Abstract 23: Body Fluid And Sodium Loss Leads To Aldosterone Hypersecretion And Muscle Catabolism In Hepatocellular Carcinoma Rats.

Hypertension ◽  
2021 ◽  
Vol 78 (Suppl_1) ◽  
Author(s):  
Satoshi Kidoguchi ◽  
Kento Kitada ◽  
Daisuke Nakano ◽  
Takashi Yokoo ◽  
Akira Nishiyama

Background: The number of cancer survivors coincides with cardiovascular diseases is increasing, therefore, we are promoting the concept of “Onco-Hypertension” to clarify the mechanism linking cancer and blood pressure. In this study, we evaluated body osmolyte and water imbalance in hepatocellular cancer (HCC) model rats. Methods: Wistar rats were administered diethylnitrosamine (DEN) (1.5 μg/day, p.o.), a carcinogenic drug, for 8 weeks to establish liver cancer. Three weeks after the completion of DEN administration, we investigated blood pressure, tissue osmolyte and water content, and its association with aldosterone secretion. Results: HCC rats significantly reduced blood pressure, skin sodium, potassium, and water content. In the carcass (muscle + bone), dry weight, sodium, potassium, and water content were dramatically reduced without changing bone mass in HCC rats, suggesting that HCC causes muscle wasting to supply osmolyte and water for the dehydrated organs. These osmolytes and water loss were significantly associated with increased urinary aldosterone excretion. Supplementation of 0.25% salt water to drink improved body sodium and water loss and muscle wasting in HCC rats, which were completely suppressed by treatment with spironolactone (75 mg/kg/day, p.o.), a mineralocorticoid receptor (MR) blocker. Conclusion: These findings suggest that HCC causes body osmolyte and water loss, which leads to aldosterone hypersecretion and muscle catabolism to compensate for dehydration. A relatively small amount of salt supplement ameliorates the HCC-induced dehydration and muscle wasting via aldosterone/MR-mediated sodium and water restoration.

1971 ◽  
Vol 55 (2) ◽  
pp. 345-355
Author(s):  
D. W. SUTCLIFFE

1. The water content, and the concentrations of sodium potassium and chloride in the blood and body water were determined in Gammarus pulex acclimatized to external salinities ranging from 0.06 mM/l NaCl up to 50 % sea water. 2. The mean body water content remained constant at 79.0-80.3 % body wet weight. The total body sodium and chloride concentrations were lowered in 0.06 mM/l NaCl and increased markedly at salinities above 10% sea water. The normal ratio of body sodium/chloride was 1.45-1.70, decreasing to 1.0 at 50% sea water. 3. The total body potassium concentration remained constant at 47.5-55.2 mM/kg body H2O. The rate of potassium loss across the body surface was relatively fast. Potassium balance was maintained at an external potassium concentration of 0.005 mM/l by starved animals, and at 0.005 mM/l by fed animals. 4. The proportion of body water in the blood space was calculated from the concentrations of potassium and chloride in the blood and in the body water. The blood space contained 38-42% body H2O in animals from fresh water. The blood space decreased to 31 % body H2O in animals from 0.06 mM/l NaCl. The sodium space was equivalent to about 70 % body H2O. 5. The mean intracellular concentrations of sodium, potassium and chloride were estimated and the results were compared with previous analyses made on the tissues of G. pulex and other crustaceans. It was concluded that in G. pulex from fresh water the distribution of potassium and chloride ions between the extracellular blood space and the intracellular space approximately conforms to a Donnan equilibrium. 30-40% of the body sodium is apparently located in the intracellular space.


1965 ◽  
Vol 43 (2) ◽  
pp. 257-269
Author(s):  
PAUL W. WINSTON ◽  
V. EUGENE NELSON

1. Groups of sixteen mites were starved for 48 hr. at 29% R.H. and then exposed for 18 or 24 hr. to one of nine humidities, from 0% to 93% R.H. They were weighed as groups before and after the treatments to determine total weight loss. Dry weights were also obtained to find water content and for the calculation of water and dry-weight losses. All work was done at 25° C. 2. Water loss, considered equivalent to total weight loss, was also obtained under several other conditions; and at all humidities it was found to be highest in mites killed in chloroform vapour while it was considerably less in those killed in HCN gas. Mites with spiracles kept open by air with 10% CO2 lost weight at rates midway between those for dead and those for living animals. 3. There is apparent regulation of body-water content as a percentage of the final weight over the whole humidity range. 4. Water loss is restricted by a CO2-sensitive mechanism, presumably the spiracles. 5. Active regulation of water loss by a cuticular mechanim was shown between 53% and 85% R.H., while at humidities below this, loss was actively restricted but not regulated. 6. It is postulated that both restriction and regulation are brought about by the same mechanism, which might be a form of active transport. 7. Uptake of water from unsaturated air was not found with any of the methods used. 8. Regulation such as was found here would help to maintain the internal environment of these mites as nearly constant as possible in the face of fluctuating humidities.


HortScience ◽  
2017 ◽  
Vol 52 (2) ◽  
pp. 320-325 ◽  
Author(s):  
Whitney N. Griffin ◽  
Steven M. Cohan ◽  
John D. Lea-Cox ◽  
Andrew G. Ristvey

Phedimus kamtschaticus (Fischer) were grown in three experimental crushed brick-based green roof substrates (GRSs) with increasing organic matter (OM) content (10%, 20%, and 40% by volume) and a commercially available blend, Rooflite®, in single-pot replicates in a growth chamber for 6 months. Three unplanted replicates of each substrate were included in the design and received identical irrigation volumes as planted replicates. Three destructive harvests indicated that increased substrate OM increased plant root and shoot biomass; however, plants grown in Rooflite® demonstrated greater succulence in the second and third destructive harvests despite similar substrate OM content. By the end of the growth study, there was no difference in dry weight accumulation between the Rooflite® and 40% OM treatment despite the difference in succulence between the two treatments. Substrate volumetric water content (VWC) ranged from 22.5% to below 5% during three consecutive periods of imposed water stress with no differences in evapotranspiration (ET), indicating plants were accessing substrate water previously assumed to be unavailable. Cumulative water loss (normalized for plant dry weight) indicated a likely shift into crassulacean acid metabolism (CAM) around 60-hour postirrigation. Planted treatments (n = 6) lost more water cumulatively (P < 0.05) compared with the unplanted controls (n = 3), although there were no differences in total water loss between substrate treatments.


Author(s):  
Songquan Sun ◽  
Richard D. Leapman

Analyses of ultrathin cryosections are generally performed after freeze-drying because the presence of water renders the specimens highly susceptible to radiation damage. The water content of a subcellular compartment is an important quantity that must be known, for example, to convert the dry weight concentrations of ions to the physiologically more relevant molar concentrations. Water content can be determined indirectly from dark-field mass measurements provided that there is no differential shrinkage between compartments and that there exists a suitable internal standard. The potential advantage of a more direct method for measuring water has led us to explore the use of electron energy loss spectroscopy (EELS) for characterizing biological specimens in their frozen hydrated state.We have obtained preliminary EELS measurements from pure amorphous ice and from cryosectioned frozen protein solutions. The specimens were cryotransfered into a VG-HB501 field-emission STEM equipped with a 666 Gatan parallel-detection spectrometer and analyzed at approximately −160 C.


Author(s):  
R.D. Leapman ◽  
S.Q. Sun ◽  
S-L. Shi ◽  
R.A. Buchanan ◽  
S.B. Andrews

Recent advances in rapid-freezing and cryosectioning techniques coupled with use of the quantitative signals available in the scanning transmission electron microscope (STEM) can provide us with new methods for determining the water distributions of subcellular compartments. The water content is an important physiological quantity that reflects how fluid and electrolytes are regulated in the cell; it is also required to convert dry weight concentrations of ions obtained from x-ray microanalysis into the more relevant molar ionic concentrations. Here we compare the information about water concentrations from both elastic (annular dark-field) and inelastic (electron energy loss) scattering measurements.In order to utilize the elastic signal it is first necessary to increase contrast by removing the water from the cryosection. After dehydration the tissue can be digitally imaged under low-dose conditions, in the same way that STEM mass mapping of macromolecules is performed. The resulting pixel intensities are then converted into dry mass fractions by using an internal standard, e.g., the mean intensity of the whole image may be taken as representative of the bulk water content of the tissue.


2005 ◽  
Vol 37 (5) ◽  
pp. 425-432 ◽  
Author(s):  
Ana PINTADO ◽  
Leopoldo G. SANCHO ◽  
T. G. Allan GREEN ◽  
José Manuel BLANQUER ◽  
Roberto LÁZARO

The Tabernas badlands in semiarid south-east Spain is one of the driest regions in Europe with a mean annual precipitation of c. 240 mm. The landscape is deeply dissected, with canyons, ramblas and sparsely vegetated eroded badland slopes. The vegetation is predominantly a biological soil crust consisting of different types of lichen-rich communities, one of the more conspicuous being dominated by Diploschistes diacapsis (Ach.) Lumbsch. This lichen is mainly restricted to the north- facing slopes, where it forms extensive whitish carpets and probably plays an important role in preventing erosion of the slopes and allowing plant colonization. South-facing slopes are much more eroded and generally lack vegetation. %The photosynthetic performance of north (shade) and south-facing (sun) populations of D. diacapsis was studied to determine if these different populations showed any adaptations to the microclimatic conditions of their individual habitats. The response of CO2 exchange to light intensity, temperature and water content was measured under controlled conditions in the laboratory. Dry weight-based net photosynthetic rates were higher in the southern-exposed population but quantum efficiency, and light compensation points were similar. Thallus weight per unit area (LMA) was considerably higher for shade specimens but maximum water content and optimal water content were very similar and chlorophyll content on a dry weight basis was also similar. Chlorophyll content on an area basis was higher in the northern-exposed population and always much larger than those reported in other studies on the same species (up to 8 times larger) with the result that NP values on a chlorophyll basis were relatively low. The larger LMA meant that shade thalli stored more water per unit area which should ensure longer active periods than sun thalli. The results support a strategy pair of high NP and short active time versus low NP and long active time, both having been reported for other soil crust species. However, the visibly larger biomass of the shade D. diacapsis suggests that the lichen is at the limit of its adaptability in these habitats.


2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
C Delgado ◽  
M Delgado-Lelievre ◽  
D Lelievre ◽  
A Delgado-Almeida

Abstract Introduction The sodium voltage-gated channel alpha subunit 7 (SCN7A) has been associated to renal Na regulation and hypertension. This study explores the relationship between blood pressure (BP) and urinary overnight Na/K ratio (UONaK) in hypertensives (HT) and normotensive (NT) subjects from from National Heart, Lung and Blood Institute funded, Family Blood Pressure Program (FBPP) that were genotyped for 3 SNPs for SCN7A: CV2161217, CV 356958 and CV433036. Hypothesis Genetic variations in the SCNA7 are differently associated to BP and UONaK in HT and NT. Methods 1,749 subjects genotyped for SCN7A SNPs CV2161217, CV 356958 and CV433036 were analyzed from FBPP. Subjects with diastolic BP (DBP) ≥80 or systolic BP (SBP) ≥130 mmHg were classified HTN; subjects with SBP &lt;130 and DBP &lt;80 mmHg were classified as NT. UONAK was calculated by dividing overnight Na by K concentration. Correlation analysis done with partial variables (use of antihypertensive drug, use of diuretics, overnight urine creatinine). Results For the CV2161217, HTN group (n=1,030), 52% had C/C, 39% C/T and 9% T/T. In NT group (n=719), 52% had C/C, 38% C/T and 10% T/T. In the HT group, subjects with CC genotype showed strong correlation between DBP and UONaK (Fig 1a) while no significant correlation with SBP. Those with CT genotype maintained the correlation between SBP and UONaK (r=0.10, p=0.03) with no correlation with SBP. The TT showed no correlation between UONaK and SBP or DBP. In the NT, subjects with TT genotype showed strong correlation between DBP and UONaK (Fig 1b) and with SB (r=0.256, p=0.03). Those with CT or TT genotypes showed no correlation between UONaK and SBP or DBP. Similar finding were obtained for CV356958 SNP; no similar association was observed in the CV433036 SNP. Conclusions Subjects with the genetic variations in the SCNA7, such as CV2161217 and CV 356958 SNPs, showed significant correlation between blood pressure and overnight urinary sodium potassium. This finding could have important implications in non dipping status observed in some hypertensive patients. Funding Acknowledgement Type of funding source: None


1968 ◽  
Vol 14 (9) ◽  
pp. 859-870 ◽  
Author(s):  
Harold Dahms ◽  
Robert Rock ◽  
David Seligson

Abstract Ionic activities of sodium, potassium, and chloride in serums of 26 hospitalized patients were determined with ion-specific electrodes. Comparison of the activities with the corresponding concentrations shows that the two most important parameters influencing the molar activity coefficients of these ions are the water content of serum and the binding between albumin and chloride. Quantitative expressions for activity-concentration conversion factors are given. Calculations show that the conversion factors vary significantly in disease states due to changes in protein.


1944 ◽  
Vol 35 (2) ◽  
pp. 127-139 ◽  
Author(s):  
G. Fraenkel ◽  
M. Blewett

(1) Three insects,Tribolium confusum, Ephestia kuehniellaandDermestes vulpinus, have been grown at several humidities and the following factors have been determined: length of larval period; water content of food and of the freshly formed pupae; wet and dry weight of pupae and wet and dry weight of food consumed during larval development. The “net utilisation” of the food has been calculated as the ratio of dry weight of food eaten per larva to dry weight of pupa.(2) At lower humidities more food is eaten to produce a given unit of body weight. The length of the larval period increases and the weight of the pupae decreases.(3) More food is eaten at low humidities, because part of the food is utilised as water. As a consequence of this, the larva grows more slowly and its final size is smaller. It is shown forDermestesat 30 per cent. andEphestiaat 1 per cent. R.H. that less than 32·9 and 7·6 per cent. of the water in the pupae can be derived from water ingested with the food.


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