Deep hypothermia impact on acid–base parameters and liver antioxidant status in an in vivo rat model

2009 ◽  
Vol 87 (6) ◽  
pp. 471-478 ◽  
Author(s):  
Norma Alva ◽  
Teresa Carbonell ◽  
Jesús Palomeque

Although clinical hypothermia is used for reducing postischemic damage, injurious effects have also been reported. To determine whether hypoxia and oxidative stress are induced by systemic deep hypothermia, we used an in vivo rat model keeping the arterial Pco2constant. Animals were divided into 4 groups: sham, 2 h deep hypothermia (21 °C), 1 h posthypothermia (rewarmed to 37 °C after 2 h deep hypothermia), and 3 h normothermia. Blood gases, portal vein blood flow, arterial pressure, and heart rate were monitored throughout the experiment. Liver enzyme antioxidant activity was also examined. The hemodynamic parameters decreased drastically during hypothermia, but were fully restored after rewarming. No changes in hepatic antioxidant activity (catalase, glutathione peroxidase, and superoxide dismutase) were observed. The redox level in liver (GSH/GSSG ratio) was preserved in hypothermia but decreased when animals were rewarmed. ALT did not increase and no evidence of tissue hypoxia was detected in liver regarding the restricted flow during hypothermia. With the described protocol, deep hypothermia is regarded as an experimental safe model.

1990 ◽  
Vol 258 (1) ◽  
pp. F69-F74 ◽  
Author(s):  
R. T. Kunau ◽  
K. A. Walker

The present studies examined the effect of three-fourths nephrectomy on the rate of acidification, i.e., total CO2 (tCO2) absorption (JtCO2) in the superficial distal tubule of the rat. Total glomerular filtration rate following three-fourths nephrectomy was 1.29 +/- 0.06 vs. 3.29 +/- 0.08 ml/min in sham controls, P less than 0.001. Systemic acid-base parameters were the same in both groups, but urine pH was lower in nephrectomized rats. In vivo microperfusion with identical isohydric solutions revealed that the JtCO2, fluid absorption (Jv), lumen-negative transepithelial potential difference (VT) were all significantly greater in the distal tubule of remnant kidneys. As the relative increase in Jv exceeded JtCO2, the perfusate tCO2 concentration increased markedly in remnant kidney distal tubules from 30.3 +/- 0.59 to 39.9 +/- 1.73 mM. To determine if the increase in tCO2 concentration accounted for the difference in JtCO2, a second control group was studied using a perfusate tCO2 concentration of 39.6 +/- 0.79 mM. Distal tubular JtCO2, Jv, and VT were significantly less in this control group than in the remnant kidney group. In separate studies, 10(-4) M amiloride was added to the perfusate used in remnant kidneys and controls studied with the elevated perfusate tCO2 concentration. The addition of 10(-4) M amiloride to the perfusate reduced VT and JtCO2. At identical values for VT, JtCO2 was higher in the distal tubule of remnant kidneys than in controls. We conclude the following. 1) The rate of acidification is increased in the distal tubule of remnant kidneys.(ABSTRACT TRUNCATED AT 250 WORDS)


2020 ◽  
Vol 37 (10) ◽  
pp. 1755-1764
Author(s):  
Luana Schmidt ◽  
Natália de Vargas Heck ◽  
Ingrid Ferreira ◽  
Gabriela Göethel ◽  
Sabrina Somacal ◽  
...  

2021 ◽  
Vol 12 ◽  
Author(s):  
Jichao Li ◽  
Zeng Zhang ◽  
Jinan Qiu ◽  
Xiaohan Huang

Osteoarthritis (OA) is mainly manifested by joint pain, stiffness and mobility disorder, which is the main cause of pain and disability in middle-aged and elderly people. In this study, we aimed to explore the role and mechanism of 8-Methoxypsoralen (8-MOP) in the OA model both in vitro and in vivo. The rat chondrocytes were treated with IL-1β, and the proliferation, apoptosis, inflammatory reactions and oxidative stress responses were determined after treatment with different concentrations of 8-MOP. Real-time quantitative polymerase chain reaction (qRT-PCR) and/or Western blot were implemented to check the AMPK/SIRT1/NF-κB expression in chondrocytes. The NF-κB activity was determined by dual luciferase experiment. The pain threshold of OA rat model dealt with 8-MOP and/or the SIRT1 inhibitor EX527 was measured. Our results revealed that 8-MOP evidently reduced IL-1β-mediated apoptosis and inhibition of proliferation, and mitigated the expression of inflammatory cytokines and oxidative stress factors in chondrocytes. Additionally, 8-MOP promoted phosphorylated level of AMPKα, enhanced SIRT1 expression and inhibited the phosphorylation of NF-κB. After treatment with EX527, 8-MOP-mediated protective effects on chondrocytes were mostly reversed. In vivo, 8-MOP obviously improved the pain threshold in the OA rat model and reduced the injury and apoptosis of chondrocytes in the joints. In addition, 8-MOP relieved inflammatory and oxidative stress responses in the articular cartilage via enhancing SIRT1 and repressing NF-κB activation. After the treatment with EX527, the 8-MOP-mediated protective effects were distinctly weakened. In summary, our study testified that 8-MOP alleviates pain, inflammatory and oxidative stress responses in OA rats through the SIRT1/NF-κB pathway, which is expected to become a new reagent for clinical treatment of OA.


2021 ◽  
Author(s):  
Omer F. Gungor ◽  
Saleh Salman ◽  
Saurav Ranjitkar ◽  
Delong Zhang ◽  
Xiuchun (Cindy) Tian

Abstract Follicular fluid is the microenvironment that supports oocyte maturation and competence. Using Abbott iSTAT1™ and NanoDrop, we determined the dynamics of acid-base, electrolyte, metabolites, and total protein in venous blood, fluids of the dominant follicle (FF), oviduct (OF), and uterus (UF) during the window of oocyte maturation. Holstein heifers (n=36) were synchronized with PGF2α on Days -11 and 0, CIDR during Days -6 to 1, and GnRH given on Day 2 after 2nd PG. Samples were collected at 24h, 48h, 60h, 72h, and 78h after 2nd PG. Most electrolytes analyzed, Cl-, K+, and Ca2+ were significantly affected in blood and FF (P<0.05) by CIDR removal. Similarly, Cl- and Na+ also significantly changed in OF and UF across time. Glucose, lactate, and creatinine significantly changed across time points in FF compared to blood. Moreover, pO2, pCO2, TCO2, and pH significantly changed across time in FF. Most parameters were not significantly correlated between blood and FF across time points except for glucose, Cl- and creatinine. Furthermore, pO2 in FF was nearly 3X higher than blood, suggesting low O2 during in vitro maturation is inappropriate. In conclusion, components of the follicular fluid undergo major changes during the window of oocyte maturation.


2021 ◽  
pp. 48-51
Author(s):  
Balbinder Kumar ◽  
Ganesh Narayan Jha ◽  
Debarshi Jana

Aim of the study role of acid base balance in chronic severe anaemic patients admitted in Department of Medicine, Darbhanga Medical College and Hospital, Laheriasarai, Bihar. Study subject include 50 chronic and severe anaemic patients. All the fty cases underwent detailed haematological, biochemical, electrocardiographic, roentgenographic studies followed by extensive analysis of blood for blood gases and acid base parameters at the onset. Some were further studied for venous blood lactate and the effect of intravenous frusemide on the acid base parameters and the clinical state of the patient. Twenty normal controls were also studied. Work in future on the problem of chronic severe anaemia should include cases with cardiac failure and other complications like respiratory infections etc. and they should be studied for myocardial function, glomerular ltration rate and renal anion transport in addition to blood gases and acid base study as done by us. The role of ionotropic agents should be studied in such cases in isolation from that with diuretics. The administration of oxygen alone with a mask is also expected to improve almost all parameters quickly and should be studied.


2005 ◽  
Vol 25 (1_suppl) ◽  
pp. S392-S392
Author(s):  
Nadja Van Camp ◽  
Koen Van Laere ◽  
Ruth Vreys ◽  
Marleen Verhoye ◽  
Erwin Lauwers ◽  
...  

Planta Medica ◽  
2014 ◽  
Vol 80 (16) ◽  
Author(s):  
A Vora ◽  
V Londhe ◽  
N Pandita

1992 ◽  
Vol 67 (03) ◽  
pp. 366-370 ◽  
Author(s):  
Katsuhiko Nawa ◽  
Teru Itani ◽  
Mayumi Ono ◽  
Katsu-ichi Sakano ◽  
Yasumasa Marumoto ◽  
...  

SummaryPrevious studies on recombinant human soluble thrombomodulin (rsTM) from Chinese hamster ovary cells revealed that rsTM was expressed as two proteins that differed functionally in vitro due to the presence (rsTMp) or absence (rsTMa) of chondroitin-4-sulfate. The current study evaluates the in vivo behavior of rsTM in rats and in a rat model of tissue factor-induced disseminated intravascular coagulation (DIC). rsTMp was more potent than rsTMa for prolongation of the activated partial thromboplastin time (APTT) and their in vivo half-lives determined by ELISA were 20 min for rsTMp and 5.0 h for rsTMa. Injection of a tissue factor suspension (5 mg/kg) resulted in DIC as judged by decreased platelet counts and fibrinogen concentrations, prolonged APTT, and increased fibrin and fibrinogen degradation products (FDP) levels. A bolus injection of either rsTM (0.2 mg/kg) 1 min before induction of DIC essentially neutralized effects on platelets, fibrinogen, and FDP levels, and had only a moderate effect on APTT prolongation. The dose of anticoagulant to inhibit the drop in platelet counts by 50% (ED50) was 0.2 mg/kg rsTMa, 0.07 mg/kg rsTMp, and 7 U/ kg heparin. The effect of increasing concentrations of rsTM and heparin on bleeding times were compared in experiments involving incision of the rat tail. Doubling of the bleeding times occurred at 5 mg/kg rsTMa, 3 mg/kg rsTMp or 90 U/kg heparin. These values represent a 25-fold increase over the ED50 for rsTMa, 43-fold for rsTMp and 13-fold for heparin. These results suggest that rsTMp is a potent anticoagulant to inhibit the platelet reduction when injected prior to the induction of DIC in rats.


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