Distribution of common peptide YY-neuropeptide Y receptor along rat intestinal villus-crypt axis

1990 ◽  
Vol 258 (5) ◽  
pp. G753-G759 ◽  
Author(s):  
T. Voisin ◽  
C. Rouyer-Fessard ◽  
M. Laburthe
Keyword(s):  
Neuropeptide Y ◽  
Peptide Yy ◽  
Dissociation Constants ◽  
Binding Capacity ◽  
Cell Populations ◽  
Scatchard Analysis ◽  
Binding Data ◽  
Active Concentration ◽  
Camp Levels ◽  
Crypt Cells

Rat small intestinal epithelium is equipped with peptide YY (PYY)-preferring receptors, which also recognize neuropeptide Y (NPY) with high affinity. We therefore examined the distribution of PYY-NPY receptors along the villus-crypt axis after separation of mature villus cells from proliferative crypt cells. Specific 125I-labeled PYY binding was nine times higher in crypt cells than in villus cells. This was not due to differential degradation of PYY or PYY binding sites by the two cell populations. Rather, Scatchard analysis of equilibrium binding data showed that binding capacity (Bmax) of receptors increased from villus to crypt. Bmax were 166 +/- 36 and 21 +/- 3 fmol/mg protein, and dissociation constants (Kd) were 0.10 +/- 0.02 and 0.05 +/- 0.02 nM in crude membranes prepared from crypt and villus cells, respectively. For all cell populations, NPY and rat pancreatic polypeptide were 8- and 1,800-fold less potent than PYY in inhibiting 125I-PYY binding, respectively. Therefore, receptors appear to be PYY preferring along the entire villus-crypt axis. Both peptides (at the maximally active concentration of 1 microM) reduced vasoactive intestinal peptide (VIP)-stimulated adenosine 3',5'-cyclic monophosphate (cAMP) by 50% in crypt cells. PYY was four to six times more potent than NPY in agreement with the expression of a PYY-preferring receptor. By contrast, neither PYY nor NPY altered VIP-stimulated cAMP levels in villus cells. These results indicate that PYY-preferring receptors, negatively coupled to the cAMP production system, are preferentially expressed in crypt cells where intestinal ionic secretion is believed to take place.

Downregulation of hepatocyte P2-purinoceptor binding capacity after trauma-hemorrhage/resuscitation

1994 ◽  
Vol 266 (6) ◽  
pp. R1804-R1809
Author(s):  
M. S. Mahmoud ◽  
P. Wang ◽  
S. R. Hootman ◽  
S. S. Reich ◽  
I. H. Chaudry
Keyword(s):  
Dissociation Constants ◽  
Binding Capacity ◽  
Isolated Hepatocytes ◽  
Scatchard Analysis ◽  
Midline Laparotomy ◽  
Binding Characteristics ◽  
Shed Blood ◽  
P2 Purinoceptors ◽  
Altered Glucose ◽  
Affinity Receptor

Although P2-purinoceptors play an important role in the regulation of liver metabolism under normal conditions, it is not known if trauma-hemorrhage and resuscitation have any effects on such receptors. To study this, we performed a 5-cm midline laparotomy (i.e., trauma induced) on rats and then bled them to and maintained them at a mean arterial pressure of 40 mmHg until 40% of maximum bleedout volume was returned in the form of Ringer lactate (RL). The animals were then resuscitated with 3x the volume of shed blood with RL over 45 min followed by 2x RL over 95 min. Hepatocytes were isolated at the time of maximum bleedout or at 0, 4, 17, and 27 h after the completion of crystalloid resuscitation. P2-purinoceptor binding characteristics were determined in the isolated hepatocytes by using [alpha-35S]ATP. Scatchard analysis revealed high- and low-affinity components of P2-purinoceptors in hepatocytes from sham-operated as well as hemorrhaged and resuscitated animals. The maximum binding capacity (Bmax) of the high-affinity receptor component decreased at the time of maximum bleedout and at 4, 17, and 27 h after resuscitation. In addition to this, the Bmax of low-affinity receptor components also decreased at 4-27 h after resuscitation. In contrast, the dissociation constants of both receptor components were not altered. Because hemorrhagic shock produces abnormalities in glucose metabolism, the downregulation of hepatocyte P2-purinoceptor Bmax may be responsible for the altered glucose homeostasis under such conditions.

Mineralocorticoid and glucocorticoid receptor steroid binding and localization in colonic cells

1994 ◽  
Vol 266 (3) ◽  
pp. C729-C740 ◽  
Author(s):  
G. Schulman ◽  
N. M. Robertson ◽  
I. B. Elfenbein ◽  
D. Eneanya ◽  
G. Litwack ◽  
...  
Keyword(s):  
Nuclear Translocation ◽  
Dissociation Constants ◽  
Intracellular Localization ◽  
Distal Colon ◽  
Rat Colon ◽  
Leucine Incorporation ◽  
Scatchard Analysis ◽  
Trypan Blue Exclusion ◽  
Colonic Cells ◽  
Crypt Cells

In rat colon epithelium glucocorticoids and mineralocorticoids regulate Na transport by binding to distinct receptors and stimulating different pathways. The distribution and intracellular localization of mineralocorticoid (MR) and glucocorticoid (GR) receptors in colonic Na-absorbing surface cells and Cl-secreting crypt cells is unknown. Surface and crypt cells were sequentially isolated from rat distal colon by EDTA chelation and mechanical dissociation. Cell viability was confirmed by trypan blue exclusion and low rates of 2',7'-bis(2-carboxyethyl)-5(6)-carboxylfluorescein leak. Histologic examination, alkaline phosphatase activity, and rates of [3H]leucine incorporation confirmed separation of surface from crypt cells. Scatchard analysis of [3H]aldosterone and [3H]triamcinolone acetonide binding demonstrated that the number of MR decreased from 7,228 +/- 1,067 in surface to 2,299 +/- 434 receptors/cell in crypt cells, whereas the number of GR increased from 20,857 +/- 4,241 in surface to 58,598 +/- 8,207 receptors/cell in crypt cells. The dissociation constants were 2.8 +/- 0.4 nM for the MR and 12 +/- 3 nM for the GR. Indirect immunofluorescence using the specific anti-MR antibody hMRsN and the anti-GR antibody BuGR-2 demonstrated that both unliganded receptors were cytoplasmic and translocated to the nucleus after hormone binding. These data indicate that both surface and crypt cells are potentially responsive to mineralocorticoids and glucocorticoids and that both the MR and GR require hormone for nuclear translocation.

Induction of calcitonin receptor expression by glucocorticoids in T47D human breast cancer cells

1991 ◽  
Vol 130 (2) ◽  
pp. 321-326 ◽  
Author(s):  
M. Kurokawa ◽  
V. P. Michelangeli ◽  
D. M. Findlay
Keyword(s):  
Time Course ◽  
Binding Capacity ◽  
Receptor Expression ◽  
Scatchard Analysis ◽  
Continuous Exposure ◽  
Calcitonin Receptor ◽  
Binding Data ◽  
Receptor Number ◽  
Steroid Binding

ABSTRACT When T47D cells were maintained long term in medium containing 0·1 μmol cortisol/l, calcitonin receptor (CTR) expression was stimulated compared with the very low levels of binding in untreated cells grown from frozen stocks. The time-course of the appearance of CTR following treatment with cortisol was slow, requiring up to 3 weeks of continuous exposure of the cells to the steroid. Binding capacity of control cells also increased slowly with time in culture, but after 3 months was only 20–30% of that in cells continuously treated with cortisol. Removal of cortisol resulted in rapid loss of CTR so that binding was reduced to ∼ 50% of treated cell levels within 1 week of removal. Scatchard analysis of the binding data showed that the increased binding capacity induced by cortisol was due solely to a change in average receptor number per cell, with no change in receptor affinity. That this induction of CTR was due to a glucocorticoid effect was shown by the more rapid (< 96 h) and more potent (< 1 nmol/l) action of dexamethasone than of cortisol. In addition, induction was inhibited by the glucocorticoid inhibitor RU486. The induced receptors were shown to be functional, since salmon calcitonin-stimulated adenylate cyclase was induced in parallel with CTR. These results indicate that glucocorticoids are potential regulators of the CTR. Journal of Endocrinology (1991) 130, 321–326

Characterization of PGE2 receptors in isolated rabbit colonic crypt cells

1995 ◽  
Vol 268 (2) ◽  
pp. G270-G275 ◽  
Author(s):  
F. R. Homaidan ◽  
L. Zhao ◽  
R. Burakoff
Keyword(s):  
Binding Sites ◽  
Dissociation Constants ◽  
Distal Colon ◽  
Scatchard Analysis ◽  
Colonic Crypt ◽  
Effector Cells ◽  
Colonic Crypts ◽  
Specific Receptors ◽  
Crypt Cells

The physiological effects of prostaglandins (PG) are mediated through their interactions with specific receptors on effector cells. In this study the properties of PGE2 receptors in the rabbit distal colon were examined. We report the presence of specific, saturable, and high-affinity binding sites of PGE2 of the EP2 subtype in isolated colonic crypts. Scatchard analysis revealed the presence of two binding sites with dissociation constants of 0.3 and 10.8 nM and corresponding maximum number of receptors of 15 and 134 fmol/10(6) cells. From competition experiments in the presence of guanosine 5'-O-(3-thiotriphosphate), PGE2 binding was decreased, suggesting that the receptor is coupled to a G protein. No PGE2 binding sites were detected in surface cells. Levels of adenosine 3',5'-cyclic monophosphate (cAMP) were measured in isolated epithelial cells after being exposed to different concentrations of PGE2. cAMP levels were significantly increased only in the crypt cells when exposed to PGE2. These data provide the first demonstration for the existence of PGE2 receptors on colonic crypt cells, which when activated lead to increased levels of cAMP.

Evidence for specific binding and stimulatory effects of recombinant human erythropoietin on isolated adult rat Leydig cells

1992 ◽  
Vol 127 (5) ◽  
pp. 459-465 ◽  
Author(s):  
Roberto Mioni ◽  
Francesco Gottardello ◽  
Paola Bordon ◽  
Gianni Montini ◽  
Carlo Foresta
Keyword(s):  
Recombinant Human Erythropoietin ◽  
Leydig Cells ◽  
Binding Capacity ◽  
Specific Binding ◽  
Scatchard Analysis ◽  
Maximal Effect ◽  
Adult Rat ◽  
Testosterone Production ◽  
Human Erythropoietin ◽  
Binding Data

The presence of specific binding of recombinant human erythropoietin and its effect on testosterone production were evaluated in isolated intact adult rat Leydig cells. Maximal specific binding was observed after 135 min incubation at 34°C. Scatchard analysis of the binding data revealed two distinct classes of binding sites for [125I]-recombinant human erythropoietin with dissociation constant of(Kd1) 1.9× 10−10mol/l and (Kd2) 1.37× 10−8 mol/l respectively and binding capacity of (Bmax1) 12.3fmol/l 106 cells and (Bmax2) 42.8 fmol/106 cells, respectively. GnRH, hCG, IGF-I and EGF did not induce any modification of recombinant human erythropoietin-specific binding. Recombinant human erythropoietin added to isolated adult rat Leydig cells exerted a stimulatory effect on testosterone production reaching its maximal effect at the dose of 10−10 mol/l (testosterone production from 14.9±1.7 to 45.1±6.2 pmol/106 cells/3 h). Addition of anti-recombinant human erythropoietin serum completely blocked the recombinant human erythropoietin-stimulated testosterone production. These results show that purified adult rat Leydig cells possess recombinant human erythropoietin specific binding, and suggest that this glycoprotein directly influences rat Leydig steroidogenesis.

Neurotensin and neuromedin N stimulate mucin output from human goblet cells (Cl.16E) via neurotensin receptors

1992 ◽  
Vol 262 (3) ◽  
pp. G470-G476 ◽  
Author(s):  
C. Augeron ◽  
T. Voisin ◽  
J. J. Maoret ◽  
B. Berthon ◽  
M. Laburthe ◽  
...  
Keyword(s):  
Cell Membranes ◽  
Binding Capacity ◽  
Regulatory Peptides ◽  
Scatchard Analysis ◽  
Terminal Part ◽  
Neurotensin Receptors ◽  
Binding Data ◽  
Mucin Release ◽  
Neuromedin N ◽  
Dissociation Constant Kd

The stably differentiated human intestinal goblet cell line Cl.16E was used to study the effects of two structurally related regulatory peptides, neurotensin (NT) and neuromedin N (NN), on mucus secretion. NT and NN stimulated rapid release of mucins from filter-grown Cl.16E cells, this effect being dose related with a mean effective dose of 36 nM for NT and 422 nM for NN. The order of potency of NT, three NT fragments corresponding to the NH2-terminal part [NT-(1-11)] or to the COOH-terminal part [NT-(8-13) and NT-(9-13)], and NN in promoting mucin release and in inhibiting 125I-labeled NT binding to Cl.16E cell membranes was identical with NT greater than or equal to NT-(8-13) greater than NN greater than NT-(9-13) much greater than NT-(1-11) supporting the hypothesis that NT and NN stimulate mucin output through interaction with a common NT-preferring receptor. Scatchard analysis of equilibrium binding data showed one population of NT binding sites in Cl.16E cell membranes with the following characteristics: binding capacity (Bmax) was 141 fmol/mg of protein and dissociation constant (Kd) was 1.00 nM.(ABSTRACT TRUNCATED AT 250 WORDS)

Increased secretion of erythropoietin in human renal carcinoma cells in response to atrial natriuretic factor

1990 ◽  
Vol 259 (3) ◽  
pp. C427-C431 ◽  
Author(s):  
M. Ueno ◽  
I. Rondon ◽  
B. Beckman ◽  
J. Brookins ◽  
J. Nakashima ◽  
...  
Keyword(s):  
Atrial Natriuretic Factor ◽  
Renal Carcinoma ◽  
Binding Capacity ◽  
Carcinoma Cells ◽  
Scatchard Analysis ◽  
Single Class ◽  
Natriuretic Factor ◽  
Binding Data ◽  
Cell Incubation ◽  
Atrial Natriuretic

The present studies were undertaken to assess the effects of atrial natriuretic factor (ANF) on erythropoietin (Ep) secretion in Ep-producing renal carcinoma (RC) cells using a sensitive radioimmunoassay for Ep. Human ANF produced a significant dose-related increase in Ep secretion at concentrations of 10(-7) and 10(-6) M when compared with vehicle controls. ANF (greater than or equal to 10(-9) M) also significantly increased the intracellular guanosine 3',5'-cyclic monophosphate (cGMP) concentration after 5-min incubation with the RC cells. Scatchard analysis of the human 125I-labeled ANF binding data indicated that the RC cells contain a single class of binding sites with a dissociation constant (Kd) of 93 +/- 1 pM and a binding capacity of 2,190 +/- 750 sites/cell. Incubation of the RC cells with 8-bromo-cGMP in concentrations of 10(-7)-10(-5) M also produced a significant dose-related enhancement of Ep secretion. These findings suggest that the increase in Ep secretion in response to ANF can be attributed, at least in part, to activation of guanylate cyclase, which is coupled to specific ANF receptors on the RC cell.

Abnormal levels of neuropeptide Y and peptide YY in colon in the irritable bowel syndrome (IBS)

2001 ◽  
Vol 120 (5) ◽  
pp. A753-A754
Author(s):  
M SIMREN ◽  
G RINGSTROM ◽  
P STOTZER ◽  
H ABRAHAMSSON ◽  
E BJOMSSON
Keyword(s):  
Irritable Bowel Syndrome ◽  
Neuropeptide Y ◽  
Peptide Yy ◽  
Irritable Bowel

Calcium and the Fc Receptor on Human Platelets

1987 ◽  
Vol 57 (03) ◽  
pp. 298-301
Author(s):  
William F Clark ◽  
Gerald J M Tevaarwerk ◽  
Bruce D Reid ◽  
Suzanne Hall ◽  
Anita Caveney ◽  
...  
Keyword(s):  
Specific Binding ◽  
Normal Subjects ◽  
Human Platelets ◽  
Fc Receptor ◽  
Normal Male ◽  
Scatchard Analysis ◽  
Normal Female ◽  
Apparent Difference ◽  
Binding Data ◽  
Direct Binding

SummaryWe have described the calcium dependence of the IgG Fc receptor (Fc-R) on human platelets by analyzing the direct binding of radiolabelled Fc fragments, monomers and dimers of IgG. Specific binding to platelets was undetectable at 37° C in a calcium-free preparation but readily detected when calcium was restored. Scatchard analysis of the binding data for the calcium-restored platelets permitted calculation of the available Fc-R and the Ka of binding for the different IgG ligands. The mean Ka of binding for 12 normal subjects varied from 107 to 108 L/M, with an equal receptor number measured by Fc fragments and dimers of IgG, but a lesser amount for monomeric IgG. There was no apparent difference in Fc-R number for platelets from 6 normal male versus 6 normal female subjects.At 4° C binding was detectable for dimers and polymers of IgG in a calcium-free preparation and this was markedly increased with recalcification. Thus, our data are consistent with an Fc receptor population on human platelets whose avidity for binding is significantly enhanced in a calcium-restored medium.

The Role of Neuropeptide Y and Peptide YY in the Development of Obesity via Gut-brain Axis

2019 ◽  
Vol 20 (7) ◽  
pp. 750-758 ◽  
Author(s):  
Yi Wu ◽  
Hengxun He ◽  
Zhibin Cheng ◽  
Yueyu Bai ◽  
Xi Ma
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Neuropeptide Y ◽  
Metabolic Diseases ◽  
Peptide Yy ◽  
Vital Role ◽  
Gut Peptides ◽  
Nonalcoholic Fatty Liver ◽  
The Central Nervous System

Obesity is one of the main challenges of public health in the 21st century. Obesity can induce a series of chronic metabolic diseases, such as diabetes, dyslipidemia, hypertension and nonalcoholic fatty liver, which seriously affect human health. Gut-brain axis, the two-direction pathway formed between enteric nervous system and central nervous system, plays a vital role in the occurrence and development of obesity. Gastrointestinal signals are projected through the gut-brain axis to nervous system, and respond to various gastrointestinal stimulation. The central nervous system regulates visceral activity through the gut-brain axis. Brain-gut peptides have important regulatory roles in the gut-brain axis. The brain-gut peptides of the gastrointestinal system and the nervous system regulate the gastrointestinal movement, feeling, secretion, absorption and other complex functions through endocrine, neurosecretion and paracrine to secrete peptides. Both neuropeptide Y and peptide YY belong to the pancreatic polypeptide family and are important brain-gut peptides. Neuropeptide Y and peptide YY have functions that are closely related to appetite regulation and obesity formation. This review describes the role of the gutbrain axis in regulating appetite and maintaining energy balance, and the functions of brain-gut peptides neuropeptide Y and peptide YY in obesity. The relationship between NPY and PYY and the interaction between the NPY-PYY signaling with the gut microbiota are also described in this review.

Sign in / Sign up

Export Citation Format

Share Document