Cell volume regulation in isolated,perfused heart ventricle of the flounder (Platichthys flesus)

• 1.1. The ventricle cells of the flounder (Platichthys flesus) maintained the cell volume regulation mechanism in vitro, when isolated hearts were submitted to a hyposmotic solution.
• 2.2. The initial osmotic swelling of the cells was followed by a secondary shrinking. A new steady state volume (water content) was established in the course of 6 hr. The water content was 3% above control.
• 3.3. The cellular amount of K⁺ and taurine decreased concomitantly with the decline in cellular water.
• 4.4. The decrement in cellular taurine was explained by leakage of taurine, per se, into the perfusion media.

     

Contrast in adenine uptake by chicken and rabbit erythrocytes in vitro

• 1.1. Relative to rabbit erythrocytes, chicken red blood cells exhibit a much greater capacity to utilize [³H]adenine for nucleotide synthesis in vitro, even at 5°C and in the absence of added inorganic phosphate.
• 2.2. This difference is largely due to a higher concentration of phosphoribosylpyrophosphate and greater activity of adenine phosphoribosyltransferase in the avian cells. lli]3. The capacity of avian erythrocytes for utilization of guanine and hypoxanthine is several fold less than that of adenine.
• 3.4. The data are consistent with lower activity for hypoxanthine/guanine phosphoribosyltransferase than for adenine phosphoribosyltransferase in intact chicken erythrocytes.
• 4.5. The results indicate that reutilization of adenine by chicken erythrocytes may be physiologically significant.

     

Isotopic labeling of taurine; implications for its synthesis in selected tissues of Homarus americanus

• 1.1. The abdominal muscle and ventral nerve chord of Homarus americanus were incubated with radioactive precursors.
• 2.2. ³⁵SO₄ and ¹⁴C-CO₂ were not incorporated into amino acids in the abdominal muscle.
• 3.3. ¹⁴C-glucose was incorporated into serine, cysteine, cysteine-sulfinic acid and taurine in the abdominal muscle.
• 4.4. ¹⁴C-CO₂ appeared to be slightly incorporated into taurine in the ventral nerve chord.
• 5.5. ¹⁴C-glucose incubation with the ventral nerve chord resulted in labeling of the same amino acids as in the abdominal muscle.
• 6.6. The results are discussed in view of the catabolism of carbohydrates and the synthesis of taurine.

     

The effect of reduced salinity on tissue and plasma composition of the dogfish,Squalus acanthias

• 1.1. Dogfish (Squalus acanthias) were acclimated to reduced salinities and their plasma, muscle tissue and erythrocytes subsequently analysed.
• 2.2. Decrease in the osmolarity of the plasma was principally due to a fall in urea concentration and a significant fall in the concentrations of sodium and chloride.
• 3.3. Changes in the muscle and erythrocytes in dilute media were a decrease in urea, potassium, sodium and chloride concentrations.
• 4.4. The concentrations of the free amino acids in the muscle and the red blood cells decreased more than would be expected by the movements of water only.
• 5.5. The results were discussed in relation to the regulation of cellular volume and the involvement of the free amino acid pool of the tissues in this process.

     

Purification and characterization of hatching enzyme of the pike (Esox lucius)

• 1.1. A choriolytic enzyme was isolated from the hatching medium of the pike, Esox lucius.
• 2.2. The enzyme is defined as hatching enzyme.
• 3.3. The molecular weight of the enzyme is 24,000.
• 4.4. The enzyme is a glycoprotein containing 2% carbohydrate.
• 5.5. Its isoelectric point is 6.5.
• 6.6. The pH optimum is around pH 8.
• 7.7. The enzyme molecule contains two disulfide bonds but no free cysteine.
• 8.8. Inhibitor studies and metal analysis show that the enzyme is a zinc-metalloprotease.

     

Haematology of the australian eastern quoll,Dasyurus viverrinus

• 1.1. A variety of haematological parameters were determined in adult Dasyurus viverrinus.
• 2.2. Haemoglobin and red cell counts were high with a very low mean cell volume.
• 3.3. Basophils are absent but the eosinophils contain small numbers of basophilic granules which may indicate a dual role for this cell.
• 4.4. “Ring Form” leucocytes are present.
• 5.5. Three types of red cell picture could be identified, some animals showing large numbers of spherocytes, spicule cells, and inclusion bodies.
• 6.6. These cells resemble those found in some inherited human haemolytic anaemias but there was no evidence of haemolysis in the animals.
• 7.7. An alkali resistant haemoglobin component is present.

     

1H NMR study of metabolic alterations in the small intestine of rats infected with Hymenolepis diminuta

• 1.1. 1H NMR spectra of the duodenum, jejunum and ileum tissues of the small intestine of a rat showed metabolic gradients.
• 2.2. The concentrations of metabolites in these gut regions were altered by the presence of the tapeworm Hymenolepis diminuta.
• 3.3. In the infected duodenum there was significantly less glycogen, glucose and phosphocreatine/creatine, but significantly more lactate than in the corresponding controls.
• 4.4. Infected jejunum contained significantly less betaine but significantly more succinate, alanine and lactate.
• 5.5. Infected ileum had significantly less glycogen and taurine but significantly more alanine and lactate.

     

Permeability of erythrocytes to glycerol and its acylated derivatives in the camel and dog

• 1.1. Glycerol and glyeerol derivatives transport was compared in human, dog and camel erythrocytes.
• 2.2. The camel erythrocytes had the slowest glyeerol transport, that of the dog erythrocytes was also slow, while the quickest transport occurred in human erythrocytes.
• 3.3. In glyeerol mono-, di- and triacetates the transport in camel and dog erythrocytes increased until in the triacetate the quickest transport was found.
• 4.4. Addition of copper ions had no inhibiting effect on glyeerol transport in camel erythrocytes but a striking effect was seen in human erythrocytes.
• 5.5. Changes in pH greatly affected transport in camel erythrocytes, a decline in pH enhanced and an increase in pH slowed the transport. Storage of camel erythrocytes did not affect the glyeerol transport in camel erythrocytes.
• 6.6. It is concluded that the mechanism of glyeerol transport in camel erythrocytes is one of a non-facilitated diffusion.

     

Reduction of ferrihemoglobin in erythrocytes of birds and mammals

• 1.1. Species differences exist in ferrihemoglobin reduction rates in bird and mammalian red cells, bird erythrocytes being very active reducers.
• 2.2. Glucose and lactate enhance ferrihemoglobin reduction. In horse and quail red cells β-hydroxybutyrate has this effect as well.
• 3.3. Malate and pyruvate do not enhance ferrihemoglobin reduction.
• 4.4. Plasma addition to red cell suspensions enhances ferrihemoglobin reduction; addition of lactate mimics this effect in all species except the dog.
• 5.5. Incubation conditions are very important for measuring ferrihemoglobin reduction. Especially the presence of bicarbonate ions is essential. In our experiments no inhibition of reduction rates by chloride ions is found.
• 6.6. Mitochondrial NADH production does not play a role in ferrihemoglobin reduction in bird red cells.

     

Seasonal changes of circulating blood parameters in the grass snake Natrix natrix natrix L.

• 1.1. Seasonal changes of circulating blood parameters of Natrix n. natrix were evident and involved both sexes to the same extent.
• 2.2. A significant decrease in red cell count, haematocrit and haemaglobin concentration in the mating period, and an increase in those parameters and mean cell volume in autumn were observed, and haemodilution during winter torpor.
• 3.3. The changes during the breeding season had probably a hormonal background; in winter, they resulted first of all from a decreased erythropoietic activity and, to a lesser extent, from an increased red blood cell breakdown rate. However, the possibility that some erythrocytes were withdrawn from the circulation cannot be excluded.
• 4.4. Winter lymphocytopenia, eosinocytopenia and neutrophilic granulocytosis in females during egg laying were expressions of changes of leucocyte formula.
• 5.5. Seasonal cyclicity was found only with respect to the white cell count in males and the eosinophile fraction in males and females.
• 6.6. Probable reasons for, and mechanisms of the changes in blood composition are discussed.

     

Short-term osmotic responses of cells and tissues of the sea anemone,Condylactis gigantea

• 1.1. Cells of tentacles and body wall of the sea anemone Condylactis gigantea behaved as simple osmometers during 5hr exposure to 50, 67, 83, 100 and 125% sea-water.
• 2.2. All intracellular water appeared to be osmotically active.
• 3.3. Cell sodium, chloride and total osmolyte content remained invariable, with taurine decreasing and potassium increasing as sea-water concentration was reduced.
• 4.4. Tissues, as a whole, exhibited a pseudoregulatory response to changes in salinity as the large and osmotically inert extracellular space buffered volume changes to a considerable extent.

     

Kinetics of porphyrin accumulation in cultured epithelial cells exposed to ALA

• 1.1. The kinetics of porphyrin accumulation in cultured mammalian epithelial cells (CNCM-I-221) during exposure to ALA was investigated.
• 2.2. The total porphyrin synthesized is a function of ALA concentration and the incubation time. The cellular porphyrin content exhibited a saturation pattern, reaching a plateau at about 0.04 fmol porphyrins/cell. A biphasic time-dependent increase in the total porphyrin synthesized was observed.
• 3.3. After 3 hr of exposure to ALA the rate of synthesis increased to ahnost twice the initial rate, reaching between 0.02 and 0.05 fmol porphyrins/cell/hr depending on serum concentration in the medium.
• 4.4. Two effects of FBS on ALA-stimulated porphyrin accumulation were observed. Greater total porphyrin synthesis was found when incubations were made in 10% FBS compared to those in 1% FBS.
• 5.5. The higher serum concentration also caused a greater release into the medium of the porphyrins generated in the cells with a calculated half-life of 24 min in 10% serum-supplemented medium compared with 62 min in 1% serum.
• 6.6. The results obtained from cell synchronization experiments suggest that there is little obvious cell cycle-dependent variation in the synthesis of porphyrins from ALA.
• 7.7. The small differences in the intracellular porphyrin content that were observed may be attributed to a slight reduction in the rate of loss of porphyrins in G2/M cells.

     

Superoxide dismutase,reduced glutathione and TBA-reactive products in erythrocytes of patients with multiple sclerosis

• 1.1. Superoxide dismutase, reduced glutathione and lipid peroxides levels were determined in the erythrocytes of multiple sclerosis patients.
• 2.2. Superoxide dismutase activity and the malonyldialdehyde production rate were found to be significantly enhanced.
• 3.3. The isoelectric focusing pattern of Superoxide dismutase from multiple sclerosis and normal subjects erythrocytes was substantially overlapping.
• 4.4. Our results indicate the occurrence of a higher susceptibility of multiple sclerosis erythrocytes to lipid peroxidation.

     

Stimulation of plasmin activity in cultured human fibroblast cells by Porphyromonas endodontalis

• 1.1. Plasmin activity in the conditioned medium of Gin-1 cells, a human gingival fibroblast cell line, was stimulated by Porphyromonas endodontalis, a putative pathogen of oral submucous abscesses, in a time- and dose-dependent manner.
• 2.2. P. endodontalis stimulated the activity of plasminogen activator in both the conditioned medium and the cell lysate. The plasminogen activator in Gin-1 cells was approx. 50kDa by zymography.
• 3.3. The conditioned medium of Gin-1 cells exposed to P. endodontalis stimulated the conversion of human serum prekallikrein to kallikrein.
• 4.4. These results suggested that P. endodontalis stimulates the plasminogen activator-plasmin system in Gin-1 cells, and that activated plasmin plays a role in the progress of periodontal tissue inflammation.

     

Effect of polyunsaturated fatty acids on the growth of fish cells in culture

• 1.1. The effects on growth of supplementing the medium with (n-3) and (n-6) polyunsaturated fatty acids (PUFA) were investigated in Atlantic salmon (AS) and turbot (TF) cell lines.
• 2.2. Neither cell line grew in the absence of serum, and addition of increasing percentages of serum resulted in graded increases in cell growth in both cell lines.
• 3.3. The growth of AS cells was stimulated by supplementing the medium with both (n-6)PUFA and (n-3)PUFA at 5–25 μM, especially 18:3(n-3) and 20:5(n-3).
• 4.4. Intermediate concentrations (15–20 μM) of 18:2(n-6) and 18:3(n-3) increased cell growth in TF cells, although only after 8 days in culture.
• 5.5. In contrast, both (n-3) and (n-6)PUFA at 25 μM tended to inhibit the growth of TF cells, and in longer incubations caused cell death.
• 6.6. The inhibition of TF cell growth rate and, in particular, the cell death induced by 25 μM PUFA could be abolished by the addition of vitamin E to the medium.

     

Cell surface labeling by iodine monochloride

• 1.1. Human red cell membranes were trace iodinated with [¹²⁵I]ICI and the distribution of label in membrane components examined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis.
• 2.2. With intact erythrocytes over 84% of the bound iodine was associated with the membrane.
• 3.3. Two membrane components accounted for almost all of the label, band 3 and PAS-1.
• 4.4. Spectrin was not labeled in resealed ghosts.

     

Taurine regulation of Ca2+ uptake and (Ca2+ + Mg2+)-ATPase in developing chick B-cells

• 1.1. The objective of the present study was to determine the effect of age and taurine on chick B cell calcium uptake and membrane (Ca²⁺ + Mg²⁺)-ATPase activity in 1–4-week-old chicks.
• 2.2. The calcium uptake rate decreased with age (P < 0.05) and was further decreased by taurine (P < 0.05).
• 3.3. (Ca²⁺ + Mg²⁺)-ATPase activity increased with age (P < 0.05) and was stimulated by taurine (P < 0.05).
• 4.4. The data demonstrate that the flux of calcium across the B-cell membrane changes during early post-hatch development, and that taurine regulates both the influx and efflux of calcium in chick B-cells.

     

A comparative study of seafish erythrocytes and agglutinins from seaweeds

• 1.1. To date, only a few authors have assayed the agglutinic activity of marine algae against fish erythrocytes, and in these cases, mainly against freshwater fish.
• 2.2. For the first time, the hemagglutinic activity of 70 seaweeds (29 brown, 37 red and four green algae) against erythrocytes of 16 seaflsh species is reported.
• 3.3. The presence of agglutinins was demonstrated in 100% of algae assayed, against at least one of the different types of erythrocytes tested.
• 4.4. The results obtained confirm the presence of receptors for algae agglutinins on the surface of the erythrocytes of the fish studied.
• 5.5. This could be useful in establishing the origins of fish populations, as these serological differences could distinguish between populations of cultivated and wild fish.

     

Effects of dehydration and rehydration on the intravascular space in horses

• 1.1. The resistance of sub-tropical horses, and desert-dwelling horses to 72 hr dehydration/24 hr rehydration was investigated via changes in red cell parameters and plasma protein concentration.
• 2.2. Red cell count, haemoglobin and haematocrit increased up to 48 hr dehydration. Between 48 and 72 hr dehydration these parameters decreased, implying a fluid shift onto the intravascular space from the interstitium/hindgut. Most parameters had regained baseline values by 24 hr rehydration.
• 3.3. Mean cell volume, mean cell haemoglobin, mean cell haemoglobin concentration and total plasma protein were not significantly different between breeds at, or between most stages of hydration.
• 4.4. Protection of plasma volume during dehydration/rehydration was aided by maintaining intravascular protein (especially albumin) levels. Red cells were transiently dehydrated and overhydrated but resisted osmolysis.

     

A fetal-maternal shift in the oxygen equilibrium of hemoglobin from the viviparous caecilian,Typhlonectes compressicauda

• 1. The equilibria and kinetics of oxygen binding by blood and hemoglobin from adult and fetal caecilians,Typhlonectes compressicauda, have been measured.
• 2. The oxygen affinity of fetal blood is higher than that of adult blood.
• 3. Electrophoresis of adult and fetal hemoglobins suggests that they may be identical: a major and minor component occurs in each.
• 4. Adult and fetal hemoglobins have identical oxygen equilibria. Stripped hemoglobins have a high oxygen affinity and no Bohr effect between pH 6.5 and 10.0. An “acid”, reversed Bohr effect is present below pH 6.5. The addition of 1 mM ATP reduces the oxygen affinity markedly and produces a moderate, normal Bohr effect.
• 5. The major nucleoside triphosphate in fetal and adult erythrocytes is adenosine triphosphate: about 10% of the nucleoside triphosphates is guanosine triphosphate. Adult erythrocytes contain 3 times as much ATP as do the fetal erythrocytes.
• 6. The fetal to maternal shift in the oxygen equilibrium is mediated entirely by the difference in ATP content of the maternal and fetal red blood cells.