Arginase activity patterns and their regulation during embryonic development in liver and kidney

1973 ◽  
Vol 33 (1) ◽  
pp. 1-17 ◽  
Author(s):  
Matthews O. Bradley
Keyword(s):  
Embryonic Development ◽  
Activity Patterns ◽  
Arginase Activity ◽  
Liver And Kidney

scholarly journals Evaluation of optimal conditions for arginase activity in streptozotocin induced diabetic rats

2012 ◽  
Vol 50 (No. 2) ◽  
pp. 69-76 ◽  
Author(s):  
M. Erisir ◽  
E. Ercel ◽  
S. Yilmaz ◽  
S. Ozan
Keyword(s):  
Maximal Activity ◽  
Diabetic Rats ◽  
Arginase Activity ◽  
Female Rats ◽  
Kinetic Properties ◽  
Ph Profile ◽  
Optimum Ph ◽  
Liver And Kidney ◽  
And Control ◽  
Assay Conditions

The assay conditions needed to achieve maximal activity of liver and kidney arginase in diabetic and non-diabetic rats were investigated and compared. The physicochemical and kinetic properties of liver arginase in diabetic and control rats were very similar, those of kidney arginase were significantly different. It was found that preincubation temperature (68&deg;C), preincubation period (20 min), optimum pH (10.1) of liver arginase and K<sub>m</sub> (3.2) for its substrate, L-arginine, did not change in diabetic and non-diabetic rats. As a consequence of diabetes, the optimum Mn<sup>2+</sup> concentration for liver arginase only changed from 1 to 2 mM. Although the preincubation temperature and period for activation of kidney arginase in control rats was unnecessary, they were found to be 56&ordm;C and 12 min in diabetic rats. The pH profile of arginase in kidney of diabetic rats was different from that of control rats. The K<sub>m</sub> value (6.7) of arginase for L-arginine in kidney is unchanged in diabetes whereas a marked decrease in V<sub>max</sub> was found. Optimum Mn<sup>2+</sup> concentration (2 mM) for kidney arginase was unchanged in diabetes. The activity of arginase in liver of diabetic animals was higher 1.5 to 1.7 times than that of controls. Diabetes caused an about 53% decrease of arginase activity in kidney of female rats, 26% in that of males. These findings may suggest an idea that encoded arginases by separate gene loci may be affected differently by the pathological and hormonal status.

scholarly journals Molecular charcteristics of chicken kidney arginase

1975 ◽  
Vol 145 (2) ◽  
pp. 153-157 ◽  
Author(s):  
S Traniello ◽  
R Barsacchi ◽  
E Magri ◽  
E Grazi
Keyword(s):  
Substrate Specificity ◽  
Arginase Activity ◽  
Chicken Liver ◽  
Mitochondrial Matrix ◽  
The Matrix ◽  
Liver And Kidney ◽  
Rate Of Hydrolysis ◽  
Chicken Kidney ◽  
Hydrolysis Of ◽  
Regulatory Significance

Chicken kidney contains two arginases with different sedimentation coefficients and substrate specificity. The ligher of these arginases, which hydrolyses only L-arginine, has been purified about 3000-fold. Like the “ureotelic” arginase, developed in chicken liver after starvation, it displays many of the properties of the arginase of the “ureotelic” species. This seems to exclude the possibility that ureotelism and uricotelism are characterized by a specific type of arginases. Both liver and kidney arginases are located in the mitochondrial matrix. The rate of hydrolysis of arginine thus not only depends on the arginase activity but also on the rate of transport of arginine into the matrix. This last process therefore is of regulatory significance.

Acetaminophen: Neonatal hepatotoxicity due to late pregnancy exposure

1987 ◽  
Vol 45 ◽  
pp. 718-719
Author(s):  
G.A. Miranda ◽  
M.A. Arroyo ◽  
C.A. Lucio ◽  
M. Mongeotti ◽  
S.S. Poolsawat
Keyword(s):  
Low Dose ◽  
Fetal Liver ◽  
Late Pregnancy ◽  
Toxic Chemicals ◽  
Control Group ◽  
High Dose ◽  
Over The Counter ◽  
Liver And Kidney ◽  
Neonatal Liver ◽  
Childbearing Women

Exposure to drugs and toxic chemicals, during late pregnancy, is a common occurrence in childbearing women. Some studies have reported that more than 90% of pregnant women use at least 1 prescription; of this, 60% used more than one. Another study indicated that 80% of the consumed drugs were not prescribed, and of this figure, 95% were “over-the-counter” drugs. Acetaminophen, the safest of all over-the-counter drugs, has been reported to induce fetal liver necrosis in man and animals and to have abortifacient and embryocidal action in mice. This study examines the degree to which acetaminophen affects the neonatal liver and kidney, when a fatty diet is simultaneously fed to the mother during late pregnancy.Timed Swiss Webster female mice were gavaged during late pregnancy (days 16-19) with fat suspended acetaminophen at a high dose, HD = 84.50 mg/kg, and a low dose, LD = 42.25 mg/kg; a control group received fat alone.

Predicting spatial activity patterns in a neural map from a probabilistic atlas of 3-D reconstructed neurons

1995 ◽  
Vol 53 ◽  
pp. 812-813
Author(s):  
G. Jacobs ◽  
F. Theunissen
Keyword(s):  
Activity Patterns ◽  
Three Dimensional ◽  
Sensory System ◽  
Neural System ◽  
Probabilistic Atlas ◽  
Uniform Sample ◽  
Dimensional Reconstruction ◽  
The Time Domain ◽  
And Function ◽  
Visualization Techniques

In order to understand how the algorithms underlying neural computation are implemented within any neural system, it is necessary to understand details of the anatomy, physiology and global organization of the neurons from which the system is constructed. Information is represented in neural systems by patterns of activity that vary in both their spatial extent and in the time domain. One of the great challenges to microscopists is to devise methods for imaging these patterns of activity and to correlate them with the underlying neuroanatomy and physiology. We have addressed this problem by using a combination of three dimensional reconstruction techniques, quantitative analysis and computer visualization techniques to build a probabilistic atlas of a neural map in an insect sensory system. The principal goal of this study was to derive a quantitative representation of the map, based on a uniform sample of afferents that was of sufficient size to allow statistically meaningful analyses of the relationships between structure and function.

Mitochondrial Oxidation of p-N, N-Dimethylamino-β-Phenethylamine (DAPA)

1975 ◽  
Vol 33 ◽  
pp. 458-459
Author(s):  
W. Allen Shannon ◽  
Hannah L. Wasserkrug ◽  
andArnold M. Seligman
Keyword(s):  
Guinea Pig ◽  
Oxidase Activity ◽  
Amine Oxidase ◽  
Histochemical Demonstration ◽  
Guinea Pig Heart ◽  
Pig Kidney ◽  
Cytoplasmic Vacuoles ◽  
Liver And Kidney ◽  
Mitochondrial Oxidation ◽  
Amine Oxidase Activity

The synthesis of a new substrate, p-N,N-dimethylamino-β-phenethylamine (DAPA)3 (Fig. 1) (1,2), and the testing of it as a possible substrate for tissue amine oxidase activity have resulted in the ultracytochemical localization of enzyme oxidase activity referred to as DAPA oxidase (DAPAO). DAPA was designed with the goal of providing an amine that would yield on oxidation a stronger reducing aldehyde than does tryptamine in the histochemical demonstration of monoamine oxidase (MAO) with tetrazolium salts.Ultracytochemical preparations of guinea pig heart, liver and kidney and rat heart and liver were studied. Guinea pig kidney, known to exhibit high levels of MAO, appeared the most reactive of the tissues studied. DAPAO reaction product appears primarily in mitochondrial outer compartments and cristae (Figs. 2-4). Reaction product is also localized in endoplasmic reticulum, cytoplasmic vacuoles and nuclear envelopes (Figs. 2 and 3) and in the sarcoplasmic reticulum of heart.

Live Confocal Analysis of Fertilization and Early Development

2001 ◽  
Vol 7 (S2) ◽  
pp. 1012-1013
Author(s):  
Uyen Tram ◽  
William Sullivan
Keyword(s):  
Drosophila Melanogaster ◽  
Embryonic Development ◽  
Real Time ◽  
Early Development ◽  
Fluorescent Probes ◽  
Primary Defect ◽  
Fluorescent Analysis ◽  
Dynamic Event ◽  
Enormous Amount ◽  
Fluorescent Studies

Embryonic development is a dynamic event and is best studied in live animals in real time. Much of our knowledge of the early events of embryogenesis, however, comes from immunofluourescent analysis of fixed embryos. While these studies provide an enormous amount of information about the organization of different structures during development, they can give only a static glimpse of a very dynamic event. More recently real-time fluorescent studies of living embryos have become much more routine and have given new insights to how different structures and organelles (chromosomes, centrosomes, cytoskeleton, etc.) are coordinately regulated. This is in large part due to the development of commercially available fluorescent probes, GFP technology, and newly developed sensitive fluorescent microscopes. For example, live confocal fluorescent analysis proved essential in determining the primary defect in mutations that disrupt early nuclear divisions in Drosophila melanogaster. For organisms in which GPF transgenics is not available, fluorescent probes that label DNA, microtubules, and actin are available for microinjection.

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