scholarly journals Effects of temperature, metabolic inhibitors and some other factors on fluid-phase and adsorptive pinocytosis by rat peritoneal macrophages

1979 ◽  
Vol 180 (3) ◽  
pp. 567-571 ◽  
Author(s):  
M K Pratten ◽  
J B Lloyd
Keyword(s):  
Low Temperature ◽  
Energy Supply ◽  
Cytochalasin B ◽  
Fluid Phase ◽  
Peritoneal Macrophages ◽  
Metabolic Energy ◽  
Metabolic Inhibitors ◽  
Dibutyryl Cyclic Amp ◽  
Effects Of Temperature

Low temperature, NaF and 2,4-dinitrophenol could each abolish the pinocytic uptake of 125I-labelled poly(vinylpyrrolidone) or colloidal [198Au]gold by rat peritoneal macrophages cultured in vitro. Cytochalasin B caused only partial inhibition, even at 10 microgram/ml, and colchicine (10 or 25 microgram/ml) inhibited uptake of colloidal [198Au]gold much more than that of 125I-labelled poly(vinylpyrrolidone). Dibutyryl cyclic AMP and ouabain were without effect on uptake of 125I-labelled poly(vinylpyrrolidone), and slight stimulation was seen with ATP and theophylline. Uptake of 125I-labelled poly(vinylpyrrolidone) was abolished by EGTA (5mM), but restored by adding CaCl2 (5mM). The results appear not to support the conventional criteria for the division of pinocytic phenomena into macropinocytosis, requiring a metabolic energy supply and cytoskeletal components, and micropinocytosis, requiring neither.

Phagocytic uptake of latex beads by rat peritoneal macrophages: Comparison of morphological and radiochemical assay methods

1984 ◽  
Vol 4 (6) ◽  
pp. 497-504 ◽  
Author(s):  
Margaret K. Pratten ◽  
John B. Lloyd
Keyword(s):  
Culture Media ◽  
Fluid Phase ◽  
Peritoneal Macrophages ◽  
Metabolic Inhibitors ◽  
Similar Data ◽  
Radiochemical Method ◽  
Latex Particles ◽  
Latex Beads ◽  
Phagocytic Uptake

Contrary to previous reports, commercially available 1000-nm latex beads were found to be labelable with125I, yielding a product that retained its radiolabel on storage at 4°C and when incubated in tissue-culture media. This finding permitted a radiochemical method to measure phagocytic uptake of latex particles by rat peritoneal macrophages cultured in vitro, and a direct comparison with the established method of particle counting by light microscopy. The two methods yielded closely similar data, demonstrating that the (much more convenient) radiochemical method for quantitating phagocytic uptake is both feasible and reliable. The kinetics of phagocytic uptake of the latex particles and the effect of low temperature and metabolic inhibitors (sodium fluoride and 2,4-dinitrophenol) are described. Ongoing phagocytosis did not alter the rate of fluid-phase pinocytosis by macrophages.

scholarly journals Mitochondrial respiration and cytochrome c inhibition by sulfide in peritoneal macrophages in vitro: effects of temperature and pH

Critical Care ◽  
2010 ◽  
Vol 14 (Suppl 1) ◽  
pp. P6 ◽  
Author(s):  
M Groeger ◽  
F Wagner ◽  
K Baumgart ◽  
M Huber-Lang ◽  
M Knoeferl ◽  
...  
Keyword(s):  
Cytochrome C ◽  
Mitochondrial Respiration ◽  
Peritoneal Macrophages ◽  
Effects Of Temperature ◽  
In Vitro Effects

scholarly journals Characteristics of Ion Transport in Kidney Cortex of Mammalian Hibernators

1966 ◽  
Vol 49 (6) ◽  
pp. 1221-1239 ◽  
Author(s):  
J. S. WILLIS
Keyword(s):  
Low Temperature ◽  
Initial Rate ◽  
Ground Squirrels ◽  
Metabolic Inhibitors ◽  
Kidney Cortex ◽  
Cortex Slices ◽  
State Concentration ◽  
Kidney Cortex Slices ◽  
K Transport

Slices of kidney cortex of two species of hibernating mammals (hamsters and ground squirrels) have been leached of K, and their subsequent ability to reaccumulate K in vitro has been determined at temperatures between 38° and 0°C. At 5°C (body temperature of a hibernating mammal) uptake is appreciable in kidney cortex of both species. In the kidney cortex of hamsters, for example, the tissue K of slices incubated at 5°C reaches the same steady-state concentration after 2 hours that is observed in slices at 38°C after 20 minutes. At 0°C there is also a measurable uptake. This K transport is blocked by metabolic inhibitors and, in ground squirrel kidneys, by ouabain. In kidney cortex slices from guinea pigs net K accumulation is slight at 5°C and absent at 0°C. The initial rapid uptake of K at 38°C occurs at the same rate in kidney cortex slices of hamsters as in those of rabbits. Lowering the temperature of incubation decreases this initial rate of uptake in hamster kidney slices with a Q10 of 1.8 between 38° and 15° and of 5.7 between 15° and 0°C. In hamsters this uptake of K has been shown to require the outward extrusion of Na. Conversely, about half of the outward extrusion of Na requires K in the medium, while the remainder appears to be independent of K. The conclusions warranted are that kidney cells of hibernators possess an unusual ability to transport ions at low temperature, that this ability does not depend upon a more rapid rate at higher temperatures, and that the characteristics of transport at low temperature are qualitatively similar to those at 38°C in cells of nonhibernators.

Exchange diffusion and runout of Diodrast-I131 from renal tissue in vitro

1961 ◽  
Vol 201 (2) ◽  
pp. 309-317 ◽  
Author(s):  
William B. Kinter ◽  
Allen L. Cline
Keyword(s):  
Low Temperature ◽  
Organic Acids ◽  
Renal Tissue ◽  
Metabolic Inhibition ◽  
Metabolic Inhibitors ◽  
Lipid Solubility ◽  
Facilitated Diffusion ◽  
Complex Membrane ◽  
Tubular Transport

Runout of preaccumulated Diodrast-I131 from isolated goldfish kidneys was investigated with particular attention to metabolic inhibition, competition by related organic acids, and low temperature. Addition of metabolic inhibitors, such as cyanide, to medium bathing the tissue increased Diodrast runout, i.e., rate of net movement into medium. In conjunction with these same inhibitors, competitors either decreased or further increased runout, e.g., probenecid exhibited the former and p-aminohippurate (PAH) the latter action. In the absence of metabolic inhibition, increasing medium concentration of a given competitor first increased and then decreased runout. Low temperature decreased control runout as well as actions of competitors and metabolic inhibitors. Differences in lipid solubility correlate with differences in action of particular competitors. These results are interpreted as evidence for a complex membrane process mediating outward Diodrast movement, e.g., a carrier cycle which exhibits characteristics of both exchange and facilitated diffusion. Speculatively, such a process could be the basis for both active secretion and reabsorption, i.e., bidirectional tubular transport of organic acids.

Effects of colchicine on endocytosis of horseradish peroxidase by rat peritoneal macrophages

1980 ◽  
Vol 45 (1) ◽  
pp. 59-71 ◽  
Author(s):  
A. Piasek ◽  
J. Thyberg
Keyword(s):  
Horseradish Peroxidase ◽  
Digestive Enzymes ◽  
Cytochalasin B ◽  
Fluid Phase ◽  
Peritoneal Macrophages ◽  
The Other ◽  
Fluid Phase Endocytosis ◽  
Cytoplasmic Microtubules ◽  
Endocytic Vesicles ◽  
Cytoplasmic Complex

Horseradish peroxidase (HRP) was used as an exogenous marker to study the effects of microtubule-disruptive drugs on endocytosis in cultures of thioglycollate-elicited rat peritoneal macrophages. Colchicine and vinblastine, but not lumicolchicine or cytochalasin B, reduced HRP uptake by about 30–40%. However, as determined by stereological measurements, the size of the HRP-containing compartment within the cells remained unaltered. In both control cells and cells treated with colchicine or vinblastine the HRP-reactive vesicles were preferentially located close to the dictyosomes (stacks of cisternae) despite the fact that the Golgi complex was disorganized in the treated cells. These results suggest that intact cytoplasmic complex was disorganized in the treated cells. These results suggest that intact cytoplasmic microtubules are required to maintain a normal rate of fluid phase endocytosis in macrophages. On the other hand, it seems as if microtubules are not necessary for the translocation of newly formed endocytic vesicles/lysosomes to the dictyosomes, from which they probably are supplied with digestive enzymes.

scholarly journals Hydrogen peroxide release from mouse peritoneal macrophages: dependence on sequential activation and triggering.

1977 ◽  
Vol 146 (6) ◽  
pp. 1648-1662 ◽  
Author(s):  
C F Nathan ◽  
R K Root
Keyword(s):  
Superoxide Anion ◽  
Cytochalasin B ◽  
Indirect Evidence ◽  
Peritoneal Macrophages ◽  
Ionophore A23187 ◽  
Sequential Activation ◽  
Hydrogen Peroxide Release ◽  
Activating Agent ◽  
Mouse Peritoneal Macrophages

Using a specific and sensitive fluorometric assay, the H2O2 release from as few as 2 X 10(5) mouse peritoneal macrophages could be detected continuously and quantitated. It is emphasized that the assay measured H2O2 release, not production. Induction of H2O2 release required sequential application of two stimuli: the administration of an activating agent to the mice from 4 days to 10 wk before all harvest, and the exposure of the cells in vitro to a triggering agent. BCG was most effective as an activating agent, resulting in peritoneal macrophages which could be triggered to release H2O2 almost as copiously (8 nmol/10(6) macrophages per 5 min) as mouse peritoneal PMN (9 NMOL/10(6) PMN per 5 min). Casein and C. parvum could also serve as activators, but thioglycollate and FCS were ineffective after single injections. PMA was a potent triggering agent, resulting in a maximal rate of H2O2 release after a latency of about 40 s for cells in suspension. Other triggering agents included the ionophore A23187, concanavalin A in the presence of cytochalasin B, and phagocytosis. H2O2 release could be attributed to macrophages and PMN in peritoneal cell suspensions or in preparations of adherent peritoneal cells, but not to lymphocytes. Indirect evidence suggested that the H2O2 detected was formed from superoxide anion. These observations appear to justify renewed interest in the idea that H2O2 may be important in macrohpage antimicrobial and antitumor mechanisms.

scholarly journals The interaction ofTrypanosoma congolensewith endothelial cells

Parasitology ◽  
1994 ◽  
Vol 109 (5) ◽  
pp. 631-641 ◽  
Author(s):  
A. Hemphill ◽  
I. Frame ◽  
C. A. Ross
Keyword(s):  
Endothelial Cells ◽  
Binding Assay ◽  
Light And Electron Microscopy ◽  
Trypanosoma Congolense ◽  
Metabolic Energy ◽  
Metabolic Inhibitors ◽  
Feeder Cells ◽  
Cell Plasma Membrane ◽  
Cell Plasma

Factors which affect adhesion of culturedTrypanosoma congolensebloodstream forms to mammalian feeder cells have been examined. Using anin vitrobinding assay, the initial events following interaction of trypanosomes with bovine aorta endothelial (BAE) cells were monitored by both light- and electron microscopy. Metabolic inhibitors and other biochemicals were incubated with either cells or parasites, to test whether any inhibited the process. Our findings suggest that adhesion of the parasites is an active process requiring metabolic energy from the trypanosomes, but not from endothelial cells. We also provide data suggesting thatT. congolensebloodstream forms possess a lectin-like domain, localized at distinct sites on their flagellar surface, which interacts with specific carbohydrate receptors, most likely sialic acid residues, on the endothelial cell plasma membrane. We also suggest that the cytoskeletal protein actin is probably involved in this interaction.

Meiotic maturation of mouse oocytes in vitro: inhibition of maturation at specific stages of nuclear progression

1976 ◽  
Vol 22 (3) ◽  
pp. 531-545
Author(s):  
P.M. Wassarman ◽  
W.J. Josefowicz ◽  
G.E. Letourneau
Keyword(s):  
Cyclic Amp ◽  
Cytochalasin B ◽  
Polar Body ◽  
Germinal Vesicle ◽  
Meiotic Maturation ◽  
Dibutyryl Cyclic Amp ◽  
Germinal Vesicle Breakdown ◽  
Mouse Oocytes ◽  
First Polar Body

In vitro studies of meiotic maturation of mouse oocytes have been carried out in the presence of several drugs. The individual steps of nuclear progression, including dissolution of the nuclear (germinal vesicle) membrane, condensation of dictyate chromatin into compact bivalents, formation of the first metaphase spindle, and extrusion of the first polar body, are each susceptible to one or more of these drugs. Germinal vesicle breakdown, the initial morphological feature characteristic of meiotic maturation, is inhibited by dibutyryl cyclic AMP. However, even in the presence of dibutyryl cyclic AMP, the nuclear membrane becomes extremely convoluted and condensation of chromatin is initiated but aborts at a stage short of compact bivalents. Germinal vesicle breakdown and chromatin condensation take place in an apparently normal manner in the presence of puromycin, Colcemid, or cytochalasin B. Nuclear progression is blocked at the circular bivalent stage when oocytes are cultured continuously in the presence of puromycin or Colcemid, whereas oocytes cultured in the presence of cytochalasin B proceed to the first meiotic metaphase, form an apparently normal spindle, and arrest. Emission of a polar body is inhibited by all of these drugs. The inhibitory effects of these drugs on meiotic maturation are reversible to varying degrees dependent upon the duration of exposure to the drug and upon the nature of the drug. These studies suggest that dissolution of the mouse oocyte's germinal vesicle and condensation of chromatin are not dependent upon concomitant protein synthesis or upon microtubules. On the other hand, the complete condensation of chromatin into compact bivalents apparently requires breakdown of the germinal vesicle. Failure of homologous chromosomes to separate after normal alignment on the meiotic spindle in the presence of cytochalasin B suggest that microfilaments may be involved in nuclear progression at this stage of maturation. Cytokinesis, in the form of polar body formation, is blocked when any one of the earlier events of maturation fails to take place.

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