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1.
Trace elements such as Zinc (Zn), copper (Cu), iron (Fe), and selenium (Se) are essential for male fertility. The fertilizing capacity of most animals reduced with advancing age. The objective of the present work was to determine the serum and testicular levels of Zn, Cu, and Se in young (10 months old) and old (30 months old) rabbits. Blood and testicular samples were obtained from rabbits after their slaughter. All samples were digested by concentrated acids and analyzed for trace elements by flame emission atomic absorption spectrophotometer. The results showed that serum Zn and Cu were lower in old rabbits than young (P < 0.01). Serum Se was higher in old than young rabbits (P < 0.05). Testicular Cu and Se were significantly lower in old than young rabbits (P < 0.01). However, Zn level was higher in old compared to young rabbits (P < 0.01). The serum Zn and Se were higher than the testicular levels (P < 0.01). The testicular Cu in both ages was higher than the serum level (P < 0.01), which suggest a very important role for Cu in the process of spermatogenesis in rabbits.  相似文献   

2.
The concentration of the toxic elements Ag, As, Cd, Co, Mn, Mo, Pb, Se, and U and the elements Al, Mg, Cu, Fe, and Zn in human hair samples of population living in the north of the Negev Desert in Israel was determined. The study population consisted of three subgroups: Jewish urban population, Bedouin urban population, and Bedouins living in unrecognized villages (the “dispersion”). The main focus is on the differences between these subgroups in an attempt to explore factors responsible for the variation in trace metal contents in hair samples. The results show that the level of several elements, particularly Ag, Mn, and Pb, in the female Bedouin group significantly differed from the other groups in the study. Exploring the reasons for these differences, we concluded that the lifestyle of those women is the main cause. The female Bedouin subgroup is exposed to heavy metals from kitchen utensils, jewelry, and makeup. Therefore, differences in the heavy metal concentration in the hair samples of this group were attributed to the traditional unique lifestyle and social behavior of the females in the Bedouin society.  相似文献   

3.
Taking into account the promising pharmacological actions of (Z)-2,3-bis(4-chlorophenylselanyl) prop-2-en-1-ol) (bis selenide), an organic compound containing the trace element selenium, and the constant search for drugs that improve the cognitive performance, the objective of the present study was to investigate whether bis selenide treatment ameliorates memory deficits induced by reserpine in rats. For this aim, male adult rats received a single subcutaneous injection of reserpine (1 mg/kg), a biogenic amine-depleting agent used to induce memory deficit. After 24 h, bis selenide at doses of 25 and 50 mg/kg was administered to rats by intragastric route, and 1 h later, the animals were submitted to behavior tasks. The effects of acute administration of bis selenide on memory were evaluated by social recognition, step-down passive avoidance, and object recognition paradigms. Exploratory and locomotor activities of rats were determined using the open-field test. Analysis of data revealed that the social memory disruption caused by reserpine was reversed by bis selenide at both doses. In addition, bis selenide, at the highest dose, prevented the memory deficit resulting from reserpine administration to rats in step-down passive avoidance and object recognition tasks. No significant alterations in locomotor and exploratory behaviors were found in animals treated with reserpine and/or bis selenide. Results obtained from distinct memory behavioral paradigms revealed that an acute treatment with bis selenide attenuated memory deficits induced by reserpine in rats.  相似文献   

4.
Proper trace element level and antioxidant enzyme activity are crucial for the brain in maintaining normal neurological functions. To our knowledge, alteration of lipid peroxidation status, trace element level, and antioxidant activity in the homogenates of brain cortex after cerebral ischemia in gerbil, however, has not been investigated so far. Male Mongolian gerbils were divided into control and ischemic subjects. Cerebral ischemia was induced by occlusion of the right middle cerebral artery and right common carotid artery for 1 h. Experimental results showed that a significant increase (P?<?0.01) of the malondialdehyde level was found in the ischemic brain as compared with the control group. Trace element analysis indicated that a remarkable elevation (P?<?0.01) of the level of iron (Fe), chromium (Cr), and a statistical decrease of selenium (Se) and zinc (Zn) (P?<?0.05) concentration were observed in the ischemic brain as compared with the control subject. No significant change (P?>?0.05) of the copper (Cu) level was found in both experimental groups. Additionally, antioxidant activity of superoxide dismutase (P?<?0.01) and catalase (P?<?0.05) was significantly decreased in the ischemic brain as compared with the control subject. Taking all results together, it is conceivable to manifest the experimental findings that cerebral ischemia not only may result in an enhanced oxidative stress but also may lead to further oxidative injury. Moreover, disturbance of trace element level combined with declined antioxidant activity seems to play a significant role in responsible for the etiology of cerebral ischemia.  相似文献   

5.
目的:研究微量元素锶对幼年自发性高血压大鼠(Spontaneously hypertensive rats,SHR)血压升高的预防作用并探讨其作用机制。方法:107只自发性高血压大鼠适应性喂养1周后,随机分为A组纯水对照组22只、B组锶水浓度3mg/L组22只、C组锶水浓度9mg/L组19只、D组锶水浓度18mg/L组22只,E组锶水浓度36mg/L组22只,普通饲料喂养12周。实验开始时测定基础血压,至结束时共测十次血压。实验开始及结束采血两次,检测肝、肾功能,Elisa法检测血清内皮素-1(endothelin-1,ET-1)、肾素(renin)、血管紧张素I(Iangiotensin-II)及去甲肾上腺素(noradrenalin,NA),免疫组化法检测主动脉核因子κB(nuclear factor-kappa B,NF-κB)、血管细胞黏附分子-1(vascular cell adhesion molecule-1,VCAM-1)、细胞间黏附分子-1(intercellular cell adhesion molecule-1,ICAM-1)的表达。结果:(1)SHR成年后,E组与A组相比表现出血压下降趋势(P<0.05);第十、十一、十二周时D、E组血压均显著低于A组(P<0.01);B、C组较A组也有不同程度下降;随锶水浓度增高血压呈逐渐下降的大体趋势,B-E组血压值低于A组(P<0.05,P<0.01);(2)锶水喂养后各组肝、肾功能指标及ET-1、renin、Ang-II、NA变化无明显差异(P>0.05);(3)锶水喂养后,B-E组主动脉NF-κB、VCAM-1;ICAM-1的积分光密度值(IOD)均显著低于A组(P<0.01),且随锶水浓度增高,NF-κB、VCAM-1、ICAM-1的表达呈递减趋势(P<0.01)。结论:微量元素锶可延缓SHR血压升高,减小血压波动,其对高血压的预防作用机制可能是由于抑制NF-κB经典通路,减少VCAM-1、ICAM-1等炎症介质的产生而减轻血管壁损害。  相似文献   

6.
Zinc deficiency has become a global problem affecting the developed and developing countries due to inhibitors in the diet which prevents its absorption or due to a very low concentration of bioavailable zinc in the diet. Being present in high concentration in the prostate and having diverse biological function, we investigated the effects of dietary zinc deficiency for 2 and 4 weeks on dorso-lateral and ventral prostate. Sixty prepubertal rats were divided into three groups: zinc control (ZC), pair fed (PF) and zinc deficient (ZD) and fed on 100 μg/g (zinc control and pair fed groups) and 1 μg/g (zinc deficient) diet. Zinc deficiency was associated with degenerative changes in dorso-lateral and ventral prostate as made evident by karyolysis, karyorhexis, cytoplasmolysis, loss of cellularisation, decreased intraluminar secretion and degeneration of fibromuscular stroma. In response, protein carbonyl, nitric oxide, acid phosphatase, 3β-hydroxysteroid dehydrogenase and 17β-hydroxysteroid dehydrogenase increased, exhibiting variable level of significance. Total protein and total zinc concentration in dorso-lateral and ventral prostate as well as in serum decreased (P?P?相似文献   

7.
Chronic liver failure induced by portocaval anastomosis (PCA) in Wistar rats resulted in a dramatic increase in histamine concentration in hypothalamus and a smaller, but clearly pronounced, elevation in the rest of brain. Between 10 and 120 days following surgery, shunted rats exhibited a histamine level 2.4- to 13-fold higher in hypothalamus and 1.5- to 2.5-fold higher in the rest of brain as compared to their control, sham-operated pairs. There were no significant changes in histamine concentration in the other examined tissues. The increase in brain histamine could not be attributed to the inhibition of its degradation, because activity of histamine N-methyltransferase remained unchanged for at least 40 days. Although the activity of histidine decarboxylase also remained unchanged when measured at a saturating concentration of L-histidine, the increase in histamine content in brain seems to be due to its enhanced synthesis brought about by increased availability of L-histidine in the tissue, as indicated by two to four times higher concentrations of this amino acid in PCA rats.  相似文献   

8.
SYNOPSIS. Administration of dexamethasone to rats infected with Trypanosoma lewisi resulted in the development of exceedingly large populations of trypanosomes which were fatal to their hosts. The elevated levels of parasitemia in treated rats early in infections were thought not to be a result of an increased reproductive rate. However, trypanosomes in treated rats 2 days postinfection did have a higher coefficient of variation in total length and a greater percentage of dividing forms than those observed from infected rats which were not given the drug. The course of infection may be markedly altered not only in intensity but also in length by this corticosteroid. It is suggested that dexamethasone administered at the levels recorded to rats infected with T. lewisi inhibits the production of ablastin and trypanocidal antibodies.  相似文献   

9.
单项氨基酸微量元素螯合物的研究   总被引:7,自引:0,他引:7  
利用有机溶剂沉淀法制备了高纯度的甘氨酸铜、甘氨酸锌及赖氨酸锌螯合物 ,以螯合率为指标考察了合成工艺的主要影响因素 ,确定了最佳的原料配比 ,pH值及反应时间和温度。并通过化学分析、原子吸收分光光度分析和红外光谱分析对螯合物进行了研究 ,确证了螯合物的生成。  相似文献   

10.
目的是通过研究微量元素对乙酰乳酸脱羧酶的影响,来提高乙酰乳酸脱羧酶的活力。在实验室阶段,考察了多种微量元素对乙酰乳酸脱羧酶发酵酶活力的影响,通过单因子实验确定出微量元素的最佳浓度,并通过正交试验来摸索最佳的组合。验证试验结果表明:四种微量元素在最佳浓度分别镁0.0025g/L、锰0.00025g/L、钼0.0025g/L、钡0.0005g/L的组合下,可使酶的激活率达199%以上。  相似文献   

11.
We investigated both the effect of levosimendan and the role of oxidant/antioxidant status and trace element levels in the pulmonary artery of rats. Fourteen male Wistar albino rats were randomly divided into two groups of seven animals each. Group 1 was not exposed to levosimendan and served as a control. Levosimendan (12 μg/kg) diluted in 10 ml 0.9 % NaCl was administered intraperitoneally to group 2. Animals of both groups were killed after 3 days, and their pulmonary arteries were harvested to determine changes in tissue oxidant/antioxidant status and trace element levels. The animals in both groups were killed 72 h after the levosimendan exposure treatment, and pulmonary arteries were harvested to determine levels of the lipid peroxidation product MDA and the antioxidant GSH as well as the decreased activity of antioxidant enzymes such as SOD, GSH-Px and CAT. It was found that MDA levels increased in pulmonary artery tissues of rats after levosimendan administration. The GSH level decreased in the pulmonary artery of rats after levosimendan treatment. Co, Mn, Fe, Cd and Pb levels were significantly higher (P < 0.001) and Mg, Zn and Cu levels significantly lower (P < 0.001) in the levosimendan group compared to the control group. These results suggest that levosimendan treatment caused an increase in free radical production and a decrease in antioxidant enzyme activity in the pulmonary artery of levosimendan-treated rats. It also caused a decrease or increase in the levels of many minerals in the pulmonary artery, which is an undesirable condition for normal pharmacological function.  相似文献   

12.
Biological Trace Element Research - The present study was considered to assess the protective effects of boron (B) on gentamicin-induced oxidative stress, proinflammatory cytokines, and...  相似文献   

13.
The present study was conducted to evaluate the serum copper, zinc, magnesium, and selenium levels in patients with subclinical hypothyroidism in the iodine-rich region of Ankara, Turkey. The effects of hormone replacement therapy on these elements were also studied in these patients. Basal levels of selenium and iron in patients were significantly lower than control group (67.7 +/- 10.4 vs. 83.7 +/- 17.3 microg/dl, p = 0.02; 55.7 +/- 38 vs 275.7 +/- 24, P = 0.03 microg/dl). Serum magnesium levels were significantly higher in patient group (2.16 +/- 0.31 vs 1.95 +/- 0.13 mg/dl, P < 0.0001). There was a correlation between selenium levels with hsCRP (r = -0.408, p = 0.007). HsCRP levels in patients with selenium levels <80 microg/l (n = 31) was significantly higher than hsCRP levels in patients with selenium levels >80 microg/l (n = 12; 1.99 +/- 1.0; 1.02 +/- 0.9, p = 0.014). None of these biochemical risk factors and trace elements have changed after euthyroidism in patients with SH when compared to pretreatment levels. Selenium deficiency may contribute to cardiovascular disease risk in these patients.  相似文献   

14.
一次性电击引起大鼠脑内突触结构可塑性变化的定量观察   总被引:1,自引:0,他引:1  
龚云 《动物学杂志》2000,35(1):21-24
运用电镜,对一次性电击引起大鼠脑内Gray Ⅰ型突触界面某些结构的变化进行了定量观察。在海马CA3区,突触后膜致密物质显著增厚(P〈0.05),突触间隙宽度极显著增宽(P〈0.01);在大脑皮层感觉运动区,突触界面曲率显著变大(P〈0.05)。突触界面弯曲类型无显著性差异。结果提示:一次性电击可以引起大鼠脑内突触界面结构发生可塑性变化。  相似文献   

15.
We have previously shown that the intrahippocampal microinjection of okadaic acid (OKA), a potent inhibitor of serine/threonine protein phosphatases, induces epileptic seizures, neuronal death, and the hyperphosphorylation of the NR2B subunit of the N-methyl-d-aspartate (NMDA) receptor. We administered OKA by reverse microdialysis in the hippocampus of awake and halothane-anesthetized rats, with simultaneous collection of microdialysis fractions and recording of the EEG activity, and subsequent histological analysis. OKA produced intense behavioral and persistent EEG seizure activity in the awake rats but not in the anesthetized animals, and did not significantly alter the extracellular concentration of glutamate and aspartate detected in the microdialysis fractions. One day after the experiment a remarkable neurodegeneration of CA1 hippocampal region was observed in both the awake and the anesthetized rats. We conclude that the OKA-induced epilepsy cannot be ascribed to increased extracellular glutamate, but to an increased sensitivity of NMDA receptor. We propose that halothane protected against the epilepsy because it blocks NMDA receptor overactivation, and that the neurodegeneration of CA1 region is independent of this overactivation and due probably to alterations of cytoskeletal proteins consequent to the OKA-induced hyperphosphorylation.  相似文献   

16.
Mycelium of Pisolithus arrhizus cultured on agar media containingcadmium dust (collected from industrial electrofilters) andon media without the dust was analysed by electron spectroscopicimaging (ESI) and electron energy loss spectroscopy (EELS) connectedwith the transmission electron microscope. Complementary investigationsof polysaccharide (PATAg) and cysteine rich protein localizationwere carried out. The analyses revealed abundant depositionof glycogen in the form of net-like material in the cytoplasmof the dust-supplemented mycelium, accompanied by increasedlevels of Ca. Heavy metals like Cd, Cu and Fe accumulated mainlyin electron opaque granules and in the outer pigmented layerof the cell wall, both characterized by the presence of polysaccharidesand cysteine-rich proteins.Copyright 1994, 1999 Academic Press Pisolithus arrhizus (Pers.) Rausch., mycorrhizal fungi, heavy metals, cytochemistry, element localization  相似文献   

17.
Paradichlorobenzene (pDCB) has been used as a space deodorant and moth repellant, as well as an intermediate in the chemical industry. Given its broad applications and high volatility, considerable concern exists regarding the adverse health effects of pDCB in the home and the workplace. In this study, changes in lipid peroxidation, antioxidants, and trace element levels in the liver and kidney of pDCB-treated mice were investigated to determine their roles in toxicity. Mice were orally gavaged once daily for seven consecutive days with pDCB (0 (corn oil control), 450, and 900 mg/kg). The level of malondialdehyde (MDA), an end product of lipid peroxidation, markedly increased in the high-dose pDCB group in both the liver and kidney compared with the control group. Changes in hepatic levels of reduced glutathione (GSH) in the pDCB groups were indistinguishable from the control group, while renal levels of reduced GSH in the high-dose pDCB group were significantly lowered in comparison to the control and the low-dose groups. Superoxide dismutase (SOD) activity in the liver of mice treated with pDCB showed a downward trend, whereas there was no consistent trend associated with changes in SOD activity in the kidney. Additionally, renal iron levels in the high-dose pDCB group were significantly decreased compared with the low-dose group and the controls, whereas hepatic iron content in the low-dose pDCB group was significantly lower compared with the controls. Selenium and zinc levels in the kidney were both significantly decreased in the high-dose pDCB group vs. the control and low-dose groups. There were no treatment-induced changes in copper levels in either the kidney or liver. However, a significant increase was found in the liver zinc/copper ratio in the high-dose pDCB group vs. the controls. In addition, blood zinc levels showed a downward trend with increased pDCB dosage. These results suggest that pDCB toxicity is mediated by oxidative damage and tissue-specific alterations in trace element levels both in the liver and the kidney of mice.  相似文献   

18.
In order to explore the associations between trace elements in dietary intake and the other three biological media (blood, urine, or feces) and inter-element interactions among the latter, we simultaneously collected 72-h diet duplicates, whole blood, and 72-h urine and feces from 120 free-living healthy males in China. Correlations among the toxic (cadmium [Cd], lead [Pb]), and nutritionally essential (zinc [Zn], copper [Cu], iron [Fe], manganese [Mn], selenium [Se], iodine [I]) elements were evaluated using Spearman rank correlation analysis based on analytical data determined by inductively coupled plasma-mass spectrometry. Dietary Cd intakes were highly correlated with the fecal Cd and blood Cd levels. Inverse correlations were found for Fe–Cd and Fe–Pb in both diet versus blood and diet versus feces. Cd–Zn and Cd–Se were significantly directly correlated in the urine and feces. Cd–Se and Pb–Se were negatively correlated in blood. In addition, there existed an extremely significant association between urinary Se and urinary I. Moreover, the other two highly direct correlations were found for Se–Fe and for I–Fe in urine. Improved knowledge regarding their mutual associations is considered to be of fundamental importance to understand more the complex interrelationships in trace element metabolism.  相似文献   

19.
This study is designed to determine the simultaneous effect of aluminium (Al) and melatonin (Mel) treatment in intact and ovariectomized (Ovx) female rats on oxidative stress and their inter-organ relationship in the kidney and liver. Al-treated rats received an intra-peritoneal injection of solution of aluminium lactate (0.575?mg Al/100?g of body weight, three times a week), during 12?weeks. Mel groups received intra-peritoneal injections of melatonin at a dose of 10?mg/kg/day, 5?days/week, during 12?weeks. The results of this study showed that Al treatment in female rats modifies homeostasis of glutathione and the antioxidant capacity of the rat liver and kidney. The alteration of glutathione homeostasis and oxidative status was not associated with an increased lipid peroxidation in both organs with the exception of the increase observed in the liver of Ovx rats. Al also induced modifications in the activity of some enzymes related to the glutathione cycle: GSH-Px in the liver and kidney and glutathione reductase only in the kidney. Al exposure decreased CAT activity in both the kidney and liver of intact and Ovx groups. The administration of Mel in the intact and castrated females treated with Al seems to reduce oxidative changes in the liver and kidney of intact and Ovx rats.  相似文献   

20.
The NGF content in each region of the brain of four-week-old rats was ranked in the decreasing order of cerebral cortex, hippocampus, cerebellum, midbrain/diencephalon, and pons/medulla ob-longata, and the NGF concentration, in the decreasing order of hippocampus, cerebral cortex, cerebellum, midbrain/diencephalon, and pons/medulla oblongata in both AFD and SFD groups. The NGF content and concentration in the cerebral cortex were about the same value at each age between those in the AFD and SFD groups. Those in the hippocampus were a little higher in the SFD group than in the AFD group at the ages of three and four weeks, unlike those in the other regions, where the values for the cerebellum, midbrain/diencephalon and pons/medulla oblongata tended to be somewhat higher in the AFD group than in the SFD group. The NGF concentrations in the hippocampus and cerebral cortex increased with growth: the concentration in the hippocampus at four weeks of age was about 4-fold of that at one week in the AFD group and about 5.7-fold of that at one week in the SFD group; and likewise the concentration in the cerebral cortex at four weeks of age was about 5.3-fold in the AFD group and about 7-fold in the SFD group. The NGF concentrations in the cerebellum decreased, and those in midbrain/diencephalon and pons/medulla oblongata hardly changed with growth in either AFD or SFD group. From these results NGF may have stronger implications for the neuronal growth in the hippocampus compared with those in the lower brain regions of the SFD rats.  相似文献   

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