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Water plays a vital role in the life cycle of plants, participating in various critical biochemical reactions during both non‐photosynthetic and photosynthetic processes. Direct visualization of the metabolic activities of water in plants with high spatiotemporal resolution is essential to reveal the functional utilization of water. Here, stimulated Raman scattering (SRS) microscopy is applied to monitor the metabolic processes of deuterated water (D2O) in model plant Arabidopsis thaliana (A. thaliana). The work shows that in plants uptaking D2O/water solution, proton‐transfer from water to organic metabolites results in the formation of C‐D bonds in newly synthesized biomolecules (lipid, protein, and polysaccharides, etc.) that allow high‐resolution detection with SRS. Reversible metabolic pathways of oil‐starch conversion between seed germination and seed development processes are verified. Spatial heterogeneity of metabolic activities along the vertical axis of plants (root, stem, and tip meristem), as well as the radial distributions of secondary growth on the horizontal cross‐sections are quantified. Furthermore, metabolic flow of protons from plants to animals is visualized in aphids feeding on A. thaliana. Collectively, SRS microscopy has potential to trace a broad range of matter flows in plants, such as carbon storage and nutrition metabolism. [ABSTRACT FROM AUTHOR]

This study explored whether and how prohexadione calcium (Pro-Ca) regulated wheat tolerance to drought stress (DS). Findings displayed that DS had significant influence on antioxidant metabolism, water balance and the photosynthesis. DS significantly improved the activity level of enzymatic antioxidants superoxide dismutase (SOD), catalase (CAT), peroxidase (POD) and ascorbate peroxidase (APX), the contents of non-enzymatic antioxidants ascorbic acid (AsA) and glutathione (GSH), electrolyte leakage (EL), malondialdehyde (MDA), and the contents of osmotic regulatory substances soluble protein (SP), soluble sugars (SS) and proline (Pro), compared with control. Whereas DS significantly reduced transpiration rate (Tr), stomatal conductance (gs) and relative water content (RWC), photosynthetic pigments chlorophyll and carotenoid contents, net photosynthetic rate (Pn), maximum photochemical efficiency of PSII (Fv/Fm), plant height and biomass. Compared to DS, Pro-Ca plus DS significantly promoted the antioxidant metabolism by improving the activity level of SOD, CAT, POD and APX and increasing AsA and GSH contents, which in turn reduced MDA content and EL. In addition, Pro-Ca plus DS significantly maintained water balance by promoting the accumulation of osmolytes SP, SS and Pro, which in turn increased RWC, Tr and gs. Pro-Ca plus DS also significantly promoted photosynthesis by increasing the contents of the above photosynthetic pigments, Pn and Fv/Fm, thereby promoting plant growth. These findings indicated that Pro-Ca was a potential agent to improve wheat tolerance under water deficit. [ABSTRACT FROM AUTHOR]

Introduction: Blood pressure (BP) regulation is a complex process involving several factors, among which water-sodium balance holds a prominent place. Arginin-vasopressin (AVP), a key player in water metabolism, has been evoked in hypertension development since the 1980s, but, to date, the matter is still controversial. Hyaluronic acid metabolism has been reported to be involved in renal water management, and AVP appears to increase hyaluronidase activity resulting in decreased high-molecular-weight hyaluronan content in the renal interstitium, facilitating water reabsorption in collecting ducts. Hence, our aim was to evaluate urinary hyaluronidase activity in response to an oral water load in hypertensive patients (HT, n=21) compared to normotensive subjects with (NT+, n=36) and without (NT-, n=29) a family history of hypertension, and to study its association with BP and AVP system activation, expressed by serum copeptin levels and urine Aquaporin 2 (AQP2)/creatinine ratio. Methods: Eighty-six Caucasian men were studied. Water load test consisted in oral administration of 15-20 ml of water/kg body weight over 40-45 min. BP, heart rate, serum copeptin, urine hyaluronidase activity and AQP2 were monitored for 4 hours. Results: In response to water drinking, BP raised in all groups with a peak at 20-40 min. Baseline levels of serum copeptin, urinary hyaluronidase activity and AQP2/creatinine ratio were similar among groups and all decreased after water load, reaching their nadir at 120 min and then gradually recovering to baseline values. Significantly, a blunted reduction in serum copeptin, urinary hyaluronidase activity and AQP2/creatinine ratio was observed in NT+ compared to NT-subjects. A strong positive correlation was also found between urinary hyaluronidase activity and AQP2/creatinine ratio, and, although limited to the NT- group, both parameters were positively associated with systolic BP. Discussion: Our results demonstrate for the first time the existence in men of a close association between urinary hyaluronidase activity and vasopressinergic system and suggest that NT+ subjects have a reduced ability to respond to water loading possibly contributing to the blood volume expansion involved in early-stage hypertension. Considering these data, AVP could play a central role in BP regulation by affecting water metabolism through both hyaluronidase activity and AQP2 channel expression. [ABSTRACT FROM AUTHOR]

Multiple changes occur across various endocrine systems as an individual ages. The understanding of the factors that cause age-related changes and how they should be managed clinically is evolving. This statement reviews the current state of research in the growth hormone, adrenal, ovarian, testicular, and thyroid axes, as well as in osteoporosis, vitamin D deficiency, type 2 diabetes, and water metabolism, with a specific focus on older individuals. Each section describes the natural history and observational data in older individuals, available therapies, clinical trial data on efficacy and safety in older individuals, key points, and scientific gaps. The goal of this statement is to inform future research that refines prevention and treatment strategies in age-associated endocrine conditions, with the goal of improving the health of older individuals. [ABSTRACT FROM AUTHOR]

The karst carbon sink caused by rock outcrops results in enrichment of the bicarbonate in soil, affecting the physiological process of plants in an all-round way. Water is the basis of plant growth and metabolic activities. In heterogeneous rock outcrop habitats, the impact of bicarbonate enrichment on the intracellular water metabolism of plant leaf is still unclear, which needs to be revealed. In this paper, the Lonicera japonica and Parthenocissus quinquefolia plants were selected as experimental materials, and electrophysiological indices were used to study their water holding, transfer and use efficiency under three simulated rock outcrop habitats, i.e., rock/soil ratio as 1, 1/4 and 0. By synchronously determining and analyzing the leaf water content, photosynthetic and chlorophyll fluorescence parameters, the response characteristics of water metabolism within leaf cells to the heterogeneous rock outcrop habitats were revealed. The results showed that the soil bicarbonate content in rock outcrop habitats increased with increasing rock/soil ratio. Under the treatment of a higher concentration of bicarbonate, the leaf intra- and intercellular water acquisition and transfer efficiency as well as the photosynthetic utilization capacity of P. quinquefolia decreased, the leaf water content was lower, and those plants had low bicarbonate utilization efficiency, which greatly weakened their drought resistance. However, the Lonicera japonica had a high bicarbonate use capacity when facing the enrichment of bicarbonate within cells, the above-mentioned capacity could significantly improve the water status of the leaves, and the water content and intracellular water-holding capacity of plant leaves in large rock outcrop habitats were significantly better than in non-rock outcrop habitats. In addition, the higher intracellular water-holding capacity was likely to maintain the stability of the intra- and intercellular water environment, thus ensuring the full development of its photosynthetic metabolic capacity, and the stable intracellular water-use efficiency also made itself more vigorous under karstic drought. Taken together, the results suggested that the water metabolic traits of Lonicera japonica made it more adaptable to karst environments. [ABSTRACT FROM AUTHOR]

Aquaporins (AQPs) are a family of transmembrane proteins expressed in various organ systems. Many studies have shown that the abnormal expression of AQPs is associated with gastrointestinal, skin, liver, kidneys, edema, cancer, and other diseases. The majority of AQPs are expressed in the digestive system and have important implications for the physiopathology of the gastrointestinal tract as well as other tissues and organs. AQP regulators can prevent and treat most gastrointestinal-related diseases, such as colorectal cancer, gastric ulcer, and gastric cancer. Although recent studies have proposed clinically relevant AQPtargeted therapies, such as the development of AQP inhibitors, clinical trials are still lacking and there are many difficulties. Traditional Chinese medicine (TCM) has been used in China for thousands of years to prevent, treat and diagnose diseases, and is under the guidance of Chinese medicine (CM) theory. Herein, we review the latest research on the regulation of AQPs by TCMs and their active components, including Rhei Radix et Rhizoma, Atractylodis macrocephalae Rhizoma, Salviae miltiorrhizae Radix et Rhizoma, Poria, Astragali radix, and another 26 TCMs, as well as active components, which include the active components include anthraquinones, saponins, polysaccharides, and flavonoid glycosides. Through our review and discussion of numerous studies, we attempt to explore the regulatory effects of TCMs and their active components on AQP expression in the corresponding parts of the body in terms of the Triple Energizer concept in Chinese medicine defined as "upper energizer, middle energizer, and lower energizer,"so as to offer unique opportunities for the development of AQPrelated therapeutic drugs for digestive system diseases. [ABSTRACT FROM AUTHOR]

The headwaters of the Orinoco are being transformed into an extractive frontier and experiencing drastic water depletion in the dry season. We use the concept of water metabolism to illustrate the impact of the energy sector in a region typically identified with agriculture. Results indicate that oil palm irrigation for biofuel production together with the disposal of production water from oil extraction account for surface water availability being fully allocated during the dry season. We use ranges in water data and generate scenarios to account for the uncertainty generated by inadequate water-use regulation and limited data availability. [ABSTRACT FROM AUTHOR]

Sociohydrology was launched as the science dealing with feedbacks between coupled human and water systems. Much of the early work in sociohydrology involved studies in spatially isolated domains (e.g., river basins) dealing with phenomena that involved emergent patterns in the time domain, with a focus on formulating and testing hypotheses about how they arise. The papers collected in this Special Section "Sociohydrology: Spatial and Temporal Dynamics of Coupled Human‐Water Systems" illustrate that the scientific scope of sociohydrology has broadened over the last few years, with a rich diversity of phenomena studied and an expansion of the knowledge foundations and methodologies applied. These Special Section papers now incorporate methodologies and approaches from a wide range of social science disciplines, including anthropology, complex systems, economics, and sociology. The major themes tackled by these papers are understanding (i) water metabolism—the economic use of water; (ii) interactions between humans and droughts; (iii) interactions between humans and floods; and (iv) the role of human institutions, policy, and management. These collected papers provide a foundation for future research that strives to understand how to achieve water resources sustainability (society to water) and reduce the risk of hydrological hazards in society (water to society). Going forward, we suggest that the development of a common sociohydrology framework will be paramount for research development and student training. Additionally, increased engagement with the broader water management communities will enhance sociohydrology understanding and impact. Key Points: The foundation of sociohydrology are the many emergent phenomena that arise during the practice of water resources managementSociohydrology studies benefit from the concepts and methodologies drawn from a wide range of natural and social science disciplinesIncreased engagement with the broader water management communities and the development of common frameworks represent important issues for sociohydrology going forward [ABSTRACT FROM AUTHOR]

This paper presents key findings from an 'immersion' that was undertaken in August 2017 on Paquetá and surrounding islands within the Amazon region of Brazil. In this research, immersion is understood as active participation in peoples' lives over a period of time and supported by other methods including observation, semi-structured interviews and co-mapping. This research adapted the urban metabolism concept commonly used to assess levels of sustainability and resilience, for application to the context of peripheral river islands located in the Tocantins river near the Brazilian city of Belém. It specifically focuses on factors that impact on people's behaviour in relation to water management, or what is described here as the 'island water metabolism'. This includes geographic, seasonal, local governance and social dimensions as well as dependence on the rising and falling tides of the river. [ABSTRACT FROM AUTHOR]

Access to extractive resources relies as much on technology and prices as it does on the power to designate ecological and economic meanings to water and other environmental goods. This paper examines the ways in which the mining industry uses scientific models to create meanings for water that in turn legitimizes their access to and control over it. To do so, this paper explores the relevance of combining biophysical analyses-in this case water metabolism-with an examination of those power relations and social constructions that coexist with and affect the flows of water. Based on empirical research, this paper analyzes the evolution of water management in the process of copper production at the Cobre las Cruces mine in southern Spain to identify present contradictions in the strategies adopted by the mining company to avoid water degradation. These contradictions are revealed by examining how water has been framed as a resource not susceptible to being used for purposes other than mining processes. We argue that those framing this environmental explanation-the regional government and the mining industry-are promoting net subtractions of water from an aquifer against current regulations. [ABSTRACT FROM AUTHOR]

Copyright of Anatolian Journal of Cardiology / Anadolu Kardiyoloji Dergisi is the property of KARE Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Human societies and ecosystems use water in different ways and at different scales, which complicates the study of water-use sustainability in socioecological systems. We present a multiscale integrated assessment of societal and ecosystem metabolism, an innovative approach to the quantitative analysis of water use that addresses the problem of multiple scales. It builds on the concept of metabolic pattern and the flow -- fund model of Georgescu-Roegen. We show how to define water resources and water use (expressed in hourly rates) for socioeconomic systems in relation to the identities of relevant fund elements (relevant categories of human activity or land use) over a time span of 1 year. Similarly, we define the limits on the human appropriation of water (aggregate withdrawal or damping per year) on the basis of the structural and functional stability of ecological funds (defined over a much longer time scale) and the related land-use pattern. [ABSTRACT FROM AUTHOR]

Copyright of Turkish Journal of Endocrinology & Metabolism is the property of Aves Yayincilik Ltd. STI and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In Tunisia, it was reported that Meriones shawi, a desert rodent, was contaminated by heavy metals around several industrial sites. In the present study, the effects of cadmium (Cd) on water metabolism regulation was studied in adult male Meriones shawi that received contaminated diet with cadmium chloride (CdCl2) for 8 days at (1 g Cd/1 L H2O/1.5 kg of granule flour). Expression of arginine-vasopressin (AVP), a crucial hormone for water regulation, was studied by immunohistochemistry in the hypothalamic supraoptic nucleus and paraventricular nucleus. Inspite of variations in water intake, Meriones shawi successfully maintained a balance between water influx and efflux. Cd treatment did not modify water flux rates. Total body water volume remained constant during the treatment in all groups studied. In contrast to what is known in laboratory rodents, water restriction induced an increase in expression of AVP in both supraoptic nucleus and paraventricular nucleus after eight days and two weeks of the experiment, respectively. A similar effect was also observed by treating Meriones with Cd. However, expression of AVP immunoreactivity from deprived water animals in the presence of Cd was markedly and significantly lower than in the absence of Cd. We conclude that Cd exposure modifies the vasopressinergic neuronal system and provides information regarding the neurotoxicity risks that this element presents for mammals and human populations exposed to even low amounts of Cd, without directly affecting water metabolism. Suitability of Meriones shawi as an accumulation bioindicator for Cd was also confirmed in this study. [ABSTRACT FROM AUTHOR]

Little is known about prostaglandin F2α in cardiovascular homeostasis. Prostaglandin F2α. dose-dependently elevates blood pressure in WT mice via activation of the F prostanoid (FP) receptor. The FP is expressed in preglomerular arterioles, renal collecting ducts, and the hypothalamus. Deletion of the FP reduces blood pressure, coincident with a reduction in plasma renin concentration, angiotensin, and aldosterone, despite a compensatory up-regulation of AT1 receptors and an augmented hypertensive response to infused angiotensin II. Plasma and urinary osmolality are decreased in FP KOs that exhibit mild polyuria and polydipsia. Atherogenesis is retarded by deletion of the FP, despite the absence of detectable receptor expression in aorta or in atherosclerotic lesions in Ldlr KOs; Although vascular TNFβ, inducible nitric oxide enzyme and TGFα, are reduced and lesional macrophages are depleted in the FP/Ldlr double KOs, this result reflects the reduction in lesion burden, as the FP is not expressed on macrophages and its deletion does not alter macrophage cytokine generation. Blockade of the FP offers an approach to the treatment of hypertension and its attendant systemic vascular disease. [ABSTRACT FROM AUTHOR]

Effect of water droplets placed onto rice ( Oryza sativa L.) leaves before inoculation with blast fungus Magnaporthe grisea (Hebert) Barr on disease severity and superoxide radical generation by the leaves was investigated. The leaves were inoculated by placement of spore suspension droplets. One day before, droplets of distilled water were placed to the same sites as an inoculum. It was found, that such a pretreatment decreased frequency of susceptible-type lesions by 2 to 2.5 times and increased that of symptomless outcome by 1.5 times in comparison with the nontreated control. Besides, the pretreatment enhanced superoxide radical generation in diffusates of healthy leaves of susceptible cultivar and in diffusates of infected leaves of resistant cultivar one day post inoculation. It is suggested that water contacting with the leaf surface for a rather long time washes out from its cells compounds possessing properties of plant endogenous elicitors. The latter induce superoxide radical formation by plants and, as a consequence, their disease resistance. This may be interpreted as plant adaptation to high humidity, which usually favors infections. [ABSTRACT FROM AUTHOR]

The growth and water metabolism of three common shrubs on the Loess Plateau were studied under soil with different water contents. Results showed that water consumption of those species decreased with the increase in drought stress, and water consumptions of these shrubs were different: Forsythia suspensa was the greatest, and Syringa oblata was the lowest. The growth rate of new branches and leaf area of three species were the fastest under adequate soil water conditions, and were the lowest under severe drought. Under the same water conditions, the growth of F. suspensa was the fastest while that of S. oblata was the slowest. The water content, proline and chlorophyll content of different species changed with the increase in soil water stress. The leaf water content of Periploca sepium and F. suspensa was obviously higher than that of S. oblata, while the leaf proline content of F. suspensa and S. oblata was lower than that of P. sepium. The ratio leaf chlorophyll a: b of F. suspensa and S. oblata decreased with the decrease in soil water content. Although these three shrubs had different mechanisms in response to drought stress, they all had higher drought resistance and could adapt to the drought condition on the Loess Plateau. This paper provided some bases for choosing tree species on the Loess Plateau. [ABSTRACT FROM AUTHOR]

Vasopressin and aldosterone are essential hormones in the regulation of water and sodium balance. Aldosterone regulates sodium reabsorption, although synergistic effects on collecting duct water permeability have been shown. We investigated the effects of 7-day aldosterone infusion or oral spironolactone treatment on water balance and aquaporin (AQP) 2 expression in rats with 21 days of lithium-induced nephrogenic diabetes insipidus (Li-NDI). In rats with Li-NDI, aldosterone markedly increased (271 ± 14 ml/24 h), whereas spironolactone decreased (74 ± 11 ml/24 h) urine production compared with rats treated with lithium only (120 ± 11 ml/24 h). Aldosterone increased free-water clearance and creatinine clearance, whereas spironolactone caused a decreased creatinine clearance but unchanged free-water clearance. Immunoblotting showed unchanged AQP2 expression in cortex/outer stripe of the outer medulla and inner medulla. In the inner stripe of the outer medulla aldosterone caused a decreased AQP2 expression, whereas spironolactone caused an increase compared with rats treated with lithium only. Semiquantitative confocal immunofluorescence microscopy of AQP2 immunolabeling showed reduced AQP2 expression in the apical plasma membrane domain in connecting tubule (CNT) and initial cortical collecting ducts (iCCD) in response to aldosterone-treated rats compared with rats treated with lithium only. Spironolactone significantly increased apical AQP2 expression in the iCCD compared with rats treated with lithium only. We also tested whether similar changes could be observed in vasopressin-deficient BB rats and found similar changes in urine production and subcellular AQP2 expression in the CNT and iCCD in response to aldosterone and spironolactone. This study shows that aldosterone treatment perturbs diabetes insipidus and is associated with AQP2 redistribution in CNT and iCCD likely mediated by the spironolactone-sensitive mineralocorticoid receptor. [ABSTRACT FROM AUTHOR]

A laboratory study investigated the metabolic physiology, and response to variable periods of water and sodium supply, of two arid-zone rodents, the house mouse ( Mus domesticus) and the Lakeland Downs short-tailed mouse ( Leggadina lakedownensis) under controlled conditions. Fractional water fluxes for M. domesticus (24 ± 0.8%) were significantly higher than those of L. lakedownensis (17 ± 0.7%) when provided with food ad libitum. In addition, the amount of water produced by M. domesticus and by L. lakedownensis from metabolic processes (1.3 ± 0.4 ml · day−1 and 1.2 ± 0.4 ml · day−1, respectively) was insufficient to provide them with their minimum water requirement (1.4 ± 0.2 ml · day−1 and 2.0 ± 0.3 ml · day−1, respectively). For both species of rodent, evaporative water loss was lowest at 25 °C, but remained significantly higher in M. domesticus (1.1 ± 0.1 mg H2O · g−0.122 · h−1) than in L. lakedownensis (0.6 ± 0.1 mg H2O · g−0.122 · h−1). When deprived of drinking water, mice of both species initially lost body mass, but regained it within 18 days following an increase in the amount of seed consumed. Both species were capable of drinking water of variable saline concentrations up to 1 mol · l−1, and compensated for the increased sodium in the water by excreting more urine to remove the sodium. Basal metabolic rate was significantly higher in M. domesticus (3.3 ± 0.2 mg O2 · g−0.75 · h−1) than in L. lakedownensis (2.5 ± 0.1 mg O2 · g−0.75 · h−1). The study provides good evidence that water flux differences between M. domesticus and L. lakedownensis in the field are due to a requirement for more water in M. domesticus to meet their physiological and metabolic demands. Sodium fluxes were lower than those observed in free-ranging mice, whose relatively high sodium fluxes may reflect sodium associated with available food. [ABSTRACT FROM AUTHOR]

Plasma osmolality, sodium and vasopressin were measured in 7 patients before and during long-term treatment with carbamezepine, under resting conditions, and following an oral water load of 20 ml/kg body weight. During carbamazepine treatment, the ability to excrete the oral water load was decreased, the urine/plasma osmolality ratio was higher, and the free water clearance was lower. In two patients, the ability to excrete the oral water load was severely impaired, and the free water clearance remained negative following water loading. Plasma osmolality and sodium concentration were significantly lower during carbamazepine administration, but despite this the plasma vasopressin concentration remained unchanged or was even slightly increased. Four patients showed inappropriately high vasopressin concentrations in relation to the corresponding plasma osmolality when taking carbamazepine. The findings suggest a decrease in plasma osmolality during carbamazepine treatment, which might account for the inappropriate secretion of vasopressin. The latter might cause clinical symptoms of water intoxication, as has previously been reported in a few patients on carbamazepine therapy. [ABSTRACT FROM AUTHOR]

The diffusional water permeability of collecting ducts in vitro and the cyclic A.M.P. content of isolated papillae were measured after exposure to different concentrations of antidiuretic hormone, isoproterenol and noradrenalin. Antidiuretic hormone 25 μ units/ml. caused a 25% increase in diffusional water permeability. This response was not affected by isoproterenol (10 M) or noradrenalin (2 ×10 M). Antidiuretic hormone 100 μ unit ml caused a 50% increase in diffusional water permeability which likewise was not altered by isoproterenol or noradrenalin. Isoproterenol (10 M) and noradrenalin (2×10 M) had no significant effect on basal levels of diffusional water permeability. Isoproterenol had no significant effect on the tissue concentration of cyclic A.M.P. or on the increase in cyclic A.M.P. concentration induced by antidiuretic hormone. Noradrenalin (2×10 and 10) had no significant effect on basal cyclic A.M.P. concentration. However, noradrenalin inhibited the stimulation of cyclic A.M.P. induced by antidiuretic hormone. This effect was inhibited by phentolamine. This study suggests that catecholamines do not alter water handling by a direct action on the water permeability of the kidney but probably exert their action through an effect of A.D.H. release. [ABSTRACT FROM AUTHOR]

Laying hens are increasingly kept in barn or free-range systems, which not only allows birds to move freely but also potentially entails higher energy expenditures due to higher locomotor activity. Therefore, the aim of our study was to quantify the daily energy expenditure (DEE) and water turnover in freely moving laying hens. For that purpose, 10 Lohmann Selected Leghorn (LSL) and 10 Lohmann Brown (LB) hens were obtained from a conventional breeding company at 17 weeks of age. The trial started when birds reached an age of 34 weeks. All 20 birds were kept together in the same littered floor pen (12.1 m2). The pen was equipped with perches, a nest box, feeding and nipple drinkers. The DEE was determined individually for all experimental birds (n = 20) for a total of nine days using the doubly labelled water (DLW) method. Lohmann Brown hens were heavier than LSL hens, but laying rate did not differ between the two breeds, that is, one egg per hen and day during the study period. Average egg mass was 63.1 ± 0.20 g in LB and 61.7 ± 0.12 g in LSL hens, which converted to an egg energy content of 420 and 410 kJ/egg, respectively. Dilution spaces for oxygen and hydrogen differed between the breeds but not the respective turnover rates. Total body water as a percentage of body mass (LB: 54.4%, LSL: 53.8%; SEM = 0.7, F 1,18 = 0.41, P = 0.513) and total water intake (TWI) per day (LB: 275 ml/day, LSL: 276 ml/day; SEM = 20, F 1,17 = 0, P = 0.994) did not differ between LB and LSL hens. Individual DEE increased with body mass in LB but not in LSL hens. Average DEE did not differ between the two breeds (LB: 1 501 kJ/day; LSL: 1 520 kJ/day; SEM = 32.1, F 1,17 = 2.54, P = 0.131). However, when comparing the DEE on a metabolic mass basis, LSL hens expended with 984 kJ/kg0.75 on average significantly more energy per day than LB hens (895 kJ/kg0.75; SEM = 20.3, F 1,18 = 10.1, P = 0.005). Our results suggest that the DLW technique is a viable method to measure the energy expenditure and water turnover over several days in laying hens. Furthermore, we show that laying hens kept in floor pens fit into the general pattern of DEE among wild birds. [ABSTRACT FROM AUTHOR]

Background: The present work aimed to investigate the impact of partial replacement yellow corn by mango seed kernels (MSK) at different levels of (0, 25, and 50%) on feed and water consumption, water metabolism, nutrient digestibility, nitrogen balance, and rumen fluid parameters. Methods: Twelve mature male Rahmani sheep of about 58.39 ± 1.22 kg live body weight on average were used to investigate the influence of replacing yellow corn contents (45% in the control ration) by mango seed kernels (MSK) at different levels (0, 25, and 50%) that equal (0, 11.25, and 22.5% of total ration contents) on feed and water intakes, water metabolism, nutrient digestibility coefficients, nitrogen utilization, and some rumen fluid parameters. The animals were randomly assigned to three experimental groups (four animals in each treatment). Sheep fed rations are composed of 50% concentrate feed mixture (CFM) and 50% peanut vein hay (PVH) at portion 3% dry matter (DM) of live body weight (LBW). Results: The results showed that values of crude protein (CP), crude fiber (CF), and nitrogen-free extract (NFE) of MSK and yellow corn were similar. Meanwhile, MSK has superior ether extract content compared to yellow corn; meanwhile, ash content of yellow corn was lower than ash content of MSK. All tested CFM were isonitrogenous (16.17% CP), but it differs in their contents of gross and digestible energy. On the other hand, all experimental total mixed rations (TMR) were isonitrogenous (14.52% CP) and isocaloric (4177 kcal/kg DM in average). Dietary treatments significantly (P < 0.05) decreased total dry matter intake (DMI) and crude protein intake (CPI) that expressed as (g/h/day, g/kgW0.75, and kg/100 kg LBW) or gross energy intake (GEI) and digestible energy intake (DEI) that expressed as (Mcal/h/day, kcal/kgW0.75, and Mcal/100 kg LBW). Inclusion MSK in sheep ration insignificantly (P > 0.05) increased drinking water by 20% and 6.89% for experimental groups fed TMR2 and TMR3, respectively, compared to the control one (TMR1). Incorporation MSK in the rations significantly (P < 0.05) increased insensible losses of water. Dietary treatments significantly (P < 0.05) increased nutrient digestibility coefficients of DM, organic matter (OM), CP, CF, and NFE. Meanwhile, it significantly (P < 0.05) decreased EE digestibility. On the other hand, both values of total digestible nutrient (TDN) and digestible crude protein (DCP) were significantly (P < 0.005) improved. Nitrogen retention (NR) (NR % of nitrogen intake (NI) and NR % of digested nitrogen (DN)) values were significantly (P < 0.05) increased with increasing level of MSK in the sheep ration. Inclusion MSK significantly (P < 0.05) increased ruminal pH; however, it had no significant (P > 0.05) on both ammonia nitrogen (NH3-N) and total volatile fatty acid (TFVA) concentrations. Sampling time at 3 h post feeding significantly (P < 0.05) decreased ruminal pH in comparison with before and 6 h post feeding; meanwhile, sampling time had no significant effect (P > 0.05) on NH3-N concentration. Dietary treatment significantly (P < 0.05) increased the interaction between treatments and sampling time for ruminal pH. However, no interaction between treatments and sampling time was observed for both NH3-N and TVFA concentrations. Conclusion: The present results revealed that replacement up to 50% of yellow corn by MSK as alternative source of energy could be useful in feeding sheep without any adverse effect on digestion and fermentation processing. Also, it can be used to depress the rations cost. [ABSTRACT FROM AUTHOR]

Changes in plasma insulin in response to a physiological or pathophysiological elevation in circulating atrial natriuretic factor (ANF) have been investigated. Plasma insulin, glucose, immunoreactive (ir) ANF, effective renal plasma flow (ERPF), glomerular filtration rate (GFR), absolute and fractional excretion of sodium (FENa), have been measured in 14 volunteers before and during infusion of low doses of ANF or vehicle (V). Each subject received single-blind in a randomized sequence at 2 week-intervals: V alone, or ANF 4, 8 and 16 ng·kg·min, indused over 90 min. Plasma irANF was increased 2.5- to 11-fold during the ANF infusion as compared to the test with the vehicle. Plasma insulin did not change during V administration (baseline vs V: 22 vs 21 μU·ml) and was unchanged during ANF at 4, 8 and 16 ng·kg·min (19, 19, 21 μU·ml, respectively). Blood pressure, ERPF and GFR were not affected, and diuresis, FENa and urinary Na excretion were increased significantly and dose-dependently during ANF, but not V infusion. Compared to baseline, ANF 4, 8 and 16 ng·kg·min increased urinary Na excretion by 147, 241 and 446 μmol·min, respectively. The findings indicate that, in normal humans, an acute increase in irANF within or slightly above the physiological range, which modified natriuresis and diuresis, did not alter circulating plasma insulin. [ABSTRACT FROM AUTHOR]

Aim: While the diuretic action of acute ingestion of alcohol has been studied extensively, the effect of chronic alcohol consumption has received less attention. The aim of the present study was to investigate the effect of chronic alcohol consumption on the balance of water intake and excretion and certain renal functions in rats during a period of 12 months. Animals and Study Design: Male Wistar rats received either alcohol (15% v/v; group A, n = 65) or tap water (group C, n = 35) as drinking fluid. Urine and faeces were collected from 6 rats of each group during 7 days, at monthly intervals. In further experiments, the animals received a low-protein/high-fat diet with and without alcohol. Results: When the rats were fed the standard diet, 24-hour urine excretion was significantly reduced in group A compared with group C. This difference was even more pronounced when the animals were fed the low-protein/high-fat diet. The reduced urine excretion was not due to lower liquid consumption and the pattern of daily excretion of faeces was comparable with that observed for urine excretion. Both sodium and potassium excretion and the diuretic response to an acute water load were significantly reduced in group A compared with group C. The changes in water balance induced by chronic alcohol consumption were reversible within a few days when the rats received water instead of 15% alcohol. Conclusions: Chronic alcohol consumption has an antidiuretic effect in rats. The percentage of total ingested fluid leaving the body as hidden water loss increases after alcohol consumption by up to 25–26% over control values. Copyright © 2004 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]