scholarly journals The distinction between γ-glutamylhydroxamate synthetase and l-glutamine–hydroxylamine glutamyltransferase activities in rat tissues. Studies in vivo

1973 ◽  
Vol 133 (1) ◽  
pp. 59-66 ◽  
Author(s):  
Annemarie Herzfeld ◽  
Nathan A. Estes
Keyword(s):  
Tissue Distribution ◽  
Enzyme Activities ◽  
Differential Response ◽  
Rat Tissues ◽  
Synthetase Activity ◽  
Assay Condition ◽  
Foetal Liver ◽  
Males And Females ◽  
Neonatal Kidney

The formation of γ-glutamylhydroxamate by homogenates under optimum assay condition showed an inconstancy in the ratios of the enzyme activities utilizing l-glutamate and ATP (γ-glutamylhydroxamate synthetase) and l-glutamine and ADP (l-glutamine–hydroxylamine glutamyltransferase) in a number of normal and neoplastic rat tissues. Although γ-glutamylhydroxamate synthetase activities in adult livers and kidneys were identical in males and females, l-glutamine–hydroxylamine glutamyltransferase activities in the organs of females were significantly lower. The developmental formations of the two activities in liver, kidney, brain and muscle were not simultaneous. The l-glutamine–hydroxylamine glutamyltransferase activity in foetal liver or neonatal kidney could be prematurely evoked by thyroxine, but the γ-glutamylhydroxamate synthetase activity remained unchanged. Injections of cortisol also had dissimilar effects on the two activities in thymus and hepatomas. The discrepant tissue distribution, asynchronous developmental formation and differential response to several hormonal stimuli provide evidence in vivo that the two activities are not catalysed by the same protein.

Tissue distribution of sulfolipids in the rat. Restricted location of sulfatoxygalactosylacylalkylglyerol

1981 ◽  
Vol 59 (7) ◽  
pp. 556-563 ◽  
Author(s):  
Clifford Lingwood ◽  
Genevieve Hay ◽  
Harry Schachter
Keyword(s):  
Tissue Distribution ◽  
Indirect Immunofluorescence ◽  
Rat Tissues ◽  
Tissue Sections ◽  
Frozen Tissue

Eleven rat tissues (excluding brain) have been assayed for their ability to synthesize sulfatoxygalactosylacylalkylglycerol (SGG) from Na235SO4in vivo. These tissues were also assayed for the presence of SGG by an indirect immunofluorescence procedure using rabbit anti-SGG and frozen tissue sections. By both procedures SGG was found to be restricted to the testis; several novel sulfolipids were detected during this study.

scholarly journals The Tissue Distribution of Four Major Coumarins after Oral Administration of Angelicae Pubescentis Radix Extract to Rats Using Ultra-High-Performance Liquid Chromatography

2019 ◽  
Vol 2019 ◽  
pp. 1-8 ◽  
Author(s):  
Yuanyuan Ge ◽  
Shujing Chen ◽  
Qian Luo ◽  
Chun-peng Wang ◽  
Jia Hao ◽  
...  
Keyword(s):  
Liquid Chromatography ◽  
Oral Administration ◽  
Tissue Distribution ◽  
High Performance ◽  
Ultra Performance Liquid Chromatography ◽  
Tissue Homogenate ◽  
Rat Tissues ◽  
Relative Standard ◽  
Limit Of Quantitation

Angelicae pubescentis radix (APR) is widely applied in treating rheumatoid arthritis in China. Coumarins are the major active compounds of APR extract including columbianetin, columbianetin acetate, osthole, and columbianadin. The in vivo behavior of the four major coumarins of APR has not been systematically reported. A feasible and reliable ultra-performance liquid chromatography (UPLC) method was established and validated for the quantification of the above four coumarins in rat various tissues (including heart, liver, spleen, lung, kidney, uterus, ovary, and muscle) after oral administration of APR extract. The separation was implemented on a Waters ACQUITY BEH C18 column (4.6 mm × 100 mm, 1.7 μm) with gradient mobile phase comprising acetonitrile-water (with 1mM formic acid) at a flow rate of 0.3 mL/min. The tissue homogenate samples were prepared by liquid-liquid extraction with ethyl acetate. The calibration curves were linear in the range of 1.6-20000 ng/mL for four coumarins with the lower limit of quantitation of 1.6 ng/mL in rat tissues. The intraday and interday precisions and recoveries were all within 80-100% with the relative standard deviations (RSDs) which were all less than 10.9%. The method was successfully applied to the tissue distribution research after oral administration of 6.0 g/kg APR extract to rat. The results revealed that the tissues distributions of four coumarins were in the liver, followed by the ovary, uterus, kidney, lung, heart, spleen, and muscle.

scholarly journals DEVELOPMENTAL STUDIES ON GLYOXYSOMES IN RICINUS ENDOSPERM

1970 ◽  
Vol 44 (1) ◽  
pp. 94-102 ◽  
Author(s):  
B. P. Gerhardt ◽  
Harry Beevers
Keyword(s):  
Enzyme Activities ◽  
Isocitrate Lyase ◽  
Total Activity ◽  
Early Growth ◽  
Soluble Form ◽  
Synthetase Activity ◽  
Developmental Studies ◽  
Lyase Activity ◽  
Specific Activities

The development of glyoxysomes and their associated enzymes, isocitrate lyase and malate synthetase, was studied in the endosperm of castor bean seeds during germination and early growth in darkness. The protein content of the glyoxysome fraction, separated by sucrose density centrifugation, increased linearly from day 2 to day 4 and declined subsequently, while maximum enzyme activities were reached at day 5. The specific activities of the enzymes in the glyoxysomes increased until day 5 and remained constant thereafter. At all stages of germination the only organelle with isocitrate lyase activity was the glyoxysome, but at the earlier stages a greater portion of the total activity was recovered in the soluble form. Malate synthetase was found primarily in the glyoxysomes after day 4, but at earlier stages part of the activity appeared at regions of lower density on the sucrose gradient. It was shown that this particulate malate synthetase activity was due to glyoxysomes broken during preparation, and that, as a result of this breakage, isocitrate lyase was solubilized. We conclude that both enzymes are housed in the glyoxysome in vivo throughout the germination period, and that the rise and fall in enzyme activities in phase with fat breakdown correspond to the net production and destruction of this organelle.

scholarly journals The distinction between γ-glutamylhydroxamate synthetase and l-glutamine–hydroxylamine glutamyltransferase activities in rat tissues. Studies in vitro

1973 ◽  
Vol 133 (1) ◽  
pp. 49-57 ◽  
Author(s):  
Annemarie Herzfeld
Keyword(s):  
Glutamine Synthetase ◽  
Enzyme Activities ◽  
Adenine Nucleotides ◽  
Water Extract ◽  
Rat Tissues ◽  
Synthetase Activity ◽  
Specific Measure ◽  
Glutamine Synthesis ◽  
Methionine Sulphoximine

Two common ways of measuring the potential for glutamine synthesis in a tissue are the rates of formation of γ-glutamylhydroxamate either by synthesis from glutamate (the glutamylhydroxamate synthetase reaction) or by transfer from glutamine (the glutamyltransferase reaction); it has not been established, however, that either reaction is a specific measure of glutamine synthetase. By differential extraction of glutamylhydroxamate synthetase and glutamyltransferase activities from water homogenates of several rat tissues I obtained an extract, rich in glutamylhydroxamate synthetase activity but nearly devoid of glutamyltransferase activity, and a fraction, solubilized by deoxycholate from the pellet, which contained virtually no glutamylhydroxamate synthetase activity but most of the original glutamyltransferase activity. Synthesis of glutamine, quantitatively similar to the γ-glutamylhydroxamate formed by glutamylhydroxamate synthetase, is catalysed in the water extract but not in the particulate fraction. γ-Glutamylhydroxamate formation by glutamylhydroxamate synthetase and glutamyltransferase shows discrepant substrate and metal specificities and can be differentially inhibited by l-methionine sulphoximine, phosphate and adenine nucleotides. The concordance between the formation of glutamine and γ-glutamylhydroxamate by glutamylhydroxamate synthetase but not by glutamyltransferase and the different solubilities of the glutamylhydroxamate synthetase and glutamyltransferase enzyme activities demonstrate that these two activities are not inextricably associated; they therefore cannot be catalysed exclusively by the same protein.

IN VIVO INTERCONVERSION FACTORS BETWEEN OESTRONE AND 17 -OESTRADIOL IN RAT TISSUES ( TT)

1971 ◽  
Vol 66 (3) ◽  
pp. 417-430 ◽  
Author(s):  
R. D. Hertogh ◽  
E. Ekka ◽  
I. Vanderheyden
Keyword(s):  
Rat Tissues

Secondary biosynthesis of aflatoxin B1 in Aspergillus parasiticus

1970 ◽  
Vol 16 (10) ◽  
pp. 959-963 ◽  
Author(s):  
R. W. Detroy ◽  
C. W. Hesseltine
Keyword(s):  
Protein Synthesis ◽  
Aflatoxin B1 ◽  
Aspergillus Parasiticus ◽  
Synthetase Activity ◽  
Macromolecular Synthesis ◽  
High Concentration ◽  
Methyl Group ◽  
Aflatoxin B ◽  
Concentration Levels

The effect of two inhibitors on the formation of aflatoxin B1 synthetase activity in strain NRRL 2999 Aspergillus parasiticus has been studied. Aflatoxin B1 synthesizing activity was measured in vivo by incorporation of the 14C-methionine methyl group into aflatoxin B1. Cycloheximide at a concentration of 150 μg/ml blocks protein synthesis completely. If addition of cycloheximide is made before B1 synthetase appears, no activity accumulates; if added during accumulation, activity is frozen at the level reached at the time of addition. The cycloheximide effect is reversible since morphogenesis, total protein synthesis, and aflatoxin B1 synthetase activity all resume after removal of the inhibitor.DL-p-Fluorophenylalanine partially inhibits aflatoxin B1 synthesis in vivo; however, its effect upon macromolecular synthesis is incomplete even at high concentration levels. Once formed, the aflatoxin synthetase appears to maintain B1 synthesis when further protein synthesis is blocked; i.e., it is not rapidly degraded.

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