PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Isotonic Solutions”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed1977

Preparation of uniform haemoglobin free human erythrocyte ghosts in isotonic solution.

A method is described for the preparation of haemoglobin free human erythrocyte ghosts in isotonic solutions using dielectric breakdown technique. In this single haemolytic procedure, almost complete removal of haemoglobin (less than or equal to 0.1%) was achieved by subjecting the erythrocytes suspended in phosphate buffered, isotonic KCl solution at 0 degrees C to three consecutive electrical field pulses of 16 kV/cm in the presence of 10 mM EDTA; EDTA was used to prevent electrical haemolysis. Haemolysis is induced by subsequent dilution with isotonic and isoionic solution to lower the EDTA concentration. Haemolysis is complete after 5 min; the cells are centrifuged, washed and resuspended in a solution of the same composition and osmolarity containing 4 mM MgCl2, but no EDTA. The resealing process, carried out at 37 degrees C, was complete in about 1 h. Measurements of the size distribution of the ghost cells in the hydrodynamically focusing Coulter Counter at varying field strengths in the orifice revealed that the ghost population is nearly uniform. The mean (modal) volume of the ghost cells was 110--120 micronm3 when suspended in phosphate buffered NaCl solution. The apparent breakdown voltage was about 1.3 V.

Erythrocyte Membrane↗
PubMedDate not supplied

Preparation of human erythrocyte ghosts in isotonic solution: haemoglobin content and polypeptide composition.

Human red blood cell ghosts were prepared by dielectric breakdown of the cell membrane and subsequent electrical haemolysis in isotonic and isoionic solutions. Almost complete removal of haemoglobin (to about 0.1%) could be achieved by subjecting the erythrocytes suspended in isotonic solution to three consecutive electric field pulses of 16 kV/cm in the presence of 10 mM EDTA, followed by dilution with EDTA-free isoionic medium. The cup-shaped ghost cells were electrically homogeneous. The polypeptide composition of the electrically prepared ghost cells, as analyzed by polyacrylamide electrophoresis in 1% SDS, revealed a pattern similar to ghost cells prepared by osmotic haemolysis. However, the band 6, corresponding to glyceraldehyde-3-phosphate-dehydrogenase protomer, was absent from the electrically prepared ghost cells. Also the band 8, which is eluted at low ionic strength, appeared to be very prominent in the electrical preparations.

Cell Fractionation↗
PubMedDate not supplied

[Dynamics of inhibition of the hypophyso-adrenal function in the administration of isotonic solutions of hydrocortisone into various hypothalamic nuclei].

Injection of 1% hydrocortisone solution into the arcuate, ventromedial or supraoptic nucleus of the hypothalamus inhibited the activity of the hypophysis-adrenal system. This inhibition began 0.5 hours after the administration of the hormone into the microcellular nuclei and reached the maximum in 2 hours when the corticosteroid secretion was cut by about half. After the injection of hydrocortisone into the supraoptic nucleus inhibition of the hypophysis-adrenal system began later than in its administration into the arcuate or the ventromedial nucleus. In this case the level of corticosteroids began to decrease two hours after the injection, and in 3 hours it was half of the initial one. Apparently hydrocortisone retarded the synthesis of the corticotropine-releasing factor in the hypothalamic nuclei.

Animals↗
PubMed1975

Duodenal control of gastric emptying in the milk-fed calf.

1. It has been ascertained experimentally that an open duodenal cannula does not cause any marked variation in emptying of the abomasum when compared to the rate of emptying of the normal viscus or when the cannulae are closed. 2. Duodenal re-entrant cannulae provide a preparation whereby it is possible to infuse the duodenum via the distal cannula and to collect simultaneously the effluent fluid of the abomasum from the proximal arm of the cannula (Fig. 1). 3. With this preparation the duodenal infusate is not contaminated by the gastric effluent and thus the duodenal stimulus can be restricted to the single non-varying effect of the infusate. 4. In the milk-fed calf using this preparation the following facts have been established. (a) On infusion into the duodenum, hypotonic and isotonic solutions of sodium chloride and sodium bicarbonate increase abomasal emptying; bicarbonate being the more effective stimulus. (b) Potassium chloride, calcium chloride, glucose and hydrochloric acid inhibit gastric emptying when infused into the duodenum. (c) Ammonium chloride, urea, lactose and acetic acid have little effect. (d) Hypertonic solutions of all substances tested were inhibitory to gastric emptying when infused into the duodenum. 5. It has been demonstrated unequivocally that it is the effect of the infusate in the duodenum which controls gastric emptying for when the stomach is isolated from the duodenum, gastric emptying can be manipulated from the duodenum whatever the stomach contents may be. 6. Our results bring firm experimental confirmation of the views discussed by Hunt & Knox (1968) that gastric outflow is regulated by mechanisms initiated from receptors situated in the duodenum.

Abomasum↗
PubMed1978

Tissue osmolality in intestinal villi during luminal perfusion with isotonic electrolyte solutions.

A cryoscoptic technique has been developed that makes it possible to determine tissue osmolality in the core of the intestinal villi. During absorption from an isotonic electrolyte solution containing glucose an osmolality gradient was demonstrated from tip to base of the villi in both the jejunum and the ileum. The tissue osmolality at the villous tips was measured to 1 000-1 200 mOsm/kg H2O while the osmolality at the villous base was approximately isotonic with plasma. Increasing intestinal blood flow by i.a. administration of a vasodilator drug, or making the intestine ischemic by clamping the intestinal vascular supply while supplying the mucosa with oxygen, markedly decreased tissue osmolality. Substituting all sodium ions with choline in the luminal perfusate abolished almost completely the tissue hyperosmolality and the intestine became a secretory organ. These observations are consistent with the view that the observed villous tissue hyperosmolality was created by a countercurrent multiplication of sodium chloride. The physiological implications of this mechanism is discussed and it is, among other things, proposed that the hyperosmolar region represents the hyperosmotic compartment necessary for explaining intestinal water absorption.

Animals↗
PubMed1976

Cell wall development of Micrasterias americana, especially in isotonic and hypertonic solutions.

The cell wall development of Micrasterias americana was investigated by light and electron microscopy. From digestion experiments with pectinase and cellulase, and from fluorescence spectra in Calcofluor and Coriphosphin solution, it was concluded that pectin substances were the main component of the young developing cell wall and that cellulose was synthesized after the daughter hemicell was well developed. In 0-16 M mannitol, wall materials accumulated and were incompletely incorporated into the wall at the region where wall growth would be expected. The plasma membrane was in close contact with the cell wall at the sinus, and this contact was assumed to prevent penetration of wall material at this region, resulting in the accumulation of wall material at regions other than the sinus. The cellulosic wall layer was formed after the production of pectic substances in the 0-16 M mannitol. In 0-3 M mannitol neither a definite wall layer of cellulose nor a pectic wall was produced, presumably due to extensive dilution of the wall materials in the plasmolysed space between the cell wall and the plasma membrane. Under normal circumstances, the shape of the daughter cell is assumed to be determined by the shape of the developed primary wall, which is induced by precocious differentiation of the wall at the sinus.

Cell Membrane↗
PubMed1992

The location of the receptors involved in the human diuretic response to drinking an isotonic electrolyte solution.

1. This study aimed to shed light on the receptors involved in the diuretic response to drinking isotonic fluids in man by employing a polyethylene glycol-based bowel lavage solution (Golytely) which is reported to cause no net movement of fluid across the gut. 2. Drinking Golytely resulted in a transient hypotonic diuresis. Mean urine flow rose from control values of 0.9 ml min-1 to 10.1 ml min-1 70 min after the start of drinking. The increase in urine output was accompanied by a fall in urine osmolality from control values of 879 mosM kg-1 to 105 mosM kg-1. The diuresis is similar to that produced by ingestion of an equal volume of an absorbable electrolyte-based solution (Tyrode). 3. Neither solution produced changes in plasma osmolality or electrolytes, but Golytely provoked a 6.8% contraction of plasma volume, whereas drinking Tyrode resulted in plasma expansion. Copious diarrhoea was experienced by all subjects who drank Golytely solution and by none on drinking Tyrode solution. 4. The infusion of Golytely into the stomach resulted in a hypotonic diuresis similar in magnitude to that elicited by drinking. Drinking with simultaneous aspiration of gastric contents ('sham-drinking') did not produce a significant diuresis. 5. Plasma arginine vasopressin (AVP) levels did not fall following the drinking of Golytely. The assay used was sufficiently sensitive to measure changes of 0.6 pg AVP (ml plasma)-1. 6. The findings show that signals from the oropharynx do not mediate the diuretic response to drinking Golytely in man and that a mechanism other than inhibition of AVP release appears to be involved. The receptors mediating this response may lie in the stomach and/or small bowel since Golytely is not absorbed, as evidenced by the contraction of plasma volume and diarrhoea.

Adult↗
PubMed1992

Effect of hypertonic and isotonic saline solutions on plasma constituents of conscious horses.

Blood constituents and vascular volume indices were determined in 5 standing horses by use of 2-period crossover experimental design. Horses were either administered hypertonic (2,400 mosm/kg of body weight, i.v.) or isotonic (300 mosm/kg, i.v.) saline solution. Each solution was administered at a dosage of 5 ml/kg (infusion rate, 80 ml/min). Samples for determination of PCV, plasma volume, blood volume, plasma osmolality, total amount of plasma protein and plasma concentrations of protein, Na, K, and Cl were collected at 0 hour (baseline, before fluid infusion) and 0.5 hour (at the end of fluid infusion), and subsequently, at 0.25- or 0.5-hour intervals for 4.5 hours. All horses were given the predetermined dose of fluids by 0.5 hour after beginning the saline infusion. Values of P < or = 0.05 were considered significant. Administration of hypertonic saline solution was associated with decreased mean body weight by 4.5 hours, but weight change after isotonic saline administration was not significant. Other than body weight and plasma protein concentration, between-trial difference (treatment effect) was not observed for any measured variable or index. The F values indicated that increasing the number of horses would have not changed these results. A time effect was evident across both trials, so that mean (+/- SD) plasma volume increased (12.3 +/- 1.07%) and mean plasma protein concentration (-12.1 +/- 1.03%) and PCV (-11.9 + 0.67%) decreased proportionately and transiently in association with administration of either fluid at that volume. Other time effects included increased plasma osmolality and Na and Cl concentrations. Blood volume estimates and total amount of plasma protein remained unchanged.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1977

Benzalkonium chloride toxicity to the human cornea.

A 36-year-old woman fitted with a soft contact lens after an uneventful extracapsular cataract extraction was wearing her aphakic lens successfully until she switched her lens-soaking solution to an isotonic solution of boric acid, potassium chloride, and sodium carbonate preserved with benzalkonium chloride and edetic acid. After three days her eye became inflamed and vision decreased. No endothelial damage was apparent and the anterior chamber showed 2+ cell and flare reaction. Three weeks after removal of the lens and fitting with an aphakic lens visual acuity was 6/9 (20/30). Study of the preservative by a semiquantitative dilution method together with the clinical evidence in this case proved the cytotoxic effect of benzolkonium chloride when used to sterilize soft contact lenses.

Adult↗
PubMed1992

Bidirectional peritoneal transport of immunoglobulin in rats: tissue concentration profiles.

Protein transport occurs between the blood and the peritoneal cavity during clinical procedures, but events within the surrounding tissue space are poorly understood. We used quantitative autoradiography to examine the tissue concentration profiles of immunoglobulin G (IgG) in regions surrounding the peritoneal cavity. We have varied the route of administration (intravenous or intraperitoneal), the osmolality of the dialysis solution (isotonic or hypertonic), and the time of analysis (20 or 200 min). After intravenous injection, IgG profiles were relatively flat in most tissues and were not affected by time or osmolality. Concentrations corresponded to the capillary density in specific tissues. After intraperitoneal administration, the IgG tissue profiles were significantly steeper than after intravenous administration. The tissue concentrations increased with time but decreased when a hypertonic solution was substituted for an isotonic solution. Hypertonic dialysis causes a water flux into the cavity, which dilutes the contents but does not prevent penetration of protein into the surrounding tissue. Based on IgG movement in tissue during hypertonic dialysis, the peritoneum appears to function as a heterogeneous structure, which allows osmotically induced water transport into the cavity in some regions with simultaneous transport of hydrostatic pressure-driven water and solute flow from the cavity into the tissue in other regions.

Animals↗
PubMedDate not supplied

Comparative sorption of clomipramine, viloxazine, and maprotiline hydrochlorides in polyvinylchloride bags and glass vials.

The sorption of clomipramine, viloxazine, and maprotiline hydrochlorides was studied comparatively in polyvinylchloride (PVC) bags and glass flasks for up to 72 hours. When stored in glass flasks, no decrease in concentration was observed for any of the three drugs, either in dextrose or sodium chloride isotonic solution. When stored in PVC bags, a slight loss (about 7% within 72 hours), was noted for clomipramine hydrochloride in both isotonic solutions, but not for the other two drugs.

Clomipramine↗
PubMed1992

Effects of verapamil on histamine-induced changes in lung mechanics.

The effects of verapamil on airway resistance and total thoracic compliance were studied in 15 rabbits with histamine-induced changes in lung mechanics. The animals, after being tracheotomized under anaesthesia, were subjected to mechanical ventilation in a time-cycled, volume-limited mode. Airway pressure and gas flow signals measured by a pneumotachograph and integrated for volume, were registered on a recorder. Each animal was given histamine hydrochloride in an isotonic solution of sodium chloride at a rate of 0.05 micrograms.kg-1.min-1 through a peripheral venous line. Verapamil was infused intravenously in an isotonic solution of sodium chloride at a rate of 20 micrograms.kg-1.min-1 after the initiation of histamine. Verapamil reduced the histamine-induced increase in airway resistance by 20% at 20 min after the start of administration.

Airway Resistance↗
PubMed1978

The selection of a stable rat hepatoma variant with concomitant increase in ploidy and permeability to glycerol.

By repeated selection for longer survival in an isotonic solution of glycerol, a stable subline of Novikoff rat hepatoma cells has been isolated. The cells exhibit markedly increased resistances to osmotic lysis in isotonic solutions of glycerol. They are twice as large and have twice as many chromosomes as cells of the parental line. It is suggested that the osmotic stress procedure can be extended for the selection of numerous kinds of mutants and can be used as a method of analysis of membrane properties.

Animals↗
PubMed1976

Peritoneal dialysis in hypernatraemic, ketoacidotic diabetic coma.

Hypertonic dehydration in a 13-year-old boy with ketoacidotic diabetic coma has been treated successfully with peritoneal dialysis and isotonic fluids. Modes of treatment with either hypotonic or isotonic fluids are discussed, as is the feasibility of peritoneal dialysis. We recommend isotonic solutions composed of equal parts of 5.5% glucose and 0.9% sodium chloride combined with peritoneal dialysis in order to secure a relatively slow correction of the hypertonic state.

Adolescent↗