Determination of extracellular fluid volume in the dog with ferrocyanide

Abstract

The suitability of ferocyanide as an indicator for the measurement of extracellular fluid volume was tested. Added ferrocyanide could be recovered completely from urine, plasma and blood. In in vitro experiments ferrocyanide did not penetrate into erythrocytes, nor did it adhere to the red cell membrane. In gel filtration and electrophoresis experiments binding of ferrocyanide to plasma proteins could not be demonstrated. In in vivo experiments on dogs, the urinary recovery of intravenously administered ferrocyanide was 98.9 +/- 2.1% (n = 14). The partition ratio of ferrocyanide between lymph water and plasma water was 0.99 +/- 0.02 (n = 20). Ferrocyanide could not be detected in cerebrospinal fluid or red cells of dogs after administration by intravenous infusion. No untoward effects of the infused ferrocyanide were observed during or after the experiments. In nephrectomized dogs ferrocyanide reached its ultimate distribution volume 2 hrs after intravenous administration of a single dose and remained constant for up to 10 hrs. The average distribution volume was 224 +/- 17 ml-kg-1 body mass (n = 6). In intact dogs continuously infused with indicator, ferrocyanide also reached its ultimate distribution volume in 2 hrs and remained constant thereafter for up to 7 hrs after the start of the infusion. The average distribution volume was 237 +/- 27 ml-kg-1 body mass (n = 14). It is concluded that ferrocyanide fulfils the requirements to be met by an indicator for the measurement of the extracellular volume, and is well suited for repeated determinations of the extracellular fluid volume in one and the same experiment.

Body Fluid Compartment Volumes in Chronically Hypoxemic Lambs

“…The exact amount of indicator injected was determined by weighing the syringe containing the indicator mixture before and after the injection. After treatment of the samples as described below, light absorbances were measured and converted to concentrations by using a calibration line that was determined before each set of measurements as described by Zweens et al (14)(15)(16). The Evans Blue concentration was measured in the samples withdrawn at 20, 30, 40, 50, and 60 min.…”

“…Because ferrocyanide is freely filtered by the glomeruli and neither excreted nor reabsorbed by the tubules, the GFR was calculated from the slope of the monoexponential tail of the disappearance curve (14).…”

Blood volume and body fluid compartments in lambs with aortopulmonary left-to-right shunts.

“…Concentrations of Evans blue, sodium ferrocyanide, and D20 were measured spectrophotometrically as described by Zweens and coworkers (24,26,31 ). Evans blue concentration was determined in the samples that were withdrawn at 20, 30, 40, 50, and 60 min.…”

“…After 10 min the mixture was centrifuged for 10 min at 7,000g. To 4 ml ofthe supernatant was added I ml ofa solution of 5 g/liter FeSO4 and H2SO4 (90 mmol/liter) in H20, prepared at least I wk in advance (31 ). After 25 min a blue color had developed (Prussian blue, Fe[Fe(CN)6f), which remained stable for 2 15 min, during which the absorbance of the solution was measured at 700 nm against a similarly treated plasma blank by means of a grating spectrophotometer (model CF4; Optica, Milan, Italy).…”

Etchable plasmonic nanoparticle probes to image and quantify cellular internalization

“…S5), a feature which could enable pulse-chase experimental formats. 22 Clinical blood chemistry analysis of mice injected with Ag-NA or the etchant showed normal hepatic and kidney function as measured, for example, by analysis of alanine aminotransaminase, amylase, and blood urea nitrogen levels, indicating the general safety of both Ag-NA 23 and etchant 18,32,33 in cell and tumor homing studies (Fig. 2d, Supplementary Fig.…”