Characterization of membrane melatonin receptor in mouse peritoneal macrophages: inhibition of adenylyl cyclase by a pertussis toxin-sensitive G protein

1999 ◽  
Vol 95 (1-2) ◽  
pp. 85-94 ◽  
Author(s):  
Antonio Garcı́a-Pergañeda ◽  
Juan M Guerrero ◽  
Mohammed Rafii-El-Idrissi ◽  
M Paz Romero ◽  
David Pozo ◽  
...  
Keyword(s):  
Adenylyl Cyclase ◽  
G Protein ◽  
Pertussis Toxin ◽  
Peritoneal Macrophages ◽  
Melatonin Receptor ◽  
Mouse Peritoneal Macrophages

scholarly journals Identification and characterization of a phospholipase C activity in resident mouse peritoneal macrophages. Inhibition of the enzyme by phenothiazines

1981 ◽  
Vol 197 (2) ◽  
pp. 523-526 ◽  
Author(s):  
Paul D. Wightman ◽  
Mary Ellen Dahlgren ◽  
James C. Hall ◽  
Philip Davies ◽  
Robert J. Bonney
Keyword(s):  
Phospholipase C ◽  
High Activity ◽  
Peritoneal Macrophages ◽  
Ph Optimum ◽  
Reaction Velocity ◽  
Neutral Ph ◽  
Maximum Reaction ◽  
Mouse Peritoneal Macrophages ◽  
Identification And Characterization

Resident mouse peritoneal macrophages contain a phospholipase C of high activity that is specific for phosphatidylinositol. The activity has a neutral pH optimum, is Ca2+-dependent and has a maximum reaction velocity of 525nmol/h per mg of protein. Certain phenothiazines are potent inhibitors of this activity.

Prostaglandin E2 receptors in the heart are coupled to inhibition of adenylyl cyclase via a pertussis toxin sensitive G protein

1992 ◽  
Vol 70 (1) ◽  
pp. 77-84 ◽  
Author(s):  
Richard W. Lerner ◽  
Gary D. Lopaschuk ◽  
Peter M. Olley
Keyword(s):  
Adenylyl Cyclase ◽  
G Protein ◽  
Pertussis Toxin ◽  
Binding Sites ◽  
Cyclase Activity ◽  
Prostaglandin E ◽  
Adenylyl Cyclase Activity ◽  
Adp Ribosylation ◽  
Number Of Binding Sites ◽  
Guanine Nucleotide Binding

In previous studies we have identified and isolated a prostaglandin E2 (PGE2) receptor from cardiac sarcolemmal (SL) membranes. Binding of PGE2 to this receptor in permeabilized SL vesicles inhibits adenylyl cyclase activity. The purpose of this study was to determine if the cardiac PGE2 receptor is coupled to adenylyl cyclase via a pertussis toxin sensitive guanine nucleotide binding inhibitory (Gi) protein. Incubation of permeabilized SL vesicles in the presence of 100 μM 5′-guanylamidiophosphate, Gpp(NH)p, a nonhydrolyzable analogue of GTP, resulted in a shift in [3H]PGE2 binding from two sites, one of high affinity (KD = 0.018 ± 0.003 nM) comprising 7.7% of the total available binding sites and one of lower affinity (KD = 1.9 ± 0.7 nM) to one site of intermediate affinity (KD = 0.52 ± 0.01 nM) without a significant change in the total number of PGE2 binding sites. A shift from two binding sites to one binding site in the presence of Gpp(NH)p was also observed for [3H]dihydroalprenolol binding to permeabilized cardiac SL. When permeabilized SL vesicles were pretreated with activated pertussis toxin, ADP-ribosylation of a 40- to 41-kDa protein corresponding to Gi was observed. ADP-ribosylation of SL resulted in a shift in [3H]PGE2 binding to one site of intermediate affinity without significantly changing the number of binding sites. In alamethicin permeabilized SL vesicles, 1 nM PGE2 significantly decreased (30%) adenylyl cyclase activity. Pretreatment with activated pertussis toxin overcame the inhibitory effects of PGE2. These results demonstrate that the cardiac PGE2 receptor is coupled to adenylyl cyclase via a pertussis toxin sensitive Gi protein. They also demonstrate that the interaction of this Gi protein with the PGE2 receptor is important in the regulation of PGE2 binding to its receptor.Key words: prostaglandin E2, sarcolemma, heart, adenylyl cyclase, G protein.

scholarly journals Characterization of murine peritoneal macrophage receptors for fibrin(ogen) degradation products

Blood ◽  
1986 ◽  
Vol 67 (5) ◽  
pp. 1224-1228 ◽  
Author(s):  
S Rajagopalan ◽  
SV Pizzo
Keyword(s):  
Degradation Products ◽  
Peritoneal Macrophages ◽  
Receptor System ◽  
Human Fibrinogen ◽  
Murine Peritoneal Macrophage ◽  
High Affinity ◽  
Macrophage Receptors ◽  
Low Concentrations ◽  
Mouse Peritoneal Macrophages

Abstract The binding of human fibrinogen degradation fragments D1, E, X, and Y, as well as fibrin fragment D1 dimer, to mouse peritoneal macrophages was examined. A Scatchard plot of fragment D1 binding was biphasic, suggesting two classes of receptors. Fragments D1, D1 dimer, X, and Y in low concentrations bound to macrophages with high affinity (Kd = 23 to 73 X 10(-11) mol/L). Fragment E bound specifically but at a much lower level than the other fragments. Fragment D1 was able to compete for the binding of radiolabeled fragments X and Y but not radiolabeled fragment E. These studies indicate that fragments D and E are recognized by separate receptor systems but that all of the fibrinogen degradation products that contain the D domain are recognized by the same receptor system.

scholarly journals Characterization of deoxyribonuclease activities derived from control and inflammation-associated mouse peritoneal macrophages

1984 ◽  
Vol 220 (2) ◽  
pp. 561-568
Author(s):  
G E Brown ◽  
T P Karpetsky ◽  
K Rictor ◽  
A Rahman
Keyword(s):  
Peritoneal Cavity ◽  
Peripheral Blood ◽  
Peritoneal Macrophages ◽  
Apparent Size ◽  
Blood Components ◽  
Cell Type ◽  
Specific Subset ◽  
Mouse Peritoneal Macrophages ◽  
Increased Activity

Native DNAase (deoxyribonuclease) activities derived from mouse peritoneal cavity and peripheral blood components were separated, detected, and characterized by electrophoresis into polyacrylamide gels containing DNA, followed by incubation of the gels, and staining of the substrate to reveal only the DNAase activities. Resident peritoneal macrophages contained 12 DNAase-II-like activities that were characteristic of that cell type, whereas lymphocytes and granulocytes each contained five DNAases. Induction of inflammation by peritoneal injection of thioglycollate resulted in changes in macrophage DNAase expression, including: increased total DNAase activity, a decrease in the number of activities from 12 to 11, increased activity of a specific subset of the enzymes, and a change in the apparent size of a specific subset of the enzymes. Electrophoretic and enzymic properties and sensitivity to endo-beta-N-acetylglucosaminidase H indicated that the macrophage activities probably represented charge variants of one or two parent peptide chains.

Characterization of heterotrimeric G-proteins in adult Acanthocheilonema viteae

1996 ◽  
Vol 320 (2) ◽  
pp. 459-466 ◽  
Author(s):  
GRANT Karen R. ◽  
Margaret M. HARNETT ◽  
Graeme MILLIGAN ◽  
William HARNETT
Keyword(s):  
G Protein ◽  
G Proteins ◽  
Pertussis Toxin ◽  
Eukaryotic Cells ◽  
Heterotrimeric G Proteins ◽  
Protein Subunits ◽  
Acanthocheilonema Viteae ◽  
Affinity Labelling ◽  
Α Subunits

Heterotrimeric G-proteins have been found in eukaryotic cells, from yeast to humans, but have received little attention, to date, with respect to parasitic organisms. We now present the first report of the characterization of heterotrimeric G-proteins expressed in a filarial nematode, Acanthocheilonema viteae. Using a combination of (i) affinity labelling with [α-32P]GTP; (ii) ADP-ribosylation with cholera toxin and pertussis toxin; (iii) Western blotting with a panel of anti-G-protein antibodies; and (iv) reverse transcriptase-PCR with degenerate G-protein oligonucleotide primers followed by hybridization analysis using oligonucleotides specific for individual G-protein subunits, we demonstrate that adult A. viteae expresses homologues of the β1-and/or β2-like subunits and α-subunits of the Gs, Gi, Gq and G12 subfamilies found in mammals. The role which these G-proteins may play in the biology of the organism is discussed.

scholarly journals Characterization of murine peritoneal macrophage receptors for fibrin(ogen) degradation products

Blood ◽  
1986 ◽  
Vol 67 (5) ◽  
pp. 1224-1228 ◽  
Author(s):  
S Rajagopalan ◽  
SV Pizzo
Keyword(s):  
Degradation Products ◽  
Peritoneal Macrophages ◽  
Receptor System ◽  
Human Fibrinogen ◽  
Murine Peritoneal Macrophage ◽  
High Affinity ◽  
Macrophage Receptors ◽  
Low Concentrations ◽  
Mouse Peritoneal Macrophages

The binding of human fibrinogen degradation fragments D1, E, X, and Y, as well as fibrin fragment D1 dimer, to mouse peritoneal macrophages was examined. A Scatchard plot of fragment D1 binding was biphasic, suggesting two classes of receptors. Fragments D1, D1 dimer, X, and Y in low concentrations bound to macrophages with high affinity (Kd = 23 to 73 X 10(-11) mol/L). Fragment E bound specifically but at a much lower level than the other fragments. Fragment D1 was able to compete for the binding of radiolabeled fragments X and Y but not radiolabeled fragment E. These studies indicate that fragments D and E are recognized by separate receptor systems but that all of the fibrinogen degradation products that contain the D domain are recognized by the same receptor system.

scholarly journals Purification and Structural Characterization of a Novel Water-Soluble Neutral Polysaccharide from Cantharellus cibarius and Its Immunostimulating Activity in RAW264.7 Cells

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Long Chen ◽  
Xichun Peng ◽  
Jiaying Lv ◽  
Siyin Liao ◽  
Shiyi Ou ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Functional Food ◽  
Peritoneal Macrophages ◽  
Water Soluble ◽  
Raw264.7 Cells ◽  
Molar Ratio ◽  
Immunostimulating Activity ◽  
Ft Ir ◽  
Mouse Peritoneal Macrophages

Polysaccharide is one of the important active ingredients of Cantharellus cibarius. The aims of this work were to analyze preliminary characterization and to investigate immunostimulating activity of a novel water-soluble neutral polysaccharide named JP1, which was purified from the fruiting body of Cantharellus cibarius using DEAE-FF chromatography and Sephadex G-100 chromatography. The characteristics of JP1 were determined by HPGPC, FT-IR spectra, gas chromatography, and Congo Red Method. Immunostimulating activity of JP1 was investigated in RAW264.7 cells. Results indicated that JP1 consisted of L-Arabinose, D-Mannose, D-Glucose, and D-Galactose in a molar ratio of 1 : 1.06 : 1.95 : 1.17 with a molecular weight of 336 kDa. JP1 is nontoxic to RAW264.7 cells at this concentration range (62.5–1000 μg/mL). Furthermore, JP1 can promote mouse peritoneal macrophages to secrete NO and enhance the secretion of macrophages’ cytokines IL-6 in RAW264.7 cells. These results suggested that JP1 could have potential immunostimulating activity applications as medicine or functional food.

Sign in / Sign up

Export Citation Format

Share Document