Intravenous Administration Of Saline Research Articles

Saline versus Balanced Crystalloids for Adults with Aneurysmal Subarachnoid Hemorrhage: A Subgroup Analysis of the SMART Trial.

Whether the composition of intravenous crystalloid solutions affects outcomes in adults with aneurysmal subarachnoid hemorrhage (aSAH) remains unknown. Therefore, we determined whether the use of saline is associated with lower risk of disability and death in aSAH patients compared to balanced crystalloids. We conducted a post hoc subgroup analysis of the Isotonic Solutions and Major Adverse Renal Events Trial (SMART), a pragmatic, unblinded, cluster-randomized, multiple-crossover clinical trial that enrolled 15,802 adults between June 2015 and April 2017. We compared intravenous administration of saline to balanced crystalloids in consecutively enrolled aSAH patients aged 18 years or older whose ruptured aneurysm was procedurally secured at a single academic center in the United States. The primary outcome was the score on the modified Rankin scale (mRS, range, 0 [no symptoms] to 6 [death]) at 90 days obtained from a prospective institutional stroke registry. Secondary outcome included death by 90 days. Logistic or proportional odds regression models were used to test for between-group differences adjusted for age, hypertension, aSAH grade, and procedure type. Of the 79 aSAH patients procedurally treated during the SMART study period, 78 were enrolled (median age, 58 years; IQR, 49 to 64.5; 64% female), with 41 (53%) assigned to saline and 37 (47%) to balanced crystalloids. Plasma-Lyte was the primary balanced crystalloid used. Among 72 patients with 90-day mRS assessment, the adjusted common odds ratio, aOR, for mRS was 0.68 (95% CI, 0.28-1.63; P=0.39), with values less than 1.0 favoring saline. By 90 days, 2/39 patients (5%) in the saline group and 9/35 (26%) in the balanced-crystalloids group had died (aOR, 0.06; 95% CI, 0.00-0.50; P=0.02). Among procedurally treated aSAH patients, the risk of disability or death at 90 days did not significantly differ between saline and balanced crystalloids. Death occurred less frequently with saline than balanced crystalloids.

What is the optimal lipid emulsion for preventing intestinal failure-associated liver disease following parenteral feeding in a rat model of short-bowel syndrome?

PurposeComposite lipid emulsion (CLE) has been used for intestinal failure-associated liver disease (IFALD) to compensate for the disadvantages of soybean oil lipid emulsion (SOLE) or fish oil lipid emulsion (FOLE). However, the influence of its administration is unclear. We evaluated the effects of these emulsions on IFALD using a rat model of the short-bowel syndrome.MethodsWe performed jugular vein catheterization and 90% small bowel resection in Sprague–Dawley rats and divided them into four groups: control (C group), regular chow with intravenous administration of saline; and total parenteral nutrition co-infused with SOLE (SOLE group), CLE (CLE group) or FOLE (FOLE group).ResultsHistologically, obvious hepatic steatosis was observed in the SOLE and CLE groups but not the FOLE group. The liver injury grade of the steatosis and ballooning in the FOLE group was significantly better than in the SOLE group (p < 0.05). The TNF-α levels in the liver in the FOLE group were significantly lower than in the SOLE group (p < 0.05). Essential fatty acid deficiency (EFAD) was not observed in any group.ConclusionFish oil lipid emulsion attenuated hepatic steatosis without EFAD, while CLE induced moderate hepatic steatosis. The administration of CLE requires careful observation to prevent PN-induced hepatic steatosis.

Immunomodulation by systemic administration of human-induced pluripotent stem cell-derived mesenchymal stromal cells to enhance the therapeutic efficacy of cell-based therapy for treatment of myocardial infarction.

Rationale: Poor survival and engraftment are major hurdles of stem cell therapy in the treatment of myocardial infarction (MI). We sought to determine whether pre-transplantation systemic intravenous administration of human induced pluripotent stem cell (hiPSC)-derived mesenchymal stromal cells (hiPSC-MSCs) could improve the survival of hiPSC-MSCs or hiPSC-derived cardiomyocytes (hiPSC-CMs) following direct intramyocardial transplantation in a mouse model of MI.Methods: Mice were randomized to undergo intravenous administration of saline or 5×105 hiPSC-MSCs one week prior to MI, induced by ligation of the left anterior descending coronary artery. Mice were further assigned to undergo direct intramyocardial transplantation of hiPSC-MSCs (1×106) or hiPSC-CMs (1×106) 10 minutes following MI. Echocardiographic and invasive hemodynamic assessment were performed to determine cardiac function. In-vivo fluorescent imaging analysis, immunofluorescence staining and polymerase chain reaction were performed to detect cell engraftment. Flow cytometry of splenic regulatory T cells (Tregs) and natural killer (NK) cells was performed to assess the immunomodulatory effects.Results: Pre-transplantation systemic administration of hiPSC-MSCs increased systemic Tregs activation, decreased the number of splenic NK cells and inflammation, and enhanced survival of transplanted hiPSC-MSCs and hiPSC-CMs. These improvements were associated with increased neovascularization and decreased myocardial inflammation and apoptosis at the peri-infract zone with consequent improved left ventricular function four weeks later. Co-culture of splenic CD4 cells with hiPSC-MSCs also modulated their cytokine expression profile with a decreased level of interferon-γ, tumor necrosis factor-α, and interleukin (IL)-17A, but not IL-2, IL-6 and IL-10.Conclusion: Pre-transplantation systemic intravenous administration of hiPSC-MSCs induced immunomodulation and facilitated the survival of intramyocardially transplanted cells to improve cardiac function in MI.

Radiocontrast Toxicity.

Intravenous and intraarterial contrast media are invaluable tools in the diagnosis of anatomic lesions. However, they have been associated with deleterious renal events, ranging from acute kidney injury (iodinated contrast) to nephrogenic systemic fibrosis (gadolinium-containing agents). Contrast-associated acute kidney injury has a wide incidence, likely due to differences in populations studied, with incidence likely overstated due to comorbid conditions at the time of contrast exposure. Pathophysiology includes hemodynamic and direct toxic effects. Preventative strategies include intravenous saline administration, higher urine pH, and statin administration. Importantly, because of fears of contrast-associated acute kidney injury, practitioners may be selecting only the healthiest patients for contrast exposure. Gadolinium-based contrast agents may cause their toxicity through being unbound from their ligand, and certain preparations may be less harmful than others.

Intravenous administration of L-tryptophan stimulates gastrointestinal hormones and melatonin secretions: study on beef cattle.

This study aimed to determine the effective dose of intravenous administration of L-tryptophan (L-T) on gastrointestinal hormones (GIH) secretions and melatonin using Hanwoo cattle. Three steers (362 ± 23 kg) fitted with indwelling jugular vein catheters were assigned in a 3 × 3 Latin square design. Treatments were intravenous administration of saline (control), 28.9 mg L-T/kg body weight (BW; low) and 57.8 mg L-T/kg BW (high) L-T for 1 day with 7 days of adaptation. Samples were collected after adaptation period at −60, 0, 30, 60, 90, 120, 150, 180, 240, and 300 min of sampling day. The levels of serum cholecystokinin (CCK) and secretin were higher (p < 0.05) in the high L-T group than those in the other groups. Serum Melatonin (MEL) levels were increased upon L-T administration (p < 0.05) in the high L-T group. Taken together, the effective dose of L-T administration was defined at 57.8 mg L-T/kg BW in order to stimulate increase of GIH and MEL.

Insulin and Glucagon Interaction Studied by Separate and Combined Receptor Antagonism

Insulin and glucagon are mutually influencing not only the actions of each other but also the secretion, which makes it very complicated to unravel their roles in integrated metabolism. Having studied in detail the actions of glucagon receptor antagonism in mice, we decided also to study the effects of insulin receptor antagonism and their combination. Female C57BL/6J mice (n=72) were administered an insulin receptor antagonist (IRA) (S961, 30 nmol/kg), a glucagon receptor antagonist (GRA) (25-2648, 100 mg/kg), or both IRA and GRA (IRA+GRA) three hours before intravenous administration of saline, glucose (0.5g/kg) or amino acids (1 µmol/g) (both antagonists were generous gifts from Novo Nordisk A/S). As expected, IRA caused hyperglycemia (15.6±1.0 mM vs. 8.4±0.3mM, P&amp;lt;0.0001) and hyperinsulinemia (51.07±3.44ng/mL vs. 0.72±1.19ng/mL, P&amp;lt;0.0001) at fasting, but reduced glucose-induced inhibition of glucagon secretion (dAUC0-20 min; -114.0±24.0min × pM vs. dAUC0-20 min; -211.8±10.4 min × pM, P&amp;lt;0.0001). GRA treatment resulted in mild hypoglycemia (P=0.03), hyperglucagonemia (P=0.04), and did not influence insulin secretion (P=0.9) at fasting. However, after administration of both IRA and GRA, insulin secretion was significantly reduced (31.36±3.0 ng/mL vs. 51.07±3.44 ng/mL, P&amp;lt;0.0001). Finally, GRA+IRA administration resulted in blood glucose concentrations equal to those of vehicle treated mice upon a glucose challenge (tAUC0-20 min; 342.7±29.3 mmol × min vs. 353.1±39.1 mmol × min, P=0.6). In conclusion, using both glucagon and insulin receptor antagonists, it can be demonstrated in mice that both hormones are essential for the maintenance of fasting glucose metabolism and that the secretion of both is regulated by powerful negative feedback mechanisms. Insulin contributes to glucose-induced inhibition of glucagon secretion, while glucagon has a positive effect on insulin secretion. Disclosure K.D. Galsgaard: None. J.J. Holst: Advisory Panel; Self; Novo Nordisk A/S. Board Member; Self; Zealand Pharma A/S. Speaker's Bureau; Self; Merck Sharp &amp; Dohme Corp., AstraZeneca. Research Support; Self; Danish Diabetes Academy, Novo Nordisk Foundation. Other Relationship; Self; Antag Therapeutics. Other Relationship; Spouse/Partner; Antag Therapeutics. M. Winther-Soerensen: None. N.J. Wewer Albrechtsen: Speaker's Bureau; Self; Merck Sharp &amp; Dohme Corp.. Other Relationship; Self; Mercodia, Alpco. J. Pedersen: None.

Non-uniform relationship between salt status and aldosterone activity in patients with chronic kidney disease

Hypertension is prevalent in chronic kidney disease (CKD). Studies suggest that reduction in dietary salt intake reduces blood pressure (BP). We studied relationships between salt intake, BP and renin-angiotensin system regulation in order to establish if it is disordered in CKD. Mechanistic crossover study of CKD patients versus non-CKD controls. Participants underwent modified saline suppression test prior to randomization to either low or high salt diet for 5 days and then crossed over to the alternate diet. Angiotensin-II stimulation testing was performed in both salt states. BP, urea and electrolytes, and plasma aldosterone concentration (PAC) were measured. Twenty-seven subjects were recruited (12 CKD, 15 control). There was no difference in age and baseline BP between the groups. Following administration of intravenous saline, systolic BP increased in CKD but not controls (131 ± 16 to 139 ± 14 mmHg, P=0.016 vs 125 ± 20 to 128 ± 22 mmHg, P=0.38). Median PAC reduced from 184 (124,340) to 95 (80,167) pmol in controls (P=0.003), but failed to suppress in CKD (230 (137,334) to 222 (147,326) pmol (P=0.17)). Following dietary salt modification, there was no change in BP in either group. Median PAC was lower following high salt compared with low salt diet in CKD and controls. There was a comparable increase in systolic BP in response to angiotensin-II in both groups. We demonstrate dysregulation of aldosterone in CKD in response to salt loading with intravenous saline, but not to dietary salt modification.

Intravenous saline administration in patients with severe acquired brain injury and orthostatic intolerance for tilt-table mobilization

ABSTRACTPrimary objective: This study aimed to investigate the effect of intravenous saline administration on orthostatic hypotension (OH) during head up tilt (HUT) and the change in the renin–angiotensin–aldosterone system before and after HUT in patients with severe acquired brain injury (ABI).Research design: The study is designed as an observational study.Methods and procedures: Fourteen patients with ABI, low level of consciousness and OH were monitored before, during and after HUT with non-invasive beat-to-beat blood pressure measurement, and transcranial Doppler determination of middle cerebral artery blood flow velocity. Blood samples were collected before and after two HUT sessions separated by 1 hour and saline was administered in between.Main outcomes and results: Patients’ ability to stand upright did not change after saline administration due to OH. The patients showed signs of reduced cerebral autoregulation at both HUT sessions. The patients had a significant lower level of renin and angiotensin II but not aldosterone.Conclusions: Patients with severe ABI and OH demonstrate no improvement in standing time with reduced plasma renin and angiotensin II after two HUT sessions and 1 hour fluid administration. Research focusing on the ability to retain fluid after bed rest is warranted.

Target-controlled infusion of propofol and remifentanil combined with dexmedetomidine reduces functional endoscopic sinus surgery bleeding.

The aim of the present study was to investigate the effects of target-controlled infusion (TCI) of propofol and remifentanil combined with dexmedetomidine on functional endoscopic sinus surgery (FESS) bleeding and surgical field. 62 patients scheduled to undergo FESS were randomly divided into experimental group (intravenous 0.5 µg kg-1 h-1 dexmedetomidine after 0.5 µg kg-1 bolus within 15 min until the end of surgery) or control group (intravenous saline administration at the same dose). All patients underwent endotracheal intubation under general anesthesia with TCI of propofol and remifentanil for anesthesia induction and maintenance. During anesthesia, arterial pressure (MAP), heart rate (HR), intraoperative propofol and remifentanil dosage and intraoperative blood loss were recorded. Surgeons rated their satisfaction with the surgical field using the Numeric Rating Scale (NRS). Following surgery, visual analog scale (VAS) was assessed. During tracheal intubation and extubation, HR and MAP in the experimental group were significantly lower compared with the control group (P<0.05); HR was also significantly lower compared with the control group throughout surgery (P<0.05). The mean infusion rate of propofol and remifentanil was significantly lower in the experimental group compared with the control group (P=0.001 and P=0.045, respectively). Blood loss in the experimental group was significantly lower compared with the control group (P=0.007). NRS and VAS scores in the experimental group were significantly improved compared with control group (P<0.01). In conclusion, TCI of propofol and remifentanil for FESS combined with dexmedetomidine reduced intraoperative bleeding and improved the quality of surgical field compared with the same procedure without dexmedetomidine. Dexmedetomidine also reduced the increase in MAP and HR during tracheal intubation and extubation, and improved postoperative analgesia quality.

The effect of NaCl on the level of reduced sulfur compounds in rat liver. Implications for blood pressure increase.

It is commonly known that excessive salt intake is a risk factor of hypertension. Currently, there is an increasing interest in reduced reactive sulfur species (RSS), mainly H2S and sulfane sulfur (SS) as new gasotransmitters showing vasorelaxant properties. The aim of the present study was to determine the effect of repeated administration of low sodium chloride dose included in physiological saline on blood pressure, on the level of RSS and activity of enzymes involved in their biosynthesis in the rat. Two separate experiments were carried out on male Wistar rats: one with intravenous injections of saline and the second one with intraperitoneal saline injections. Blood pressure was measured during the experiment. The level of RSS and other biochemical assays were conducted in the rat liver, because of an intense cysteine metabolism to RSS in this organ. Intravenous administration of saline induced a significant increase in systolic blood pressure while intraperitoneal injections showed only a tendency towards increasing blood pressure. The RSS (H2S and SS) level as well as the activity of the main enzyme responsible for their production in the liver of animals after iv saline injections were decreased. Animals injected with physiological saline by ip route did not reveal any statistically significant differences in SS, H2S, and activities of sulfurtransferases, although a tendency to decrease in the RSS was observed. The repeated iv saline injection induced a slight hypertension accompanied by disturbances in anaerobic cysteine metabolism in the rat liver.

Effects of acute psychological stress on placebo and nocebo responses in a clinically relevant model of visceroception.

There is evidence to suggest a role of emotions in placebo and nocebo effects, but whether acute psychological stress changes the magnitude of placebo or nocebo responses has not been tested. In a clinically relevant model of visceroception, we assessed effects of acute psychological stress on changes in urgency and pain in response to positive or negative treatment suggestions. In 120 healthy volunteers, perceived urge-to-defecate and pain in response to individually calibrated rectal distensions were measured with visual analogue scales during a BASELINE. Participants then underwent the Trier Social Stress Test (N = 60) or a simple cognitive task (control, N = 60) and were randomized to positive (placebo), negative (nocebo), or neutral treatment information regarding intravenous administration of saline. The series of distensions was repeated, and changes in visual analogue scales from BASELINE to TEST were compared between groups using analysis of covariance and planned post hoc tests. Treatment information emerged as a main factor (P <0.001), supporting treatment information effects for both urgency and pain. Effects for urgency were modulated by stress (interaction effect: P <0.05): Positive information reduced urgency (P = 0.025), while negative information increased urgency (P = 0.026) only in stressed groups. For pain, effects of stress emerged for nocebo responses, which were only evident in stressed groups (P = 0.009). This is the first experimental study supporting effects of acute psychological stress on placebo and nocebo responses in visceroception. Results call for mechanistic as well as patient studies to assess how psychological stress shapes patients' treatment expectations and thereby affects health outcomes.

Efficacy of oral supplemental hydration for the prevention of contrast-induced nephropathy in rats.

To compare oral rehydration solution (ORS) with saline infusion for preventing contrast-induced nephropathy (CIN) in a rat model. Adult male Sprague-Dawley rats (310-360g) received intravenous indomethacin (10mg/kg), N G-nitro-L-arginine methyl ester (10mg/kg), and iohexol (10mL/kg) to induce acute contrast-induced renal injury (CIN group); control rats received saline only. For hydration, rats received either continuous infusion (20mL/kg/h) of saline or three oral doses (20mL/kg each) of ORS. Acute renal injury was evaluated by assaying urine collected for 24h beginning 2h before the contrast injection, evaluating blood taken 22h after the contrast injection, and examining the kidneys histopathologically. Hydration with saline prevented only the contrast-induced increase in plasma creatinine, whereas ORS prevented deleterious changes in plasma creatinine, blood urea nitrogen, and creatinine clearance as well as in urinary protein, albumin, and N-acetyl-D-glucosaminidase concentrations. Histopathologic changes noted in the CIN group were diminished in both saline and ORS groups. Both intravenous saline administration and oral hydration with ORS decreased the severity of CIN. Hydration with ORS was comparable to intravenous saline infusion in preventing CIN-associated abnormalities.

Distigmine Bromide Produces Sustained Potentiation of Guinea-Pig Urinary Bladder Motility by Inhibiting Cholinesterase Activity.

Distigmine is a cholinesterase (ChE) inhibitor used for the treatment of detrusor underactivity in Japan. Distigmine's pharmacological effects are known to be long-lasting, but the duration of its effect on urinary bladder contractile function has not been fully elucidated. The present study aimed to determine these effects in relation to the plasma concentrations of distigmine and its inhibition of ChE activities in blood, plasma, and bladder tissue. Intravesical pressures were recorded in anesthetized guinea-pigs for 12 h after the intravenous administration of saline or distigmine (0.01-0.1 mg/kg). Plasma distigmine concentrations were measured by liquid chromatograph-tandem mass spectrometry (LC-MS/MS), while ChE activities were assayed using 5,5'-dithiobis(2-nitrobenzoic acid). Distigmine (0.1 mg/kg) significantly increased the maximum intravesical pressure at micturition reflex for 12 h post-administration. In contrast, plasma distigmine was only detectable for 6 h post-administration in these animals and a one-compartment model calculated an elimination half-life of 0.7 h. However, bladder and blood acetylcholinesterase activities were significantly inhibited for 12 h after distigmine administration, although plasma ChE activities were not affected. The pharmacodynamic effects of distigmine thus persisted after its elimination from the circulation, indicating that it may bind to bladder acetylcholinesterase, producing sustained enzyme inhibition and enhancement of bladder contractility.

Comparison of the Intravenous and Epidural Administration of Tumor Necrosis Factor-alpha Antagonists in an Experimental Rat Pain Model.

Introduction:Inflammatory cytokines secreted from the nucleus pulposus are thought to lead to lumbar nerve root compression-like symptoms. Tumor necrosis factor-alpha (TNF-α), an inflammatory cytokine, likely plays an important role in lumbar disc hernia-related leg pain. In this experimental study, we compared the effectiveness of TNF-α antagonists administered through the intravenous or epidural route in lumbar spine pathologies.Materials and Methods:After ethics committee approval had been obtained, 24 Sprague Dawley male rats aged 70–90 days and weighing 250–300 g each were allocated to four groups. In Group I, only the surgical procedure was performed; in Group II, 1 ml of saline solution was administered into the epidural field; in Group III, 10 mg/kg of infliximab was administered into the coccygeal vein; and in Group IV (epidural group), 25 mg of etanercept was administered into the epidural region.Results:When the left leg pull values were analyzed on day 14, whereas there was not a significant difference among the three groups, a decreasing difference was observed in Group IV (P < 0.05). When the 21st and 28th day left leg pull values were compared between groups, the values from Groups II, III, and IV were significantly lower than those of Group I (P < 0.05).Conclusion:The absence of a difference between the baseline values and left leg pull values on days 14, 21, and 28 in Group IV indicates that recovery began on day 21 with the epidural administration of etanercept. There was no difference between intravenous saline administration and intravenous infliximab administration with regard to the start of the recovery. In the present study of rats with discopathy, TNF-α antagonists administered epidurally led to earlier recovery from radiculopathy-related allodynia compared to intravenous administration.

Ultrasonographic caval indices do not significantly contribute to predicting fluid responsiveness immediately after coronary artery bypass grafting when compared to passive leg raising.

BackgroundAppropriate fluid management is one of the most important elements of early goal-directed therapy after cardiothoracic surgery. Reliable determination of fluid responsivenss remains the fundamental issue in volume therapy.The purpose of the study was to assess the usefulness of dynamic IVC-derived parameters (collapsibility index, distensibility index) in comparison to passive leg raising, in postoperative fluid management in mechanically ventilated patients with left ventricular ejection fraction ≥ 30 %, immediately after elective coronary artery bypass grafting.MethodsProspective observational case series study including 35 patients with LVEF ≥ 30 %, undergoingelective coronary artery bypass grafting was conducted. Transthoracic echocardiography, passive leg raising and intravenous administration of saline were performed in all study subjects. Dynamic parameters derived from ultrasonographic assessment of the IVC diameter (collapsibility index–CI and distensibility index–DI), cardiac outputResultsThere were 24 (68.57 %) responders in the study population. There were no statistical differences between the groups in relation to: clinical parameters, pre- and postoperative LVEF, fluid balance and CVP. Change in cardiac output after passive leg raising correlated significantly with that after the volume expansion (p=0.000, r=0.822). Dynamic IVC derivatives were slightly higher in fluid responders, however this trend did not reach statistical significance. None of the caval indices correlated with fluid responsiveness.ConclusionDynamic IVC-derived parameters do not predict fluid responsiveness in mechanically ventilated patients with preserved ejection fraction immediately after elective coronary artery bypass grafting. Passive leg raising is not inferior to volume expansion in differentiating between fluid responders and nonresponders. Immediate fluid challenge after CABG is safe and well tolerated.Electronic supplementary materialThe online version of this article (doi:10.1186/s12947-016-0065-4) contains supplementary material, which is available to authorized users.

Glucose-dependent insulinotropic polypeptide augments glucagon responses to hypoglycemia in type 1 diabetes.

Glucose-dependent insulinotropic polypeptide (GIP) is glucagonotropic, and glucagon-like peptide-1 (GLP-1) is glucagonostatic. We studied the effects of GIP and GLP-1 on glucagon responses to insulin-induced hypoglycemia in patients with type 1 diabetes mellitus (T1DM). Ten male subjects with T1DM (C-peptide negative, age [mean ± SEM] 26 ± 1 years, BMI 24 ± 0.5 kg/m(2), HbA1c 7.3 ± 0.2%) were studied in a randomized, double-blinded, crossover study, with 2-h intravenous administration of saline, GIP, or GLP-1. The first hour, plasma glucose was lowered by insulin infusion, and the second hour constituted a "recovery phase." During the recovery phase, GIP infusions elicited larger glucagon responses (164 ± 50 [GIP] vs. 23 ± 25 [GLP-1] vs. 17 ± 46 [saline] min ⋅ pmol/L, P < 0.03) and endogenous glucose production was higher with GIP and lower with GLP-1 compared with saline (P < 0.02). On the GIP days, significantly less exogenous glucose was needed to keep plasma glucose above 2 mmol/L (155 ± 36 [GIP] vs. 232 ± 40 [GLP-1] vs. 212 ± 56 [saline] mg ⋅ kg(-1), P < 0.05). Levels of insulin, cortisol, growth hormone, and noradrenaline, as well as hypoglycemic symptoms and cognitive function, were similar on all days. Our results suggest that during hypoglycemia in patients with T1DM, exogenous GIP increases glucagon responses during the recovery phase after hypoglycemia and reduces the need for glucose administration.

The significance of early diagnosis of cancer-related hypercalcaemia

Cancer-related hypercalcaemia is one of the most common life-threatening metabolic disorders. It occurs in 20% to 30% of patients with cancer during the course of the disease, which depends on tumour type, too. There are two types of cancer-related hypercalcemia: humoral hypercalcemia and local osteolytic hypercalcaemia. Malignant hypercalcaemia is mediated by several circulating factors secreted by malignant cells. The biological actions of these factors are primarily stimulation of osteoclasts to resorb bone and, secondly, stimulation of calcium reabsorption at the renal tubules resulting in an elevation of serum calcium level. Diagnosis of hypercalcaemia is relatively difficult due to the non-specific clinical signs as well as the underlying malignancy and the side-effects of palliative medical treatment. Consequently, cancer-related hypercalcaemia is underdiagnosed quite often. Unrecognised malignant hypercalcaemia can lead to death. Nowadays 90% of hypercalcaemia can be treated with administration of intravenous saline containing fluids and bisphosphonates. Literature data suggest that hypercalcaemia is treated in less than 40% of hospitalized patients properly due to diagnostic errors and mismanagement.

Acute alcohol exposure, acidemia or glutamine administration impacts amino acid homeostasis in ovine maternal and fetal plasma

Fetal alcohol syndrome (FAS) is a significant problem in human reproductive medicine. Maternal alcohol administration alters maternal amino acid homeostasis and results in acidemia in both mother and fetus, causing fetal growth restriction. We hypothesized that administration of glutamine, which increases renal ammoniagenesis to regulate acid-base balance, may provide an intervention strategy. This hypothesis was tested using sheep as an animal model. On day 115 of gestation, ewes were anesthetized and aseptic surgery was performed to insert catheters into the fetal abdominal aorta as well as the maternal abdominal aorta and vena cava. On day 128 of gestation, ewes received intravenous administration of saline, alcohol [1.75 g/kg body weight (BW)/h], a bolus of 30 mg glutamine/kg BW, alcohol + a bolus of 30 mg glutamine/kg BW, a bolus of 100 mg glutamine/kg BW, alcohol + a bolus of 100 mg glutamine/kg BW, or received CO2 administration to induce acidemia independent of alcohol. Blood samples were obtained simultaneously from the mother and the fetus at times 0 and 60 min (the time of peak blood alcohol concentration) of the study. Administration of alcohol to pregnant ewes led to a reduction in concentrations of glutamine and related amino acids in plasma by 21-30%. An acute administration of glutamine to ewes, concurrent with alcohol administration, improved the profile of most amino acids (including citrulline and arginine) in maternal and fetal plasma. We suggest that glutamine may have a protective effect against alcohol-induced metabolic disorders and FAS in the ovine model.

Arginine nutrition and fetal brown adipose tissue development in diet-induced obese sheep

The global incidence of human obesity has more than doubled over the past three decades. An ovine model of obesity was developed to determine effects of maternal obesity and arginine supplementation on maternal, placental, and fetal parameters of growth, health, and well being. One-hundred-twenty days prior to embryo transfer, ewes were fed either ad libitum (n = 10) to induce obesity or 100% National Research Council-recommended nutrient requirements (n = 10) as controls. Embryos from superovulated ewes with normal body condition were transferred to the uterus of control-fed and obese ewes on day 5.5 post-estrus to generate genetically similar singleton pregnancies. Beginning on day 100 of gestation, obese ewes received intravenous administration of saline or L-arginine-HCl three times daily (81 mg arginine/kg body weight/day) to day 125, whereas control-fed ewes received saline. Fetal growth was assessed at necropsy on day 125. Maternal obesity increased (1) percentages of maternal and fetal carcass lipids and (2) concentrations of leptin, insulin, glucose, glutamate, leucine, lysine and threonine in maternal plasma while reducing (1) concentrations of progesterone, glycine and serine in maternal plasma and (2) amniotic and allantoic fluid volumes. Administration of L-arginine to obese ewes increased arginine and ornithine concentrations in maternal and fetal plasma, amniotic fluid volume, protein content in maternal carcass, and fetal brown adipose tissue (+60%), while reducing maternal lipid content and circulating leptin levels. Fetal or placental weight did not differ among treatments. Results indicate that arginine treatment beneficially reduces maternal adiposity and enhances fetal brown adipose tissue development in obese ewes.

Striatal adenosine A2A receptor-mediated positron emission tomographic imaging in 6-hydroxydopamine-lesioned rats using [18F]-MRS5425

A(2A) receptors are expressed in the basal ganglia, specifically in striatopallidal GABAergic neurons in the striatum (caudate-putamen). This brain region undergoes degeneration of presynaptic dopamine projections and depletion of dopamine in Parkinson's disease. We developed an (18)F-labeled A(2A) analog radiotracer ([(18)F]-MRS5425) for A(2A) receptor imaging using positron emission tomography (PET). We hypothesized that this tracer could image A(2A) receptor changes in the rat model for Parkinson's disease, which is created following unilateral injection of the monoaminergic toxin 6-hydroxydopamine (6-OHDA) into the substantia nigra. [(18)F]-MRS5425 was injected intravenously in anesthetized rats, and PET imaging data were collected. Image-derived percentage injected doses per gram (%ID/g) in regions of interest was measured in the striatum of normal rats and in rats unilaterally lesioned with 6-OHDA after intravenous administration of saline (baseline), D(2) agonist quinpirole (1.0 mg/kg) or D(2) antagonist raclopride (6.0 mg/kg). Baseline %ID/g reached a maximum at 90 s and maintained plateau for 3.5 min, and then declined slowly thereafter. In 6-OHDA-lesioned rats, %ID/g was significantly higher in the lesioned side compared to the intact side, and the baseline total %ID/g (data from both hemispheres were combined) was significantly higher compared to quinpirole stimulation starting from 4.5 min until the end of acquisition at 30 min. Raclopride did not produce any change in uptake compared to baseline or between the hemispheres. Thus, increase of A(2A) receptor-mediated uptake of radioactive MRS5425 could be a superior molecular target for Parkinson's imaging.