 ◽  
Vol 132 (4) ◽  
pp. 465-471 ◽  
Author(s):  
Luna Kahana ◽  
Haya Yechiely ◽  
Yoel Mecz ◽  
Aharon Lurie
Keyword(s):  
Molecular Weight ◽  
Atrial Natriuretic Peptide ◽  
Natriuretic Peptide ◽  
Binding Sites ◽  
Gel Electrophoresis ◽  
Human Kidney ◽  
Competitive Binding ◽  
Binding Studies ◽  
Natriuretic Peptide Receptors ◽  
Atrial Natriuretic

Kahana L, Yechiely H, Mecz Y, Lurie A. Identification and quantification of human atrial natriuretic peptide receptors. Eur J Endocrinol 1995;132:465–71. ISSB 0804–4643 The present study determined 125I-label atrial natriuretic peptide (ANP) binding sites in human kidney glomerular and papillary membranes. The membranes were prepared from non-malignant renal tissue obtained at nephrectomy of patients with renal carcinoma. To evaluate the proportion of ANP receptor classes ANP-R1 (ANPR-A, -B) versus ANP-R2 (ANPR-C), competitive binding studies were performed using [125I]-ANP in the presence of increasing concentrations of ANP or an internally ring-deleted analog, des(Gln116, Ser117, Gly118, Leu119, Gly120)ANP(102–121), called C-ANP, which binds selectively to ANPR-C receptors. Analysis of the competitive binding curve with ANP in glomerular membranes suggested the presence of one group of high-affinity receptors with dissociation constant Kd = 26 ± 12 pmol/l and density Bmax = 101 ± 47 nmol/kg protein. A decrease of 10–30% in Bmax with no change in Kd was obtained in the presence of excess (10−6 mol/l) C-ANP, suggesting the existence of a small amount of a second class of receptors, the ANPR-C class. The densities of ANPR-A, -B versus ANPR-C receptors in human glomeruli, calculated from competitive inhibition experiments, were 75 ± 42 and 22 ± 16 nmol/kg protein (N = 8). Autoradiography of the sodium dodecyl sulfate polyacrylamide gel electrophoresis under reducing conditions showed two bands: a highly labeled 130kD band and a weakly labeled 66kD band, both displaced by ANP. Only the 66-kD band was displaced by the C-ANP analog. Human papilla membrane, as shown by competition binding studies and SDS gel electrophoresis, presented only one class of receptors with Kd = 40 ± 23 pmol/l (mean ± SD, N = 3) and Bmax = 17 ± 6.3 nmol/kg protein. No displacement of [125I]ANP with C-ANP analog could be detected. The Kd of the binding sites in human kidney papilla was not statistically different (p > 0.05) from the Kd values of the two receptor subtypes for ANP in glomeruli. Thus, human kidney, much like that of the rat, presents: two classes, the high- (ANPR-A, -B) and low (ANPR-C)-molecular-weight receptors, in glomerular membranes; only one class, the high-molecularweight receptors, in papillary membranes. In contrast to rat kidney, the high-molecular-weight ANPR-A, -B is the dominant class in human glomerular membranes. Luna Kahana, Endocrine Laboratory, Carmel Medical Center, 7 Michal Street, Haifa 34362, Israel

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