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1.
A deficiency or an excess of some elements in the diet is reported to modify the concentration of cholesterol in plasma, and, conversely, a reduction of cholesterol in the diet decreases zinc in plasma. We have studied the distribution of elements Na, K, Ca, Mg, Fe, Cu, Zn, S, P, and Mn in the tissues, plasma, heart, aorta, lung, liver, spleen, kidney, thymus, and brain of New Zealand White rabbits (NZW) and of Watanabe Heritable Hyperlipidemic rabbits (WHHL). The WHHL rabbits had a massive hypercholesterolemia (7.45 +/- 1.2 g/L) induced by a lack of liver low density lipoprotein receptors. The concentrations of elements in the tissues of the control NZW rabbits were very similar to those found in the normal rat. In WHHL, compared to NZW, besides the very important increase of total phosphorus in plasma explained by the augmentation of phospholipids, there was an increase of plasma copper (+44%) and zinc (+36%). The other noticeable changes were an increase of iron in heart (+19%), sulfur, and zinc in liver (+15% and +18%). The other changes observed in WHHL rabbits were, besides the increase of ceruloplasmin, the increase of vit E (+468%) and MDA (+62%). In conclusion, despite a massive increase of lipids in plasma, there was no major disturbance of element distribution in WHHL rabbits.  相似文献   

2.
Ethylene diamine tetraacetic acid (EDTA), nitrilotriacetic acid (NTA), and tripolyphosphate (TPP) sodium salts were given orally to rats at the dose of 1 mmol/kg/d for 35 d. The concentrations of Na, K, Ca, Mg, P, S, Fe, Sr, Cu, and Zn were determined in blood, plasma, brain, heart, muscle, liver, kidney, duodenum, and bone of control rats and of the rats receiving EDTA, NTA, and TPP. The main effect induced by EDTA, NTA, and TPP was a decrease of the concentrations of several elements Ca, Mg, Fe, P in the duodenum. Otherwise, EDTA induced an increase of Zn in the kidney (+ 20%), NTA, an increase of Fe in liver (+ 29%), and particularly an increase of Zn in bone (+ 44%). TPP induced a slight decrease of Zn and Cu in liver. In conclusion, EDTA, NTA, and TPP taken orally at the dose of 1 mmol/kg/d for 35 d induced moderate changes of the concentrations of some elements in rat tissues, but without signs of toxicity.  相似文献   

3.
It is recognized that the development of hypertension in Dahl salt-sensitive (DS) rats as compared to Dahl salt-resistant (DR) rats is dependent on the addition of a high percentage of sodium chloride, often 8% to the diet. In this work, blood systolic pressure and the concentrations of many elements in different tissues of DS and DR rats were measured. However, to distinguish the modifications linked to the strain from the modifications owing to excess of sodium intake, no additional Na was included in the diet in all our experiments. Without any addition of sodium chloride to the diet, a statistically significant increase of the systolic blood pressure of DS rats (152±10 mmHg) in comparison to DR rats (131 +/? 3 mmHg) was observed. The analysis of the concentrations of many elements in different tissues showed no major modifications of sodium concentrations in DS rats as compared to DR rats, but a decrease of calcium in plasma (?9%), brain (?20%), and heart (?7%) and of magnesium in plasma (?13%), kidney (?11%), and bone (?7%). In conclusion, an increased intake of Na is not necessary to obtain a higher systolic blood pressure in DS rats compared to DR rats. Since we did not find noticeable modifications of Na concentration in tissues but modifications of Ca and Mg, we suggest that an alteration of the homeostasis of these two elements may be involved in the development of the hypertension in DS rats.  相似文献   

4.
研究不同ALA含量油脂对高脂模型大鼠组织脂肪酸代谢的影响.60只雄性Wistar大鼠分为正常组、高脂组、花生油组、13%、27%和55% ALA含量油脂组,除正常组和高脂组外,其余各组在饲喂高脂饲料的同时采用灌胃方式连续给予2 mL/kg.bw剂量的受试油.试验6周后分别测定大鼠各组织脂肪酸组成.结果表明,高脂饮食能够降低大鼠各组织n-3脂肪酸含量,但摄入不同ALA油脂可显著增加组织n-3脂肪酸含量,并具有一定的剂量效应关系;但ALA及其代谢产物EPA、DPA和DHA的累积具有组织特异性,其中肾和心组织中ALA累积高于血浆、脑及肝组织,肝和脑组织中EPA和DPA含量增加较显著,而肾和心组织中EPA含量不变,各组织DHA含量增加不显著.不同ALA油脂组C18:3(n-6)和C20:3 (n-6)差异不显著,但与花生油组相比,其血浆、脑和肾组织C20:4含量显著降低.因此,富含ALA含量的油脂能够增加组织中ALA及其代谢产物在组织中的含量,提高其在脑组织中的分布比例,这可能是ALA具有心血管保护作用和促进脑生长发育的作用机制之一.  相似文献   

5.
The purpose of this study was to investigate the possible antioxidant effect of an aqueous extract of Ajuga iva (Ai) in streptozotocin (STZ)-induced diabetic rats. Twelve diabetic rats were divided into two groups fed a casein diet supplemented or not with Ai (0.5%), for 4 weeks. In vitro, the Ai extract possessed a very high antioxidant effect (1 mg/ml was similar to those of trolox 300 mmol/l). The results indicated that plasma thiobarbituric acid reactive substances (TBARS) values were reduced by 41% in Ai-treated compared with untreated diabetic rats. TBARS concentrations were lower 1.5-fold in liver, 1.8-fold in heart, 1.9-fold in muscle and 2.1-fold in brain in Ai-treated than untreated group. In erythrocytes, Ai treatment increased significantly the activities of glutathione peroxidase (GSH-Px) (+25%) and glutathione reductase (GSSH-Red) (+22%). Superoxide dismutase activity was increased in muscle (+22%), while GSH-Px activity was significantly higher in liver (+28%), heart (+40%) and kidney (+45%) in Ai-treated compared with untreated group. Liver and muscle GSSH-Red activity was, respectively, 1.6- and 1.5-fold higher in Ai-treated than untreated diabetic group. Catalase activity was significantly increased in heart (+36%) and brain (+32%) in Ai-treated than untreated group. Ai treatment decreased plasma nitric oxide (?33%), carbonyls (?44%) and carotenoids (?68%) concentrations. In conclusion, this study indicates that Ajuga iva aqueous extract improves the antioxidant status by reducing lipid peroxidation and enhancing the antioxidant enzymes activities in plasma, erythrocytes and tissues of diabetic rats.  相似文献   

6.
The hypothesis tested was whether marginal iodine deficiency for a period of 6 wk affects iodothyronine deiodinase activities in liver and brain of rats. Male rats were fed purified diets either deficient or sufficient in iodine; the diets were fed on a restricted basis (60% ofad libitum intake). Body weight gain of the two groups was comparable. Iodine deficiency was evidenced by increased thyroid weight (26%), reduced urinary iodine excretion (80%), and reduced plasma T4 concentrations (22%). Activities of liver type I and brain type III deiodinase were unchanged, but the activity of type II deiodinase in brain was increased (28%) in the iodine-deficient rats. Food restrictionper se significantly lowered T3 (30%) and T4 (22%) concentrations in plasma and decreased type III deiodinase activity in brain (30%). These results indicate that in marginal iodine deficiency the activities of hepatic type I deiodinase and brain type III deiodinase are unchanged, whereas that of brain type II deiodinase is increased.  相似文献   

7.
Creatine is a nutritional supplement with major application as ergogenic and neuroprotective substrate. Varying supplementation protocols differing in dosage and duration have been applied but systematic studies of total creatine (creatine and phosphocreatine) content in the various organs of interest are lacking. We investigated changes of total creatine concentrations in brain, muscle, heart, kidney, liver, lung and venous/portal plasma of guinea pigs, mice and rats in response to 2-8 weeks oral creatine-monohydrate supplementation (1.3-2 g/kg/d; 1.4-2.8% of dietary intake). Analysis of creatine and phosphocreatine content was performed by high performance liquid chromatography. Total creatine was determined as the sum of creatine and phosphocreatine. Presupplementation total creatine concentrations were high in brain, skeletal and heart muscle (10-22 micromol/g wet weight), and low in liver, kidney and lung (5-8 micromol/g wet weight). During creatine supplementation, the relative increase of total creatine was low (15-55% of presupplementation values) in organs with high presupplementation concentrations, and high (260-500% of presupplementation values) in organs with low presupplementation concentrations. The increase of total creatine concentrations was most pronounced after 4 weeks of supplementation. In muscle, brain, kidney and lungs, an additional increase (p<0.01) was observed between 2-4 and 2-8 weeks of supplementation. Absolute concentrations of phosphocreatine increased, but there was no increase of the relative (percentual) proportion of phosphocreatine (14-45%) during supplementation. Statistical comparison of total creatine concentrations across the species revealed no systematically differences in organ distribution and in time points of supplementation. Results suggest that in organs with low presupplementation creatine levels (liver, kidney), a major determinant of creatine uptake is an extra-intracellular concentration gradient. In organs with high presupplementation total creatine levels like brain, skeletal and heart muscle, the maximum capacity of creatine accumulation is low compared to other organs. A supplementation period of 2 to 4 weeks is necessary for significant augmentation of the creatine pool in these organs.  相似文献   

8.
A sensitive and rapid in vitro assay of 25-hydroxyvitamin D3 [25-(OH)D3]-1 alpha- and 24-hydroxylase activities was developed using rat kidney homogenates. A potent inhibitor of the enzymes in rat plasma was removed by thoroughly perfusing rats with saline. Kidney homogenates prepared from vitamin D-deficient rats preferentially produced tritiated 1 alpha,25-dihydroxyvitamin D3 [1 alpha,25(OH)2D3] from 25(OH) [3H]D3. Addition of 10 microliter or more of rat plasma to 3 ml of 10% kidney homogenates suppressed 1 alpha-hydroxylase activity dose-dependently. Thyroparathyroidectomy (TPTX) of vitamin D-deficient rats greatly abolished 1 alpha-hydroxylase activity. Administration of parathyroid hormone to the TPTX rats increased 1 alpha-hydroxylase activity and that of 1 alpha,25(OH)2D3 enhanced 24-hydroxylase markedly. Since this assay is technically simple, rapid and sensitive, it will be useful in studying the regulatory mechanism in the renal metabolism of 25(OH)D3 in mammals.  相似文献   

9.
We studied in the rat the effects of the drug etretinate (Tigason), given at three doses 3, 10, and 30 mg/kg body wt for 1 mo, on the concentrations of Na, K, Ca, Mg, Fe, S, P, Cu, and Zn in the plasma, brain, thymus, heart, liver, lung, kidney, testicle, muscle, and bone. The elements were simultaneously determined in tissues after nitric acid dissolution by inductively coupled plasma emission spectrometry using a JY 48 instrument. At the dose of 3 mg/kg, etretinate did not induce any statistically significant modifications of the element distribution. At the dose of 10 mg/kg, the main observed modifications were in plasma an increase of copper (+38%) and a decrease of zinc (-25%). At the highest dose of 30 mg/kg, some variations of the concentrations of elements in tissues were observed. But, on no account did retinoids induce an alteration of the mineral composition of bone, despite obvious macroscopic bone alterations.  相似文献   

10.
Tissue-specific alterations in 11beta-hydroxysteroid dehydrogenase (HSD) type 1 activity, which amplifies glucocorticoid action, are thought to contribute to some of the metabolic complications of obesity. The present study tested whether hypertriglyceridemia is one such complication by investigating the effects of an 11beta-HSD1 inhibitor (compound A, 3 mgxkg(-1)xday(-1), 21 days) on triglyceride (TG) metabolism in a rat model of diet-induced obesity. The dose of compound A used did not affect food intake or final body weight. Compound A improved fasting triglyceridemia (-42%) through a robust reduction (-41%) in hepatic TG secretion rate, without change in plasma TG clearance rate. Uptake of TG-derived fatty acids was, however, increased in oxidative tissues, including red gastrocnemius (+47%), heart (+39%), and brown adipose tissue (BAT, +46%) at the expense of the liver, with a concomitant increase in plasma membrane fatty acid-binding protein. Lipid oxidation products were increased in red gastrocnemius (+35%) and heart (+33%), as were levels of uncoupling protein 1 mRNA in BAT (+48%), and carnitine palmitoyltransferase 1 activity tended to be increased in some oxidative tissues. These findings demonstrate that pharmacological inhibition of 11beta-HSD1 at a dose that does not affect food intake improves triglyceridemia by reducing hepatic very low density lipoprotein-TG secretion, with a shift in the pattern of TG-derived fatty acid uptake toward oxidative tissues, in which lipid accumulation is prevented by increased lipid oxidation.  相似文献   

11.
Plasma atrial natriuretic factor (ANF) paradoxically decreases after 5 weeks (but not after 3 weeks) of 8% NaCl intake in normotensive rats. As this phenomenon remains unaccounted for by changes in ANF production, we studied the disappearance of [125I]ANF(99-126) from the circulation as an alternative explanation of plasma ANF decline. Following 5 weeks (but not 3 weeks) of an 8% NaCl diet, plasma concentrations of [125I]ANF were significantly decreased and metabolic clearance rate and volume of distribution were increased compared to control rats fed a 0.8% NaCl diet. By studying [125I]ANF tissue uptake we noted significantly greater peptide uptake after 5 weeks (but not after 3 weeks) of high salt consumption in several tissues. We hypothesize that prolonged (at least 5 weeks) 8% NaCl ingestion increases the density and/or affinity of ANF binding sites. These changes may be responsible for the previously observed decline in plasma ANF concentrations after a prolonged high salt intake.  相似文献   

12.
Mineral (phosphorus, sulfur, potassium, calcium, magnesium, iron, zinc, copper, and manganese) concentrations were measured in plasma, and several tissues from female Wistar rats (young: 3-wk-old; mature: 6-mo-old) were fed on a dietary regimen designed to study the combined or singular effects of age and dietary protein on mineral status. Three diets, respectively, contained 5, 15, and 20% of bovine milk casein. Nephrocalcinosis chemically diagnosed by increased calcium and phosphorus in kidney was prevented in rats fed a 5% protein diet. Renal calcium and phosphorus were more accumulated in young rats than mature rats. A 5% protein diet decreased hemoglobin and blood iron. The hepatic and splenic iron was increased by a 5% protein diet in mature rats but was not altered in young rats. Mature rats had higher iron in brain, lung, heart, liver, spleen, kidney, muscle, and tibia than young rats. A 5% protein diet decreased zinc in plasma and liver. Zinc in tibia was increased with dietary protein level in young rats but was not changed in mature rats. A 5% protein diet decreased copper concentration in plasma of young rats but not in mature rats. Mature rats had higher copper in plasma, blood, brain, lung, heart, liver, spleen, and kidney than young rats. With age, manganese concentration was increased in brain but decreased in lung, heart, liver, kidney, and muscle. These results suggest that the response to dietary protein regarding mineral status varies with age.  相似文献   

13.
Previous work has shown that a low dietary intake of zinc for a short duration significantly lowers the lymphatic absorption of α-tocopherol (αTP) in adult male rats. The present study investigated whether the nutritional status of zinc is critical in maintaining the tissue levels of the vitamin. One group of rats was fed an AIN-93G diet containing 3 mg zinc/kg (low zinc, LZ) and the other was fed the same diet but containing 30 mg zinc/kg (adequate zinc, AZ). Food intakes between groups were matched by feeding two meals per day. At 6 wk, the body weights (356±8 g) of LZ rats reached 98% those (362±10 g) of AZ rats. Feeding of the LZ diet for 6 wk significantly lowered the concentrations of both αTP and zinc in the liver, kidney, heart, testis, and brain. No consistent relationships between αTP and zinc concentrations were observed in other tissues such as spleen, lung, gastrocnemius muscle, and retroperitoneal fat tissues. The concentrations of αTP in the liver, testis, brain, spleen, heart, and kidney were significantly correlated with the tissue concentrations of zinc. The LZ diet slightly but significantly increased the total lipid contents (mg/g) of liver, kidney, heart, and spleen. However, the tissue levels of phospholipid (μmol/100 mg lipid) in the heart, lung, testis, and spleen were decreased significantly in LZ rats. These findings indicate that low zinc intake results in a pronounced decrease in the animal’s αTP status under the conditions of matched food intakes, body weights, and feeding patterns. The lower tissue levels of αTP may explain in part the compromised antioxidant defense system and increased susceptibility to oxidative damage observed in zinc deficiency.  相似文献   

14.
The hypothesis was tested that there are interactions of marginal copper and vitamin A deficiency regarding iron and zinc status. Copper restriction (1 vs 5 mg Cu/kg diet) significantly lowered copper concentrations in plasma and tissues of rats and reduced blood hemoglobin, hematocrit, and iron concentrations in tibia and femur, but raised iron concentrations in liver. Vitamin A restriction (0 vs 4000 IU vitamin A/kg diet) reduced plasma retinol concentrations and induced a fall of blood hemoglobin and hematocrit. Neither copper nor vitamin A restriction for up to 42 d affected feed intake and body wt gain. There were no interrelated effects of vitamin A and copper deficiency on iron status. Copper deficiency slightly depressed liver, spleen, and kidney zinc concentrations. Vitamin A deficiency lowered zinc concentrations in heart, but only when the diets were deficient in copper.  相似文献   

15.
125I-somatomedin A (SMA) was injected iv into rats. Distribution studies in rats showed concentrations of radioactivity to be high in kidney and plasma, low in brain, and intermediate in other tissues. The concentration of total and trichloracetic acid (TCA) precipitable radioactivity in rat blood and tissues fell at rapid rate. Ninety per cent of the radioactivity was in the urine in 24 hr, and only 15% of urine radioactivity was TCA precipitable. The half-life of the radioactivity in TCA-precipitable fraction from blood and that from tissues were nearly identical (about 6 hr). In both liver and kidney, TCA-precipitable radioactivity was detected in membrane and/or organellar fraction and cytosol fraction. Sephadex G-200 chromatography at neutral PHY AT NEUTRAL PH of plasma after injection of 125I-SMA revealed 3 peaks of radioactivity in higher molecular weight region than purified SMA.  相似文献   

16.
The dose-response relationship in brain, plasma, and adrenal monoamine changes after acute oral ethanol administration (1, 2, 4 g/kg body wt) was studied in virgin rats to determine whether the response to the highest dose differed in 21-day pregnant animals, and to assess the potential consequences of ethanol on the neurotransmitter systems of their fetuses. Blood ethanol and acetaldehyde concentrations in blood increased progressively with the ethanol dose in virgin rats, and values in pregnant animals were very similar. Ethanol concentration in fetal blood and amniotic fluid did not differ from that in mother's blood whereas fetal acetaldehyde concentrations were negligible. In a dose-related manner, ethanol decreased brain DA, DOPAC and 5HT concentrations did not affect those of NA and 5HIAA, or adrenal A and NA concentrations, whereas it enhanced plasma NA levels. Basal levels of monoamines and their changes after ethanol intake did not differ in pregnant and virgin rats. Monoamine and metabolite concentrations were much lower in fetal than in maternal brains whereas plasma and adrenal catecholamine concentrations were very similar and maternal ethanol intake did not modify these fetal parameters in the fetus. Results are in agreement with the known similar metabolic response to ethanol in fed pregnant and virgin rats. The lack of fetal monoamine response to maternal ethanol intake may be a consequence of the incapacity of fetal liver to form acetaldehyde and the ability of the placenta to oxidize maternal acetaldehyde which protects the fetus from maternal alcohol intake at late gestation.  相似文献   

17.
Selenium deficiency for periods of 5 or 6 weeks in rats produced an inhibition of tri-iodothyronine (T3) production from added thyroxine (T4) in brain, liver and kidney homogenate. This inhibition was reflected in plasma T4 and T3 concentrations, which were respectively increased and decreased in selenium-deficient animals. Although plasma T4 levels increased in selenium-deficient animals, this did not produce the normal feedback inhibition on thyrotropin release from the pituitary. Selenium deficiency was confirmed in the animals by decreased selenium-dependent glutathione peroxidase (Se-GSH-Px) activity in all of these tissues. Administration of selenium, as a single intraperitoneal injection of 200 micrograms of selenium (as Na2SeO3)/kg body weight completely reversed the effects of selenium deficiency on thyroid-hormone metabolism and partly restored the activity of Se-GSH-Px. Selenium administration at 10 micrograms/kg body weight had no significant effect on thyroid-hormone metabolism or on Se-GSH-Px activity in any of the tissues studied. The characteristic changes in plasma thyroid-hormone levels that occurred in selenium deficiency appeared not to be due to non-specific stress factors, since food restriction to 75% of normal intake or vitamin E deficiency produced no significant changes in plasma T4 or T3 concentration. These data are consistent with the view that the Type I and Type II iodothyronine deiodinase enzymes are seleno-enzymes or require selenium-containing cofactors for activity.  相似文献   

18.
Since chromium(III) was demonstrated to have antioxidative action, we have decided to study the effect of this element on V-induced LPO in liver and kidney of rats. Outbred 2-month-old, albino male Wistar rats received daily, for a period of 12 weeks: group I (control), deionized water to drink; group II, sodium metavanadate (SMV) solution at a concentration of 0.100mgV/mL; group III, chromium chloride (CC) solution at a concentration of 0.004mgCr/mL and group IV, SMV-CC solution at a concentration of 0.100mgV and 0.004mgCr/mL. The particular experimental groups took up with drinking water about 8.6mgV/kg b.w./24h (group II), 0.4mgCr/kg b.w./24h (group III), 9mgV and 0.36mgCr/kg b.w./24h (group IV). The V- or Cr-treated groups had higher concentrations of these two elements in liver and kidney compared to the controls. The administration of vanadium alone caused a significant decrease in fluid intake and in body weight gain compared to the controls. In liver supernatants obtained from all tested rats a statistically significant increase in MDA concentration was demonstrated in spontaneous LPO in comparison with the control rats. Moreover, in rats intoxicated with vanadium alone a statistically significant increase in liver MDA level was observed in the presence of 100microM NaVO(3). Instead, in supernatants of liver received from rats treated with chromium alone, a statistically significant increase in MDA concentration in comparison with the controls was found in the presence of 400microM NaVO(3). In kidney supernatants obtained from rats treated with chromium alone, a statistically significant increase in lipid peroxidation was shown in the presence of 30microM FeSO(4) and 400microM NaVO(3). These results show that the tested doses of vanadium(V) and chromium(III) ingested by rats with their drinking water caused significant alterations in internal organs, especially in liver. Under the conditions of our experiment, Cr(III) did not demonstrate antioxidant action, it rather had an oxidant effect.  相似文献   

19.
CD1 mice injected peripherally with either ANG I or ANG II failed to drink substantial amounts of water or NaCl, yet showed strong Fos immunoreactivity (ir) in subfornical organ (SFO). Mice injected with furosemide showed modest stimulation of NaCl intake either 3 or 24 h later, were hypovolemic, and showed elevated plasma renin activity (PRA). The pattern of Fos-ir in the brain after furosemide was similar to that seen after peripheral injection of ANG II. Mice became hypovolemic after subcutaneous injection of polyethylene glycol (PEG), showed large increases in PRA, aldosterone, and water intake, but did not show sodium appetite. PEG-treated mice had strong activation of SFO as well as other brain regions previously shown to be related to ANG-associated drinking in rats. ANG II appears to have a modified role in the behavioral response to fluid loss in mice compared with rats.  相似文献   

20.
Male Sprague-Dawley rats were used to determine the effects of suptoxic and toxic concentrations of selenite in the drinking water on tissue distribution of zinc (Zn), iron (Fe), and copper (Cu). Se (as sodium selenite) was provided in drinking water at concentrations of 0, 2, 4, and 8 ppm. At 19 d, half of the rats in 4 and 8 ppm Sesupplemented groups were kept on drinking water alone for additional 13 d. All rats were sacrificed at the end of 32 d of experiment. Heart, liver, and kidney were analyzed for the concentrations of Fe, Zn, and Cu by atomic absorption spectrophotometry and of Se by a fluorometric method. Results indicated that rats receiving 4 and 8 ppm Se in drinking water showed a marked reduction in food intake and a reduced growth rate. These adverse effects were quickly reversed when high Se intake was discontinued. Se toxicity caused minimal change in zinc status, reduced tissue iron concentrations and caused a marked increase in copper contents in heart, liver, and kidney. The latter findings were only partly reversed after removal of Se in drinking water. The accumulation of Cu in the tissues of Se-toxic rats provides the evidence of some interaction between Se and Cu.  相似文献   

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