scholarly journals Acetazolamide-insensitive carbonic anhydrase activities in liver and tonic skeletal muscle of adult male rats with streptozotocin-induced diabetes mellitus

1990 ◽  
Vol 272 (2) ◽  
pp. 553-556 ◽  
Author(s):  
J B Moynihan ◽  
S Ennis

One of the four discrete isoenzymes of carbonic anhydrase hitherto characterized, CA III, has the lowest turnover rate and the greatest resistance to inhibition by sulphonamides. Streptozotocin-induced diabetes mellitus resulted in a reduction in acetazolamide-resistant activity of carbonic anhydrase in the liver, but not in tonic skeletal muscle, of adult male rats. The hepatic activity declined with apparent first-order kinetics [calculated rate constant (k) 0.089 day-1] to a minimum of approx. 6% of control values; the reduction in activity was moderated by administration of insulin.

2006 ◽  
Vol 71 (3) ◽  
pp. 411-422 ◽  
Author(s):  
David Havlíček ◽  
Libor Turek ◽  
Jiří Plocek ◽  
Zdeněk Mička

Solubility in the (Me4N)2SeO4-H2SeO4-H2O and (Me4N)2SeO4-Li2SeO4-H2O systems were studied. The new compounds, tetramethylammonium hydrogenselenate monohydrate ((Me4N)HSeO4·H2O) and lithium tetramethylammonium selenate tetrahydrate (Li(Me4N)SeO4·4H2O), have been found in these systems. Both substances were characterised by chemical analysis and IR molecular spectroscopy. Both of the title substances decompose under the influence of X-radiation and, thus, their structures cannot be determined. The radiolysis of both substances was studied in greater detail. Tetramethylammonium hydrogenselenate monohydrate is dehydrated by X-radiation to form the anhydrous salt. The reaction is controlled by first-order kinetics with a rate constant of 1.30(3) × 10-3 s-1.


2021 ◽  
Author(s):  
Amany Mohamed Shalaby ◽  
Adel Mohamed Aboregela ◽  
Mohamed Ali Alabiad ◽  
Mona Tayssir Sadek

Abstract Diabetes mellitus (DM) represents a widespread metabolic disease with a well-known neurotoxicity in both central and peripheral nervous systems. Oxymatrine is a traditional Chinese herbal medicine that has various pharmacological activities including; anti-oxidant, anti-apoptotic and anti-inflammatory potentials. The present work aimed to study the impact of diabetes mellitus on the cerebellar cortex of adult male albino rat and to evaluate the potential protective role of oxymatrine using different histological methods. Fifty-five adult male rats were randomly divided into three groups: group I served as control, group II was given oxymatrine (80 mg/kg/day) orally for 8 weeks and group III was given a single dose of streptozotocin (50mg/kg) intaperitoneally to induce diabetes. Then diabetic rats were subdivided into two subgroups: subgroup IIIa that received no additional treatment and subgroup IIIb that received oxymatrine similar to group II. The diabetic group revealed numerous changes in the Purkinje cell layer in the form of multilayer arrangement of Purkinje cells, shrunken cells with deeply stained nuclei as well as focal loss of the Purkinje cells. A significant increment in GFAP and synaptophysin expression was reported. Transmission electron microscopy showed irregularity and splitting of myelin sheaths in the molecular layer, dark shrunken Purkinje cells with ill-defined nuclei, dilated Golgi saccules and dense granule cells with irregular nuclear outlines in the granular layer. In contrast, these changes were less evident in diabetic rats that received oxymatrine. In conclusion, Oxymatrine could protect the cerebellar cortex against changes induced by DM.


2012 ◽  
Vol 65 (11) ◽  
pp. 1970-1974 ◽  
Author(s):  
C. Y. Kuo ◽  
C. Y. Pai ◽  
C. H. Wu ◽  
M. Y. Jian

This study applies photo-Fenton and photo-Fenton-like systems to decolorize C.I. Reactive Red 2 (RR2). The oxidants were H2O2 and Na2S2O8; Fe2+, Fe3+, and Co2+ were used to activate these two oxidants. The effects of oxidant concentration (0.3–2 mmol/L) and temperature (25–55 °C) on decolorization efficiency of the photo-Fenton and photo-Fenton-like systems were determined. The decolorization rate constants (k) of RR2 in the tested systems are consistent with pseudo-first-order kinetics. The rate constant increased as oxidant concentration and temperature increased. Activation energies of RR2 decolorization in the UV/H2O2/Fe2+, UV/H2O2/Fe3+, UV/Na2S2O8/Fe2+ and UV/Na2S2O8/Fe3+ systems were 32.20, 39.54, 35.54, and 51.75 kJ/mol, respectively.


1978 ◽  
Vol 176 (3) ◽  
pp. 677-681 ◽  
Author(s):  
Peggy R. Borum

Diabetes, starvation and various hormonal treatments are known to alter drastically carnitine concentrations in the body. Before the mechanisms controlling carnitine metabolism could be determined, it was necessary to establish normal carnitine concentrations in both sexes at different ages. Carnitine was assayed in plasma, liver, heart and skeletal muscle of rats from birth to weaning. The plasma carnitine increased rapidly during the first 2 days after birth. Carnitine in both heart and skeletal muscle increased, whereas liver concentrations declined during the first week of life. A carnitine-free diet containing sufficient precursors for carnitine biosynthesis was fed to weanling rats. Groups of ten male and ten female rats were killed each week for 10 consecutive weeks. Carnitine was determined in plasma, liver, heart, skeletal muscle, urine and epididymis in the male. There was no difference in carnitine concentrations between the sexes at weaning. Plasma, heart and muscle concentrations were higher in adult male rats than in adult females. However, liver carnitine and urinary carnitine concentrations were higher in adult female than in adult male rats. The epididymal carnitine concentration increased very rapidly during 50 to 70 days of age and the differences in carnitine concentrations between the sexes also became apparent during this time. Thus both the age and the sex of the human subject or experimental animal must be considered when investigating carnitine metabolism.


2018 ◽  
Vol 32 ◽  
pp. 40
Author(s):  
Slavica Mutavdzin ◽  
Jovana Jakovljevic Uzelac ◽  
Jovan Despotovic ◽  
Sanja Stankovic ◽  
Milica Labudovic Borovic ◽  
...  

Author(s):  
А.А. Панов ◽  
Е.М. Ржавина ◽  
М.П. Морозова ◽  
А.К. Ердяков ◽  
С.А. Гаврилова

Цель исследования - изучение динамики морфологических изменений роговицы и заднего отдела глаза крыс при длительной гипергликемии. Методика. Исследование выполнено на 36 самцах крыс Wistar. Сахарный диабет индуцировали внутрибрюшинной инъекцией стрептозотоцина (65 мг/кг), после чего ежедневно вводили подкожно малые дозы инсулина (2 ЕД/кг). На 50-е, 58-е и 66-е сут эксперимента производили энуклеацию глаз у глубоко наркотизированных животных. Гистологические срезы фрагментов глаз окрашивали гематоксилин-эозином, проводили морфометрию параметров роговицы и сетчатки. Результаты. Средняя концентрация глюкозы и кетоновых тел крови в группе сахарного диабета составила 29,8 ммоль/л и 0,889 ммоль/л, в контрольной группе - 6,2 ммоль/л и 0,847 ммоль/л соответственно. Анализ гистологических срезов глаз выявил признаки отека роговицы, хориоидеи и наружных слоев центральных отделов сетчатки до появления других качественных и количественных морфологических изменений. Заключение. Оценка толщины роговицы, хориоидеи и наружных слоев центральных отделов сетчатки может служить предиктором развития диабетической ретинопатии. The aim was to study morphological changes in the cornea and the posterior part of rat eye during prolonged hyperglycemia. Methods. The study was performed on 36 Wistar male rats. Diabetes mellitus was induced by an injection of streptozotocin (65 mg/kg, i.p.) followed by daily injections of low doses of insulin (2 U/kg, s.c.). Eyes were enucleated from deeply anesthetized rats on days 50, 58, and 66 of the experiment. Histologic sections were stained with hematoxylin-eosin, and morphometry of the cornea and the retina was performed. Results. Mean blood concentrations of glucose and ketone bodies were 29.8 mmol/L and 0.889 mmol/L, respectively, in the diabetic group and 6.2 mmol/L and 0.847 mmol/L, respectively, in the control group. The histological analysis revealed signs of edema in the cornea, choroid and outer layers of the central retina, which preceded other morphological changes. Conclusion. Evaluating thickness of the cornea, choroid and outer layers of the central retina may serve for prediction of diabetic retinopathy.


Author(s):  
M.N. Tsitovskyi ◽  
M.V. Logash ◽  
I.I. Savka

According to the World Health Organization, cardiovascular diseases and diabetes mellitus occupy a significant niche in the structure of diseases with high disability and mortality impact and pose major healthcare and social issues. It should be stressed that 50-80% of fatal cases in patients with diabetes are associated with cardiovascular diseases. The purpose of this study is to determine the histostructural characteristics and to perform morphometric analysis of the components of the aortic wall and its hemomicrocirculatory bed of the aorta in 6 and 8 weeks of streptozotocin-induced diabetes mellitus. The material for the histological study included the sections of the wall of the ascending aorta, the aortic arch, and the descending aorta taken from 26 sexually mature white male rats weighing 100 - 160 g. For morphometric examination, a series of photos of the aortic wall was taken using a Meiji MT4300 LED microscope with an x40 objective, x10 ocular. The measurements were carried out using the Image J software. The development of micro - and macroangiopathies in experimental animals with 8-week streptozotocin-induced diabetes mellitus was histologically confirmed. Statistical analysis revealed a significant difference in all morphometric parameters of the components of the aortic wall and the vessels of its hemomicrocirculatory bed after 8 weeks of experimental diabetes as compared with the normal values, control values, and in values obtained at the 6-week period of the experiment. The study has demonstrated clear dependence between the severity of destructive changes in the aortic wall and sections of its hemomicrocirculatory bed and the duration of the experiment.


1994 ◽  
Vol 267 (1) ◽  
pp. E132-E139
Author(s):  
S. S. Kim ◽  
J. W. Bae ◽  
C. Y. Jung

With the use of [3H]leucine pulse-chase and immunoprecipitation methods, we measured the rate of GLUT-4 degradation in rat adipocytes in the steady state at 37 degrees C. We also studied the relationship of the reduced GLUT-4 levels observed in fasted and streptozotocin (STZ)-induced diabetic rats on degradation. GLUT-4 degradation was a simple, first-order decay process. The decay was describable by a single, first-order rate constant (k). A k value of 0.061/h was estimated in control rat adipocytes. In the adipocytes of fasted and STZ-induced diabetic rats, cellular GLUT-4 contents were reduced to 36 and 43% of the control, respectively. The rates of GLUT-4 degradation were also reduced significantly, with kappa values of 0.038 and 0.041/h, respectively. These changes were reversible; the decreased values returned to control values when GLUT-4 contents were normalized by refeeding and insulin injection. These findings demonstrate the presence of a posttranslational mechanism in rat adipocytes that reduces the GLUT-4 degradation rate constant when the cellular GLUT-4 level is reduced by a pretranslational defect.


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