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Adrenocortical function in neonatal and weanling Beagle pups.
1995
Randolph J.F. | Center S.A. | Reimers T.J. | Scarlett J.M. | Corbett J.R.
Adrenocortical function was assessed in 27 Beagle pups at 2, 4, 6, 8, 10, and 12 weeks of age by determination of plasma sodium, potassium, and chloride concentrations; serum aldosterone and cortisol concentrations; and plasma ACTH concentrations. Serum cortisol concentration was measured before and 1 and 2 hours after IM administration of 2.2 IU of ACTH/kg of body weight. Serum progesterone concentration also was determined for all pups at 2, 4, and 6 weeks of age. Mean baseline cortisol concentration was lower for pups 8 weeks old or younger than for mature dogs. Nevertheless, mean serum ACTH-stimulated cortisol concentration in dogs of all age groups increased into the adult reference range after administration of ACTH. For pups 4 weeks old or younger, increase in cortisol concentration was maximal at 2 hours after ACTH administration. However, in pups between 6 and 12 weeks of age, the increase in cortisol concentration was maximal 1 hour after ACTH administration in about a third of the pups, whereas the remaining pups had peak values at 2 hours. Mean plasma sodium, potassium, and chloride concentrations for each age group were within the reference ranges established for mature dogs, with the exception of lower mean plasma sodium and chloride concentrations in pups 4 weeks old or younger. Mean serum aldosterone concentration in pups of each age group was substantially higher than the range of aldosterone concentrations for clinically normal mature dogs. Median progesterone concentration was uniformly less than 0.2 ng/ml for all pups 6 weeks old or younger. The normal endogenous ACTH concentration and adequate cortisol responses to exogenous ACTH seen in our pups would support functional pituitary gland and adrenal cortex for cortisol production. The low baseline cortisol concentration observed in the pups of this study may be related to reduced binding of cortisol to plasma proteins, as exists in human infants.
Afficher plus [+] Moins [-]In vitro effects of a mixture of Escherichia coli heat-stable enterotoxins on chloride flux in everted jejunal sacs of male pigs.
1988
Panichkriangkrai W. | Ahrens F.A.
In vitro effects of a mixture of Escherichia coli heat-stable enterotoxins (STa and STb) on isolated jejunum of 3-week-old male pigs were studied, using everted intestinal sac techniques. Heat-stable enterotoxins increased chloride secretion and chloride absorption in everted intestinal sacs. The increase of secretory flux was greater than that for absorptive flux. Vasoactive intestinal peptide (6 x 10-9M) increased chloride secretion, but had no effect on chloride absorption. Neither vasoactive intestinal peptide nor pilocarpine (10-5M) had additive effect to ST. Secretory effects of ST were not blocked by atropine 2 x 10-5M), clonidine (10-6M), or morphine (4.2 X 10-6M).
Afficher plus [+] Moins [-]Fractional excretion of electrolytes in lactating dairy cows.
1992
Fleming S.A. | Hunt E.L. | Brownie C. | Rakes A. | McDaniel B.
Samples of serum and urine were obtained simultaneously from 56 healthy lactating cows to determine ranges of fractional excretion (FE) of calcium (Ca), phosphate (PO4), magnesium (Mg), sodium (Na), potassium (K), and chloride (Cl). Samples were obtained at 3 stages of lactation: period 1 = 1 to 7 days, 2 = 83 to 112 days, and 3 = 175 to 197 days. The FE of electrolytes were significantly different among periods 1, 2, and 3 for Ca (P < 0.001), PO4 (P < 0.025) and Mg (P < 0.025), but were not significantly different for Na, K, and Cl. Least squares mean FE of Ca was lowest in period 1 and not significantly different for periods 2 and 3, whereas mean FE values for PO4 and Mg were highest in period 2 and not significantly different for periods 1 and 3. The mean FE values of Na, K, and Cl did not change with stage of lactation. Age and category of milk production (high, medium, and low) did not influence the FE values of the electrolytes.
Afficher plus [+] Moins [-]Replacement of chloride deficit by use of 1.8% NaCl to correct experimentally induced hypochloremic metabolic alkalosis in sheep.
1991
Fubini S.L. | Smith D.F. | Grohn Y.T. | Levine S.A. | Deuel D.M.
Five adult 40- to 50-kg female sheep were surgically fitted with a reentrant cannulae placed in the proximal part of the duodenum just distal to the pylorus. By diversion of abomasal outflow, this model has been shown to produce hypochloremic metabolic alkalosis accompanied by dehydration, hypokalemia, and hyponatremia. Each sheep was subjected to 3 separate, 12-hour IV treatment trials, in each case preceded by a control period of 48 hours, and a diversion period of 36 to 96 hours, during which a hypochloremic (Cl- less than or equal to 60 +/- 2 mEq/L) metabolic alkalosis with hypokalemia and hyponatremia was produced. Treatment 1, consisting of 6 L of isotonic Na gluconate, was designed to replace volume without replenishing the Cl- deficit. Although hydration improved, plasma Cl- decreased further, and the sheep became increasingly weak and depressed. Treatment 2, consisting of 2 L of 1.8% NaCl, was designed to replace the Cl- deficit without replacing total volume. Plasma Na+ and Cl- concentrations returned to normal during the 12 hours of treatment; acid-base balance and plasma K+ concentrations returned to normal within 36 hours of treatment. During treatment 3 (control, no treatment), measured metabolic values changed minimally. We concluded that the IV replacement of Cl- without K+ is effective in the correction of experimentally induced hypochloremic metabolic alkalosis in sheep.
Afficher plus [+] Moins [-]The characters of Ca2+ activated Cl- channel and its role in the cardiac myocytes.
1994
Park C.O. | Kim Y.M. | Haan J.H. | Hong S.G.
Estrogen-related receptor α (ERRα) functions in the hypoxic injury of microglial cells
2022
Deng, Chao-Yang | Zhu, Ting-Ting | Lian, Shuai | Wang, Jian-Fa | Wu, Rui | Zheng, Jia-San
Hypoxia is a common pathological condition after spinal cord injury. Oestrogen-related receptor alpha (ERRα), as a key regulator of energy metabolism and mitochondrial functions, plays an important role in maintaining cell homeostasis. However, its role in hypoxic spinal microglia has not been fully elaborated. This study investigated the receptor’s activity when these cells are hypoxic and used as an in vitro model. In this study, microglia (BV2) were exposed to cobalt chloride as a hypoxic model, and the inverse agonist of ERRα, XCT790, and pyrido[1,2-α]-pyrimidin-4-one were used to regulate the expression of the receptor to explore the ERRα-related mechanisms involved in hypoxic spinal cord injury (SCI). ERRα promoted autophagy in BV2 cells and inhibited the activation of the p38 mitogen-activated protein kinase (MAPK) pathway and the expression of anti-inflammatory factors under hypoxic conditions. It also promoted the expression of fibronectin type III domain containing protein 5 (FNDC5). When a hypoxic SCI occurs, ERRα may maintain the homeostasis of spinal cord nerve cells by regulating autophagy and the p38MAPK/nuclear factor-kappa B cell and FNDC5/brain-derived neurotrophic factor signalling pathways, which are beneficial to the recovery of these cells.
Afficher plus [+] Moins [-]Modulators of KATP channels in the prevention of oxidative stress and antioxidant capacity improvement in the rat heart with different resistance to hypoxia upon cobalt treatment
2016
Kurhaluk, Natalia | Tkachenko, Halyna
Introduction: The main goal of the study was to investigate the effect of KATP channel modulators on development of oxidative stress in the heart of rats showing different resistance to hypoxia.Material and Methods: The study has been performed on rats showing high- (HR) or low-resistance (LR) to hypoxia under modulators of ATP-sensitive potassium (KATP) channel opener pinacidil (0.06 mg/kg) and blocker glibenclamide (1 mg/kg) upon cobalt (Co) treatment (30 mg of cobalt chloride/kg b.w., 3 h). Changes in the oxidative stress parameters of the heart tissue, such as lipid peroxidation (LPO), level of oxidatively modified protein (OMP), and antioxidant defence system (superoxide dismutase - SOD, catalase -CAT, glutathione peroxidase - GPx, glutathione reductase - GR) as well as total antioxidant activity (TAA) were analysed.Results: Co treatment caused a significant decrease in SOD and CAT activity in the heart of LR rats and GPx activity in HR rats. It also led to a decrease in OMP level in the heart of rats with HR in comparison with controls.Conclusion: The obtained results suggest that individual resistance to hypoxia plays a crucial role in Co actions and provides evidence that the effects of KATP channel opener pinacidil in the heart are mediated through different pathways of the antioxidative system, depending on the individual resistance to hypoxia. Pinacidil exerts a protective effect on the heart tissue by preventing the LPO decrease and significantly reducing OMP levels, as well as increasing TTA in rats with LR.
Afficher plus [+] Moins [-]Comparison of a barium chloride test with ELISA for pregnancy detection in cows
2020
Dana, Omer Ismaeel | Ghaidan, Mnnat Talib | Mukhtar, Rafiq Hamakarim | Dyary, Hiewa Othman
Early detection of pregnancy is vital for appropriate reproductive management programmes to facilitate the rapid re-insemination of non-pregnant females and reduce the calving interval. A barium chloride test was compared with a commercial progesterone ELISA to detect pregnancy in non-descriptive cows and investigate if it could be applied as an alternative to ELISA in the field. Blood and urine samples were collected from 74 cows with recorded insemination dates. The progesterone ELISA and barium chloride assay were implemented to detect progesterone (P4) in blood and urine specimens, respectively. The cows' reproductive systems were examined after they were slaughtered to determine the uterus's status. Macroscopic examination of the uterus was used as a reference standard for both tests. The sensitivity rates of the P4 ELISA and barium chloride test to detect pregnant cows were 100.0% and 79.4%, and to detect the corpus luteum (CL) were 83.0% and 87.0%, respectively, their sensitivity increasing in the presence of the CL. The ELISA and barium chloride tests were 79.7% and 52.7% accurate in the diagnosis of pregnancy. The accuracy of the barium chloride test in CL detection increased to 81.0%, and that of the ELISA to 86.4%. There were no significant differences (P = 0.052) between the barium chloride assay and ELISA when they were utilised for the identification of the CL. The barium chloride test can be an inexpensive and time-saving alternative to ELISA in pregnancy diagnosis when the insemination date is known.
Afficher plus [+] Moins [-]Comparison of the bacteriostatic effects of quaternary ammonium compounds and their combinations on a dairy farm environment and the microbial contamination of dairy products
2021
Chen, Nannan | Liu, Shanshan | Liu, Yu | Bai, Tongtong | Jia, Lihua | Wang, Li | Yue, Shan | Wu, Chenhua | Huang, Wenjing | Gao, Li | Fu, Jinlei | Liu, Siyu | Zhao, Tong | Li, Juan | Zhang, Yuntao | Zhu, Zhanbo
Disinfection is key for controlling microbial contamination and ensuring the safe production of milk and dairy products. In this study, we developed a new disinfection method using quaternary ammonium surfactant N-dodecyl-2-(pyridin-1-yl) acetamide chloride as the main component to form a bactericidal complex with either chlorhexidine acetate or glutaraldehyde, and we evaluated the bactericidal effects, safety, and clinical application value of the compound disinfectants. An in vivo acute oral toxicity assay in mice showed an LD50 > 5000 mg/kg body weight without abnormality in pathological tissue sections. Comparison with commercially available products also showed that they have outstanding bactericidal effects. Clinical trials proved that the compound disinfectants have excellent bactericidal effects on the air and ground of the dairy farm and on the skin of cattle, especially in a dairy farm environment. Our findings confirm that the new compound disinfectants have excellent bactericidal performance and are safe to use as disinfectants to prevent mastitis and contamination of the cattle farm environment.
Afficher plus [+] Moins [-]Maternal and fetal arterial blood gas data in normotensive, singleton, isoflurane anesthetized sheep at 124-126 days of gestation
2017
Loughran, C. M. | Kemp, M. W. | Musk, G. C.
The aim of this case series was to describe the differences between maternal and fetal blood-gas results during anesthesia. Sixteen singleton adult merino ewes weighing 60.1 ± 5.1 kg at 125.7 d (124 to 126 d) gestation were anesthetized. Maternal (radial) and fetal (umbilical) arterial blood gas samples were collected 79 ± 6 min after the start of anesthesia if maternal mean arterial pressure (MAP) was stable and > 65 mmHg. Fetal pH, partial arterial pressure of oxygen (PaO2), glucose, arterial hemoglobin oxygen saturation (SaO2), sodium, and chloride were significantly lower and fetal partial arterial pressure of carbon dioxide (PaCO2), lactate, hematocrit, total hemoglobin, potassium, and calcium were significantly higher than maternal blood-gas values. Fetal pH, PaO2, and BE were lower and fetal lactate was higher than fetal umbilical arterial samples previously reported, which may indicate a non-reassuring fetal status. Further refinement of the ovine experimental model is warranted with fetal monitoring during maternal anesthesia.
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