Metabolic studies of [75Se]selenocystine and [75Se]selenomethionine in the rat

1. The long-term fate in rats of an oral dose of [75Se]selenocystine was compared with that of an oral dose of [75Se]selenomethionine.2. Urinary and faecal radioactivities were measured during the 1st week and whole-body radioactivity was determined for 10 weeks. Rats were killed at weekly intervals for 4 weeks and at weeks 6 and 10 for analysis of tissue distribution of 75Se.3. Intestinal absorption of [75Se]selenocystine was 81% of the administered dose; that of [75Se]selenomethionine was 86%. Urinary excretion of absorbed [75Se]selenocystine was 13.9% and that of [75Se]selenomethionine was 5.8%, in the 1st week.4. Whole-body retention of 75Se was greater for [75Se]selenomethionine than for [75Se]-selenocystine but after the 1st week it decreased at a similar rate in both groups. Tissue distribution of retained 75Se was also similar in both groups.5. The initial utilization of [75Se]selenocystine was different from that of [75Se]selenomethionine. However, after the 1st week 75Se from both sources appeared to be metabolized similarly, suggesting that dietary Se of both forms is ultimately incorporated into the same metabolic pool.6. When these findings were compared with those of earlier studies with [75Se]selenite and 75Se incorporated in vivo into rabbit kidney (RK-75Se) (Thomson, Stewart & Robinson, 1975) the metabolism of [75Se]selenocystine resembled that of [75Se]selenite and RK-75Se, rather than that of [75Se]selenomethionine.

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Metabolic studies in rats of [75Se]selenomethionine and of 75Se incorporated in vivo into rabbit kidney

British Journal Of Nutrition ◽

10.1079/bjn19750007 ◽

1975 ◽

Vol 33 (1) ◽

pp. 45-54 ◽

Cited By ~ 22

Author(s):

Christine D. Thomson ◽

R. D. H Stewart ◽

Marion F. Robinson

Keyword(s):

Oral Dose ◽

Tissue Distribution ◽

Similar Rate ◽

Whole Body ◽

Rabbit Kidney ◽

Kidney Homogenate ◽

Body Retention ◽

Metabolic Pool

1. [75Se]selenomethionine was administered to four rabbits and after 4 d their kidneys were removed and homogenized. The long-term fate in rats of an oral dose of this kidney homogenate (RK-75Se) was compared with that of an oral dose of [75Se]selenomethionine mixed with unlabelled rabbit kidney homogenate.2. Urinary and faecal radioactivities were measured during the 1st week and whole-body radioactivity was determined for 10 weeks. Rats were killed at weekly intervals for 4 weeks for analysis of tissue distribution of 75Se.3. Intestinal absorption of RK-75Se was 87%; that of [75Se]selenomethionine was 91%. Urinary excretion of absorbed RK-75Se was 13·3% and that of [75Se]selenomethionine was 7·6%, in the 1st week.4. Whole-body retention of 75Se was greater for [75Se]selenomethione than for RK-75Se but after the 1st week decreased at a similar rate in both groups. Tissue distribution of retained 75Se was also similar in both groups.5. The initial utilization of 75Se in rabbit kidney is different from that of [75Se]selenomethionine. However, after the 1st week 75Se from these sources appears to be metabolized similarly, suggesting that Se from both is ultimately incorporated into the same metabolic pool.

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Metabolic studies of [75Se]selenomethionine and [75Se]selenite in the rat

British Journal Of Nutrition ◽

10.1079/bjn19730015 ◽

1973 ◽

Vol 30 (1) ◽

pp. 139-147 ◽

Cited By ~ 66

Author(s):

Christine D. Thomson ◽

R. D. H. Stewart

Keyword(s):

Oral Administration ◽

Urinary Excretion ◽

Tissue Distribution ◽

Intestinal Absorption ◽

Initial Period ◽

Similar Rate ◽

Whole Body ◽

Body Retention ◽

Metabolic Pool

1. Information was sought concerning the long-term fate of orally and intravenously administered [75Se]selenomethionine and [75Se]selenite in rats.2. Urinary and faecal radioactivity was assayed during the 1st week and whole-body radio-activity was determined weekly for 16 weeks. Rats were killed at intervals for analysis of 75Se tissue distribution.3. Intestinal absorption after oral administration was estimated to be 91–93% for selenite and 95–97% for selenomethionine.4. Urinary excretion of absorbed [75Se]selenite was greater than that of [75Se]selenomethionine during the 1st week.5. After the 1st week, whole-body retention diminished exponentially at a similar rate in rats given either selenomethionine or selenite. Except for the erythrocytes, 75Se content of individual tissues also decreased exponentially.6. It appears that, after an initial period, 75Se from either selenomethionine or selenite is metabolized similarly, suggesting that Se from both potential dietary sources is ultimately incorporated into the same metabolic pool.

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Metabolic studies in rats of 75Se incorporated in vivo into fish muscle

British Journal Of Nutrition ◽

10.1079/bjn19770057 ◽

1977 ◽

Vol 38 (1) ◽

pp. 19-29 ◽

Cited By ~ 15

Author(s):

Margaret Richold ◽

Marion F. Robinson ◽

R. D. H. Stewart

Keyword(s):

Oral Dose ◽

Tissue Distribution ◽

Absorbed Dose ◽

Fish Muscle ◽

Whole Body ◽

Rabbit Kidney ◽

List Type ◽

Faecal Excretion

1.[75Se]selenite or [75Selenomethionine was injected into the coelomic cavity of fish. After 2 d or 14 d the muscle portion of the fish was removed and homogenized. The long-term fate in rats of an oral dose of each labelled homogenate was compared with that of an oral dose of [75Se]selenite or [75Se]selenomethionine mixed with unlabelled fish homogenate.2.Urinary and faecal radioactivity were measured during the 1st week and whole-body radioactivity was determined for 10 weeks. Rats were killed at weekly intervals for 4 weeks for analysis of tissue distribution of 75Se.3.Intestinal absorption of 75Se given as labelled fish homogenate was less complete than that of 75Se mixed with unlabelled homogenate, and the absorption of 75Se from the 14d-labelled fish homogenate derived from [75Se]selenite was less complete than that of 75Se from the other labelled homogenates.4.Urinary excretion of absorbed 75Se in the first 7 d was in the range 5-8 % absorbed dose and was slightly greater in the rats given 75Se as selenite or derived from selenite than in those given 75Se as selenomethionine or derived from selenomethionine. Endogenous faecal excretion of absorbed Se was similar in all groups, as also were tissue distribution of retained 75Se and long-term whole-body turnover rate.5.The results of these studies are compared with those of earlier studies of the metabolism in rats of [75Selenomethionine, [75Se]selenite, [75Sejselenocystine and 75Se incorporated in vivo into rabbit kidney. There were differences in the initial utilization of 75Se from these various sources but after the 1st week 75Se from all sources appeared to be metabolized similarly, suggesting that for rats dietary Se of all forms is ultimately incorporated into the same metabolic pool.

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Simultaneous Assessment of Endothelial Function, Nitric Oxide Synthase Activity, Nitric Oxide–Mediated Signaling, and Oxidative Stress in Individuals with and without Hypercholesterolemia

Clinical Chemistry ◽

10.1373/clinchem.2007.093575 ◽

2008 ◽

Vol 54 (2) ◽

pp. 292-300 ◽

Cited By ~ 34

Author(s):

Renke Maas ◽

Edzard Schwedhelm ◽

Lydia Kahl ◽

Huige Li ◽

Ralf Benndorf ◽

...

Keyword(s):

Nitric Oxide ◽

Endothelial Function ◽

Urinary Excretion ◽

Indirect Evidence ◽

No Oxidation ◽

Whole Body ◽

Gas Chromatography Mass Spectrometry ◽

Synthesis Rate ◽

No Production

Abstract Background: Endothelial function is impaired in hypercholesterolemia and atherosclerosis. Based on mostly indirect evidence, this impairment is attributed to reduced synthesis or impaired biological activity of endothelium-derived nitric oxide (NO). It was the aim of this study to directly estimate and compare whole-body NO production in normo- and hypercholesterolemia by applying a nonradioactive stable isotope dilution technique in vivo. Methods: We enrolled 12 normocholesterolemic and 24 hypercholesterolemic volunteers who were all clinically healthy. To assess whole-body NO synthesis, we intravenously administered l-[guanidino-(15N2)]-arginine and determined the urinary excretion of 15N-labeled nitrate, the specific end product of NO oxidation in humans, by use of gas chromatography-mass spectrometry. In addition, we measured flow-mediated vasodilation (FMD) of the brachial artery, expression of endothelial NOS (eNOS) in platelets, plasma concentration of the endogenous NOS inhibitor asymmetric dimethylarginine (ADMA), and urinary excretion of 8-isoprostaglandin F2α (8-iso-PGF2α). Results: After infusion of l-[guanidino-(15N2)]-arginine, cumulative excretion of 15N-labeled-nitrate during 48 h was 40% [95% CI 15%–66%] lower in hypercholesterolemic than normocholesterolemic volunteers [mean 9.2 (SE 0.8) μmol vs 15.4 (2.3) μmol/l, P = 0.003]. FMD was on average 36% [4%–67%] lower in hypercholesterolemic than normocholesterolemic volunteers [6.3 (4.0)% vs 9.4 (4.6)%, P = 0.027]. Normalized expression of NOS protein in platelets was also significantly lower in hypercholesterolemic volunteers, whereas there were no significant differences in plasma ADMA concentration or urinary excretion of 8-iso-PGF2α between the 2 groups. Conclusions: This study provides direct evidence for a decreased whole body NO synthesis rate in healthy people with hypercholesterolemia.

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Whole-body Retention and Tissue Distribution of Cesium-134 in New-born, Young and Adult Rats

Journal of Radiation Research ◽

10.1269/jrr.8.132 ◽

1967 ◽

Vol 8 (3-4) ◽

pp. 132-140 ◽

Cited By ~ 7

Author(s):

Jiro INABA ◽

Naonori MATSUSAKA ◽

Ryushi ICHIKAWA

Keyword(s):

Tissue Distribution ◽

Whole Body ◽

Adult Rats ◽

New Born ◽

Body Retention

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Whole-body Retention, Tissue Distribution and Excretion of Selenium-75 after Oral and Intravenous Administration in Lambs Fed Varying Selenium Intakes

Journal of Nutrition ◽

10.1093/jn/97.1.123 ◽

1969 ◽

Vol 97 (1) ◽

pp. 123-132 ◽

Cited By ~ 25

Author(s):

Perla L. Lopez ◽

R. L. Preston ◽

W. H. Pfander

Keyword(s):

Tissue Distribution ◽

Intravenous Administration ◽

Whole Body ◽

Body Retention ◽

Selenium 75

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The effect of short-term and long-term application of fisetin on experimentally induced airway hyperreactivity

European Pharmaceutical Journal ◽

10.1515/afpuc-2017-0005 ◽

2017 ◽

Vol 64 (1) ◽

pp. 7-9

Author(s):

I. Kazimierová ◽

L. Pappová ◽

M. Šútovská ◽

S. Fraňová

Keyword(s):

Airway Inflammation ◽

Airway Resistance ◽

Chronic Administration ◽

Airway Hyperreactivity ◽

Whole Body ◽

Short Term ◽

Specific Airway Resistance ◽

Term Administration

AbstractBackground:Fisetin, a derivate from the flavonol group may possess a variety of pharmacological effects. The aim of the presented study was to evaluate the bronchodilatory effect of fisetin after the acute or the chronic administration to guinea pigs with allergic airway inflammation.Methods:Experimental animals were sensitized and challenged by ovalbumin. Fisetin was administered in dose 5mg/kg/p.o., either once after the end of 21-days sensitization or daily during the 21-days sensitization. By using the whole-body plethysmograph, we monitored the specific airway resistance, a parameter of airway hyperreactivityin vivo. The changes of the specific airway resistance were evaluated after the short-term inhalation of the bronchoconstriction mediator-histamine (10−6mol.1−1).Results:Our results showed that the short-term as well as the long-term administration of fisetin caused decrease of the specific airway resistance values. The bronchodilatory effect of fisetin was comparable to the long-acting beta2sympathomimetic – salmeterol after the long-term administration. The measurements of the bronchodilatory activity after single administration have revealed more prolonged effect of fisetin comparing to the short-acting beta2sympathomimetic – salbutamol, as this remained even after the 5 hours, when salbutamol was already ineffective.Conclusion:In conclusion, flavonol – fisetin has shown bronchodilatory potential. In the light of this fact, fisetin may represent potential substance that can be effective in both prevention as well as control of airway inflammation symptoms.

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Consequences of prenatal and preweaning growth for yield of beef primal cuts from 30-month-old Piedmontese- and Wagyu-sired cattle

Animal Production Science ◽

10.1071/ea08160 ◽

2009 ◽

Vol 49 (6) ◽

pp. 468 ◽

Cited By ~ 17

Author(s):

P. L. Greenwood ◽

L. M. Cafe ◽

H. Hearnshaw ◽

D. W. Hennessy ◽

S. G. Morris

Keyword(s):

Growth Rate ◽

Environmental Factors ◽

Tissue Distribution ◽

Early Life ◽

Low Birthweight ◽

Carcass Weight ◽

Whole Body ◽

Target Market ◽

Subsequent Growth

Cattle sired by Piedmontese or Wagyu bulls were bred and grown within pasture-based nutritional systems followed by feedlot finishing. Effects of low (mean 28.6 kg, n = 120) and high (38.8 kg, n = 120) birthweight followed by slow (mean 554 g/day, n = 119) or rapid (875 g/day, n = 121) growth to weaning on beef primal cut weights at ~30 months of age were examined. Cattle of low birthweight or grown slowly to weaning had smaller primal cuts at 30 months as a result of reduced liveweight and smaller carcasses compared with their high birthweight or rapidly grown counterparts. Hence they require additional nutritional and economic inputs to reach target market weights. At equivalent carcass weights (380 kg), cattle restricted in growth from birth to weaning yielded slightly more beef and were somewhat leaner than their rapidly grown counterparts, resulting in primal cuts being up to 4% heavier in the slowly grown compared with the rapidly grown cattle. Compositional differences due to birthweight were less apparent at the same carcass weight, although low birthweight cattle had a slightly (~2%) heavier forequarter and slightly lower (~1%) hindquarter retail yield, and less shin-shank meat (~2%) than high birthweight cattle, suggesting only minor effects on carcass tissue distribution. There were few interactions between sire genotype and birthweight or preweaning growth, and interactions between birthweight and preweaning growth were not evident for any variables. However, variability between cohorts in their long-term responses to growth early in life suggests other environmental factors during early-life and/or subsequent growth influenced carcass yield characteristics. Overall, this study shows that effects of birthweight and preweaning growth rate on carcass compositional and yield characteristics were mostly explained by variation in carcass weight and, hence, in whole body growth to 30 months of age.

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In vivo mucosal uptake, mucosal transfer and retention of iron in mice

Laboratory Animals ◽

10.1258/002367797780596329 ◽

1997 ◽

Vol 31 (3) ◽

pp. 264-270 ◽

Cited By ~ 10

Author(s):

M. Santos ◽

K. J. H. Wienk ◽

M. W. Schilham ◽

H. Clevers ◽

M. de Sousa ◽

...

Keyword(s):

Iron Absorption ◽

Iron Status ◽

Test Dose ◽

Whole Body ◽

Whole Body Counter ◽

Significant Difference ◽

Transfer And Retention ◽

Iron Retention

An improved and sensitive method for studying iron absorption in mice with alterations in body iron stores is described. Mice with varying iron status were given a double isotope-labelled test dose containing 59Fe and 51Cr as a non-absorbable indicator, via an oroesophageal needle. Using a whole-body counter it was possible to measure in vivo the initial mucosal iron uptake and long-term iron retention and to calculate mucosal iron transfer. A significant difference was demonstrated between normal and both anaemic and dietary iron-loaded mice with regard to the various steps of iron absorption. When mice were tested twice for iron absorption, the results were highly reproducible. In conjunction with other parameters, the method described is useful in studying the mechanism and the regulation of iron absorption in mice.

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