scholarly journals Interrelationship of glutathione–cystine transhydrogenase and glutathione reductase in developing rat intestine

1973 ◽  
Vol 132 (3) ◽  
pp. 623-631 ◽  
Author(s):  
Beatrice States ◽  
Stanton Segal

1. Glutathione reductase and glutathione–cystine transhydrogenase activity in supernatant fractions of whole homogenates and homogenates of mucosal and muscular layers were determined in developing rat intestine after determination of the optimum conditions for assay of the two enzymes. In jejunum from adult rat, the Km values for GSSG reductase and GSH–cystine transhydrogenase activities were 0.25mm-GSSG and 0.23mm-cystine respectively. 2. The two activities could be differentiated by stability studies since GSSG reductase was stable at 60°C for 10min and could be stored at 4°C for 24h without loss of activity. GSH–cystine transhydrogenase, on the other hand, was denatured at 60°C and completely inactive after 24h storage at 4°C. 3. Based on calculations of total activities, both enzymes increased from the eighteenth day until the animals were young adults. 4. Total GSSG reductase activity increased at a greater rate with age than total GSH–cystine transhydrogenase activity as evidenced by activity ratios for GSH–cystine transhydrogenase/GSSG reductase of 0.44 and 0.12 in ileum from suckling and adult rats respectively, and 0.31 and 0.24 in jejunum from suckling and adult rats respectively. 5. In mucosa from adult rats GSSG reductase was more active in the ileum than in the jejunum, whereas GSH–cystine transhydrogenase activity was higher in the jejunum. 6. GSH–cystine transhydrogenase was active only in the muscle cells of the ileum of 7-day-old rats but became localized primarily in the mucosal layer in the adult rat. However, GSSG reductase activity was distributed evenly between the two layers throughout the intestine.

1980 ◽  
Vol 186 (2) ◽  
pp. 399-403 ◽  
Author(s):  
P G Holtzapple ◽  
C M Starr ◽  
T Morck

1. Phosphatidylcholine synthesis in the foetal, newborn and adult small intestine of rats was studied by determination of cytidine diphosphocholine-1,2-diacylglycerocholine phosphotransferase (cholinephosphotransferase) and acyl-CoA-1-acyl-sn-glycerol-3-phosphocholine acyltransferase (lysophosphatidylcholine acyltransferase) activities and the incorporation of [1-14C]oleic acid into phosphatidylcholine. 2. Cholinephosphotransferase activity was low in foetal jejunum and ileum, increased 3-4 fold in the ileum by 6 days of age and by 12 days in the jejunum. Jejunal activity remained constant throughout weaning; ileal activity gradually decreased to values 25% of that of the jejunum. 3. Lysophosphatidylcholine acyltransferase activity was high in foetal jejunum and ileum, decreased 70% immediately after birth in the jejunum and increased to adult values by 12 days of age. Ileal activity decreased by 20% after birth, but decreased more rapidly at weaning to 30% of the activity in jejunum. 4. Initial rates and steady-state incorporation of [1-14C]oleic acid into phosphatidylcholine by jejunal rings of 10 day-old rats exceeded that observed in jejunal rings from adult rats by 2-4-fold. 5. In the postnatal jejunum, neither cholinephosphotransferase and lysophosphatidylcholine acyltransferase activities nor oleic acid incorporation were stimulated by cortisone administration in vivo.


1998 ◽  
Vol 275 (4) ◽  
pp. C1143-C1150 ◽  
Author(s):  
James F. Collins ◽  
Pawel R. Kiela ◽  
Hua Xu ◽  
Jiamin Zeng ◽  
Fayez K. Ghishan

We have previously described changes in intestinal brush-border membrane vesicle (BBMV) Na+/H+exchange activity and characterized Na+/H+exchanger (NHE3) expression during rat ontogeny. The current studies were designed to investigate developmental changes in NHE2 expression in rat intestine. In previous studies, pH-dependent uptake of Na+ in jejunal BBMV utilizing HOE-694 inhibition demonstrated that NHE2 functional protein levels were lowest in 2-wk-old rats, higher in 3-wk-old and adult rats, and highest in 6-wk-old rats [Collins et al. Am. J. Physiol. 273 ( Cell Physiol. 42): C1937–C1946, 1997]. In the current investigation, Northern blot analyses showed that NHE2 mRNA levels in the jejunum were similar in 6-wk-old, adult, and 3-wk-old rats and three- to fivefold lower in 2-wk-old rats. In situ hybridization of 2- and 6-wk-old rat intestine with NHE2-specific probes confirmed Northern blot observations. Polyclonal antibodies were developed against an NHE2-specific peptide from amino acids 652–661. Western blots with NHE2 antiserum showed that the intensity of a specific 90-kDa band was lowest in 2-wk-old animals and four- to sixfold higher in 3- and 6-wk-old and adult animals. Immunohistochemical analysis showed specific staining of NHE2 antiserum to only the apical intestinal membrane. Furthermore, nuclear run-on analyses showed a 1.7-fold higher NHE2 transcription rate in 6-wk-old rats than in 2-wk-old rats. Overall, the current data suggest that increases in NHE2 expression upon weaning are mediated by increased gene transcription.


1976 ◽  
Vol 230 (3) ◽  
pp. 845-848 ◽  
Author(s):  
C Peschle ◽  
G Marone ◽  
A Genovese ◽  
C Magli ◽  
M Condorelli

Erythropoietin (Ep) levels were evaluated in serum of neonate, weanling, or adult rats subjected to 1) sham operation, nephrectomy, and/or subtotal hepatectomy and 2) a standard bout of hypoxia (0.45 atm air/6 h, starting 1 h after the operation). Ep activity was quantitated by means of strictly controlled assays in exhypoxic polycythemic mice. The sum of Ep titers in the serum of nephrectomized or hepatectomized rats was compared to Ep levels in sham-operated animals of corresponding age levels, with the exception of 1-wk-old rats: it is relevance that no significant difference is apparent between these Ep production curves. Thus, evidence is presented indicating for the first time that Ep derives from two functionally distinct and additive sources, i.e., the kidney and the liver. Liver Ep, although prevalent in neonatal animals, is obscured in the weanling adult rat by both gradual initiation of massive renal Ep production and progressive decrease of hepatic Ep activity.


2000 ◽  
Vol 78 (3) ◽  
pp. 237-243 ◽  
Author(s):  
Hao Shen ◽  
Krishna G Peri ◽  
Xing-Fei Deng ◽  
Sylvain Chemtob ◽  
Daya R Varma

Distribution of α1-adrenoceptor (α1AR) subtype (α1A, α1B, α1D) proteins in brain, heart, kidney, and liver of 1-week-old rats and in brain, heart, aorta, kidney, liver, vas deferens, prostate, and adrenal glands of adult rats was investigated by Western analysis, using receptor subtype specific polyclonal antibodies. High levels of immunoreactive α1AAR and α1DAR in brain and heart and of α1BAR in liver and heart of neonatal rats were detected. In adult rat tissues, the abundance of α1AAR protein was most marked in the brain, intermediate in heart, aorta, liver, vas deferens, and adrenals, and minimal in the kidney and prostate; relative to other tissues, the expression of α1BAR was higher in brain and heart and that of α1DAR in brain. All the three receptor subtypes increased with age in the brain cortex, whereas the abundance of α1BAR increased in the heart but decreased in the liver; α1AAR and α1DAR in liver, kidney, and heart were not affected by age. It is concluded that α1AR subtypes are widely expressed in different neonatal and adult rat tissues.Key words: α1A-adrenoceptors, α1B-adrenoceptors, α1D-adrenoceptors, α1-adrenoceptor proteins.


1955 ◽  
Vol 33 (3) ◽  
pp. 404-407 ◽  
Author(s):  
H. Bruce Collier ◽  
Sheila C. McRae

Glutathione reductase activity of hemolyzates of human erythrocytes was measured by an amperometric titration of the reduced glutathione that is formed from oxidized glutathione. The electron donor in the system was reduced triphosphopyridine nucleotide, produced by the glucose-6-phosphate dehydrogenase of the cells. Removal of the red-cell stromata from hemolyzates slightly increased the reductase activity. Addition of Na+, K+, or Ca++ had no effect on the enzyme. No marked inhibition was observed in the presence of phenothiazine, phenothiazone, phenylhydrazine, or p-chloromercuribenzoate.


1976 ◽  
Vol 154 (2) ◽  
pp. 559-560 ◽  
Author(s):  
M M. Sudjic ◽  
R Booth

Rat brain contains 3-hydroxy-3-methylglutaryl-CoA reductase activity, but this enzyme is far more active in 7-day-old brain than in adult brain. This difference may partly explain why cholesterol biosynthesis is more rapid in growing than in adult rat brain.


1968 ◽  
Vol 16 (3) ◽  
pp. 185-190 ◽  
Author(s):  
NORBERTO A. SCHOR ◽  
DAVID GLICK

A fluorometric method for determination of glutathione reductase activity in microgram samples of tissue, i.e., microtome sections, based on measurement of the decrease of reduced nicotinamide adenine dinucleotide phosphate due to its oxidation on reaction with oxidized glutathione, was developed and applied to the quantitative histologic distribution of the enzyme in the adrenal gland of the rat. Single subcutaneous injections of adrenocorticotropin in saline solution (25 mg/kg) produced little change of enzyme activity in any of the histologic zones, although there was some tendency for the peak activity to shift from fasciculata to the fascicular-reticular border region. The possible interrelationship of glutathione reductase with ascorbic acid and reduced nicotinamide adenine dinucleotide phosphate in adrenal function was considered.


1955 ◽  
Vol 33 (1) ◽  
pp. 404-407 ◽  
Author(s):  
H. Bruce Collier ◽  
Sheila C. McRae

Glutathione reductase activity of hemolyzates of human erythrocytes was measured by an amperometric titration of the reduced glutathione that is formed from oxidized glutathione. The electron donor in the system was reduced triphosphopyridine nucleotide, produced by the glucose-6-phosphate dehydrogenase of the cells. Removal of the red-cell stromata from hemolyzates slightly increased the reductase activity. Addition of Na+, K+, or Ca++ had no effect on the enzyme. No marked inhibition was observed in the presence of phenothiazine, phenothiazone, phenylhydrazine, or p-chloromercuribenzoate.


1985 ◽  
Vol 249 (4) ◽  
pp. G510-G518
Author(s):  
K. K. Tsuboi ◽  
L. K. Kwong ◽  
K. Yamada ◽  
P. Sunshine ◽  
O. Koldovsky

Adult rats that were maintained on a low-carbohydrate intake showed rapid increase in the activities of sucrase, maltase, and lactase along the length of the small intestine when they were fed a high-starch diet. In the present study, we have identified these activity increases, and showed that they reflect proportional accumulations in enzyme-protein of sucrase-isomaltase (EC 3.2.1.10, 3.2.1.48), maltase-glucoamylase (EC 3.2.1.20), and neutral lactase (EC 3.2.1.23). It was determined that each of these enzymes exists in adult rat intestine in single immunoreactive form and accounts as a group for all sucrase, cellobiase, and most maltase and lactase activities. Dietary change from low to high carbohydrate (starch) resulted in an increase in [3H]leucine accumulation in each of the enzymes, without a change in the amount of label accumulation in total intestinal proteins. The increase in label accumulation in the brush-border carbohydrase pools was matched generally by proportional elevation in the pool concentrations of sucrase-isomaltase and lactase but not maltase. These studies suggest that the elevation of intestinal carbohydrase concentrations induced by high-carbohydrate feeding may involve selective stimulation of their synthesis.


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