Search results for "Isotonic Solutions"

Bohr-effect and buffering capacity of hemocyanin from the tarantula E. californicum.

2003

A previous report showed that binding of oxygen to the 24-meric hemocyanin from E. californicum does not correlate linearly with the release of protons as known from hemoglobin. However, this unusual complex phenomenological observation could not be explained at that time. Here, I present a full analysis of the thermodynamic coupling between protons and oxygen for the 24-meric tarantula hemocyanin in Ringer-solution based on the Nested-MWC-model. A strategy is presented which allows to reduce the number of free parameters when fitting the model to the data by including explicitly the equilibrium constants for binding of protons to the different conformations. The results show that the Neste…

Crystalloids and hydroxyethyl starches in noncardiac surgical patients

2016

Modulatory role of magnesium on the contractile response of rat aorta to several agonists in normal and calcium-free medium.

1993

Abstract Acute withdrawal of external Mg2+ increased basal tone of rat isolated aorta incubated in the presence of Ca2+. Above normal levels of Mg2+ (1–4 Mm) inhibited basal tone while much higher levels of the divalent cation (64–256 Mm) evoked contractile responses regardless of the presence of Ca2+. Contractile responses to noradrenaline (1μm) and KCl (80 Mm) were inhibited by addition of cumulative concentrations of Mg2+. Acetylcholine-induced contractions in the presence of physiological concentrations of Mg2+ (1 Mm) decreased gradually to the basal tone, but a sustained contraction was observed in the absence of this ion. In Ca2+-free medium, acetylcholine-induced phasic responses ind…

Influence of intracellular sodium concentration on calcium influx in isolated guinea pig auricles.

1969

Titrated hypertonic/hyperoncotic solution for hypotensive fluid resuscitation during uncontrolled hemorrhagic shock in rats.

2002

In volume- or pressure-controlled hemorrhagic shock (HS) a bolus intravenous infusion of hypertonic/hyperoncotic solution (HHS) proved beneficial compared to isotonic crystalloid solutions. During uncontrolled HS in animals, however, HHS by bolus increased blood pressure unpredictably, and increased blood loss and mortality. We hypothesized that a titrated i.v. infusion of HHS, compared to titrated lactated Ringer's solution (LR), for hypotensive fluid resuscitation during uncontrolled HS reduces fluid requirement, does not increase blood loss, and improves survival.We used our three-phased uncontrolled HS outcome model in rats. HS phase I began with blood withdrawal of 3 ml/100g over 15 mi…

Gef��- und Tubulusweite der Niere bei osmotischer und Wasserdiurese und nach Theophyllininjektionen

1960

The effects of i.v. administered hypertonic solutions (6-fold isotonic solutions of NaCl, sodium sulfate, glucose and mannitol) theophylline (25 mg/kg) and vasopressin (50 mE/kg) on the blood pressure, cortical kidney vessel blood content and tubulus dilatation were studied in large groups of mice. The blood pressure and blood content effects after i.p. injection of 10% NaCl solution and the blood content during water diuresis were also investigated. The kidney vessel blood content was determined through benzidine stained erythrocytes in kidney slices. An increase in blood content as compared to corresponding controls was consistently noted after i.v. injection of 6-fold isotonic solutions …

Innovative barriers for peritoneal adhesion prevention: liquid or solid? A rat uterine horn model.

2005

Objective To compare the effects of solid barriers (PDLA membrane and foil, Interceed), innovative barrier solutions (Adept and Hyalobarrier Gel, phospholipid emulsion), and Ringer’s lactate solution in preventing postsurgical peritoneal adhesions in the rat. Design Prospective, randomized experimental study. Setting Rat model in an academic research environment. Animal(s) Female, nonpregnant Wistar rats. Intervention(s) Standardized surgical injuries were applied to the parietal and visceral peritoneum and the uterine horns. The barrier agents were applied and the wound was closed. A second-look laparoscopy was performed 31 days after surgery to assess adhesion formation. Main Outcome Meas…

The influence of Ca2+ antagonists on the ciliary activity of the guinea pig trachea.

1990

The ciliary activity of the guinea pig tracheal respiratory epithelium was measured using a photoelectric device. Fourteen animals were administered 75 mg diltiazem/kg body weight 2 days, 1 day and 4 h prior to the investigation. Thirteen animals served as controls. In the pretreated group, the mean ciliary stroke frequency (13.4 +/- 3.0 Hz) was significantly lower (P = 0.02) than in the control group (16.6 +/- 3.7 Hz). The application of aerosolized 0.3 mmol/l nifedipine solution on the tracheal preparations of the control animals also significantly reduced the stroke frequency (P = 0.02). The ciliary activity never dropped beyond a frequency of about 8 Hz. The most probable interpretation…

The ionic dependence of calcium efflux from guinea pig auricles.

1968

Effect of divalent cations on KCl- and noradrenaline-induced contractile responses in rat aorta after nifedipine treatment.

1999

Abstract Nifedipine (1 μM) relaxed the sustained contractile responses induced by 1 μM noradrenaline or 60 mM KCl in rat aortic strips. After washing, a second addition of the spasmogens gave smaller tonic contractions than the first one. Even more, a third addition of KCl also gave a smaller contraction than the first one, but a complete recovery of the contractile response to noradrenaline was obtained by a third addition of this agonist. Application of cumulative amounts of Ca2+ or Ba2+ (2.4–24 mM) on the residual contraction in response to these agents after nifedipine treatment, but in the absence of the blocker, restored the magnitude of the contractile responses. Addition of cumulati…