The Roles of Melatonin and Vitamin E Plus Selenium in Prevention of Oxidative Stress Induced by Naloxone-Precipitated Withdrawal in Heroin-Addicted Rats

The therapeutic effects of melatonin or vitamin E plus Se (vE + Se) on the restrain of the heroin withdrawal-induced oxidative stress were studied. For this, rats were divided into ten groups. The rats were injected by fixed or variable doses of heroin for 16 consecutive days, and naloxone was given 1 h after the last heroin injection. One hour after naloxone administration, some groups were treated with melatonin or vE + Se. After 1 h this, blood samples were taken, and the levels of malondialdehyde (MDA) and reduced glutathione (GSH) in whole blood, ascorbic acid, α-tocopherol, retinol, β-carotene, nitrite, nitrate, and ceruloplasmin levels in the serum were measured. Our findings showed that, naloxone administration precipitated the heroin withdrawal. This also increased the level of MDA and decreased the levels of GSH in blood. Melatonin or vE + Se administration prevented the rise in MDA levels and increased the GSH levels. On the other hand, there were some significant differences between α-tocopherol, retinol, β-carotene, nitrite, nitrate, and ceruloplasmin levels of experimental groups. Results of present study showed that heroin withdrawal increased the lipid peroxidation and depressed endogenous antioxidative systems. Additionally, melatonin or vE + Se administrations prevented lipid peroxidation and augmented endogenous antioxidant defense systems.     

Pro-oxidant activity of aluminum in the rat hippocampus: gene expression of antioxidant enzymes after melatonin administration

Aluminum (Al)-induced pro-oxidant activity and the protective role of exogenous melatonin, as well as the mRNA levels of some antioxidant enzymes, were determined in the hippocampi of rats following administration of Al and/or melatonin. Two groups of male rats were intraperitoneally injected with Al (as Al lactate) or melatonin only, at doses of 7 and 10 mg/kg/day, respectively, for 11 weeks. During this period, a third group of animals received Al (7 mg/kg/day) plus melatonin (10 mg/kg/day). At the end of the treatment, hippocampus was removed and processed to examine the following oxidative stress markers: glutathione transferase (GST), reduced glutathione (GSH), oxidized glutathione (GSSG), superoxide dismutase (SOD), glutathione reductase (GR), glutathione peroxidase (GPx), catalase (CAT), thiobarbituric acid reactive substances (TBARS), as well as protein content. Gene expression of Cu-ZnSOD, MnSOD, GPx, and CAT was evaluated by real-time RT-PCR. On the other hand, Al, Fe, Mn, Cu, and Zn concentrations in hippocampus were also determined. The results show that Al exposure promotes oxidative stress in the rat hippocampus, with an increase in Al concentrations. The biochemical changes observed in this tissue indicate that Al acts as pro-oxidant agent, while melatonin exerts antioxidant action by increasing the mRNA levels of the antioxidant enzymes evaluated. The protective effects of melatonin, together with its low toxicity and its capacity to increase mRNA levels of antioxidant enzymes, suggest that this hormone might be administered as a potential supplement in the treatment of neurological disorders in which oxidative stress is involved.     

Potential Prevention and Treatment of Maifanite for Alzheimer's Disease Based on Behavior Test, Oxidative Stress Assay, and Trace Element Analysis in Hippocampus of Aβ(25–35)-Induced AD Rats

This study aimed to assess whether maifanite can improve the learning and memory, and antioxidant abilities of Alzheimer’s disease (AD) rats. The 70 rats were divided into seven groups: [A] normal control group, [B] AD model group, [C] sham group, [D] positive control group (donepezil), [E] low-dose maifanite group, [F] middle-dose maifanite group, [G] high-dose maifanite group. For [B], [D], [E], [F], and [G] groups, Aβ_(25–35) ventricle injection was carried out, then respective medicine were administered once a day for 60 consecutive days. The step-down and step-through test were used to measure learning and memory ability. The hippocampus levels of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and malondialdehyde (MDA) were assayed. The hippocampus contents of Al, Fe, Cu, Zn, Se, and Mn were analyzed by inductively coupled plasma–atomic emission spectrometer. Maifanite decreased the acquisition errors and the retention errors while prolonging the step-down latency, and decreased the number of electric shocks while prolonging the first latency of AD rats. Aβ_(25–35) ventricle injection initiated the decrease of SOD and GSH-Px activities and the increase of MDA content, and triggered the rise of Al, Fe, and Cu levels and the decline of Mn, Zn, and Se levels. The SOD and GSH-Px activities were enhanced followed by reduced MDA level, and the levels of Mn, Zn, and Se increased accompanied by Al, Fe, and Cu decreased in the maifanite treat groups. Maifanite could improve the learning and memory, and the antioxidant abilities of AD rats. Maifanite had the potential prevention and treatment for AD.     

Effects of Aluminum Exposure on Bone Mineral Density,Mineral, and Trace Elements in Rats

The purpose of the study was to investigate the effects of aluminum (Al) exposure on bone mineral elements, trace elements, and bone mineral density (BMD) in rats. One hundred Wistar rats were divided randomly into two groups. Experimental rats were given drinking water containing aluminum chloride (AlCl₃, 430 mg Al³⁺/L), whereas control rats were given distilled water for up to 150 days. Ten rats were sacrificed in each group every 30 days. The levels of Al, calcium (Ca), phosphorus (P), magnesium (Mg), zinc (Zn), iron (Fe), copper (Cu), manganese (Mn), selenium (Se), boron (B), and strontium (Sr) in bone and the BMD of femur were measured. Al-treated rats showed lower deposition of Ca, P, and Mg compared with control rats. Levels of trace elements (Zn, Fe, Cu, Mn, Se, B, and Sr) were significantly lower in the Al-treated group than in the control group from day 60, and the BMD of the femur metaphysis in the Al-treated group was significantly lower than in the control group on days 120 and 150. These findings indicate that long-term Al exposure reduces the levels of mineral and trace elements in bone. As a result, bone loss was induced (particularly in cancellous bone).     

Heroin affects purine nucleotides catabolism in rats in vivo

To investigate the effect of heroin on purine nucleotides catabolism, a rat model of heroin administration and withdrawal was established. Concentrations of uric acid, creatinine, and urea nitrogen in plasma and ADA in plasma, brain, liver, and small intestine were tested. When two heroin administration groups were compared with the control group, the concentrations of plasma uric acid and ADA in plasma, brain, liver, and small intestine increased, whereas the plasma urea nitrogen concentrations in two heroin administration groups and the plasma creatinine concentration in the 3-day heroin administration group did not increase. It seemed that heroin exposure for a short time did not affect renal clearance rate notably. When two withdrawal groups were compared with two heroin administration groups, the concentrations of plasma uric acid and ADA in liver and small intestine decreased, but there was no significant reduction in ADA concentrations of the brain, while the plasma ADA concentrations in the two withdrawal groups were significantly higher than those of two heroin administration groups. When the two withdrawal groups were compared with the control group, there was no significant difference in the concentrations of plasma uric acid and ADA in liver and small intestine, while the concentrations of ADA in plasma and brain were still higher than those of the control group. The results imply that heroin administration may enhance the catabolism of purine nucleotides in the brain and other tissues by increased concentration of ADA and the effect may last for a long time in the brain.     

Selenium improves the antioxidant ability against aluminium-induced oxidative stress in ryegrass roots

We investigated the role of selenium (Se) against aluminium (Al) stress in ryegrass by evaluating the growth responses and the antioxidant properties of plants cultured hydroponically with Al (0 or 0.2 mM) and selenite (0–10 µM Se). Al addition significantly reduced the yield and length of shoots and roots, and most Al was accumulated in the roots. Al also enhanced lipid peroxidation and activated the peroxidase (POD), ascorbate peroxidase (APX) and superoxide dismutase (SOD) enzymes in the roots. Se application up to 2 µM improved root growth and steadily decreased thiobarbituric acid reactive substances (TBARS) accumulation in plants treated with 0 and 0.2 mM Al. However, above 2 µM, Se induced stress in plants grown with or without Al. Significant changes in antioxidant enzymes activities were also found as a result of the added Se. At low Se addition levels POD was activated, whereas APX activity decreased irrespective of added Al. Furthermore, Se supplied up to 2 µM greatly decreased root SOD activity in Al-stressed plants. Our study provides evidence that Se alleviated the Al-induced oxidative stress in ryegrass roots through the enhancement of the spontaneous dismutation of superoxide radicals and the subsequent activation of POD enzyme.     

Trace mineral status in post menopausal women: impact of hormonal replacement therapy.

The risks of disturbances in trace mineral nutrition and metabolism are high following menopause. The aim of the study was to investigate the trace mineral status in postmenopausal women and the influence of hormonal replacement therapy on this status. Forty-four healthy postmenopausal women, aged 50-60 years old participated in the study. Eighteen were treated by combined hormonal replacement therapy (HRT) per os for at least two years, and 26 were untreated. Plasma trace mineral levels (Zn, Se, Cr, Mn, Cu), red blood cell antioxidant enzymes (Cu-Zn SOD, Se-GPX, Cu), urinary Zn, Cr, Mg, and Ca excretion were measured. Zinc, selenium and manganese plasma levels, activities of Cu-Zn-SOD and GSH-Px in erythrocytes were not statistically different between the two groups. The percentage of zinc plasma levels below the cut off of 10.7 micromol/L was higher in HRT treated group than in untreated one, whereas zinc excretion was reduced. Plasma copper concentrations were higher in women treated by HRT, whereas erythrocyte copper levels were not modified. Plasma chromium concentrations were significantly higher in women receiving HRT and urinary Cr excretion was decreased. The HRT group also exhibited lower losses of urinary zinc and magnesium than untreated women. These data suggest that hormonal replacement therapy provides beneficial effects on trace mineral status related to menopause.     

Analysis of the Relationship Between Hemorheologic Parameters,Aluminum, Manganese,and Selenium in Smokers

Smoking is a significant risk factor in fatal pathologies including cardio-cerebrovascular and respiratory diseases. Aluminum (Al) is a toxic element without known biological function, but with recognized toxic effects. Manganese (Mn) and selenium (Se) are essential trace elements involved in cellular antioxidant defense mechanisms. Al, Mn, and Se carry out their metabolic activities via blood flow and tissue oxygenation. The structure and number of red blood cells (RBC) play important role in tissue oxygenation throughout blood flow. Increased hematocrit (Hct) as a result of probable hypoxia induces disturbed blood flow, RBC aggregation (RBC Agg), RBC deformability index (Tk), and oxygen delivery index (ODI). Therefore, we aimed to investigate the effects of altered Al, Mn, and Se levels on number, structure, and function of RBCs (Hct, blood and plasma viscosity (BV and PV, respectively), RBC Agg, Tk, ODI) in smokers without diagnosis of chronic obstructive pulmonary disease (COPD) in a study group (n = 128) categorized as ex-smokers (ES), smokers (S), and healthy controls (HC). Elements were analyzed in serum using ICP-OES. BV and PV were measured via Brookfield and Harkness viscometers at 37 °C, respectively. Smokers had statistically higher serum Al and Mn levels, BV, RBC, Hgb, Hct, PV, fibrinogen, RBC Agg, Tk₄₅, and pulmonary blood flow rate, but lower serum Se levels and ODI₄₅ values versus HC. In conclusion, increased Al, Mn, and hemorheological parameters and decreased Se and ODI₄₅ might result from inflammatory response in defense mechanism in smokers without diagnosis of COPD. Our results point out that serum Al, Mn, and Se with hemorheological parameters may be beneficial markers of tissue oxygenation and defense mechanism before the clinic onset of COPD in smokers.

     

Serum concentrations of macro and trace elements in heroin addicts of the Canary islands

Na, K, Ca, Mg, P, Fe, Cu, Zn and Se concentrations were determined in the serum of 106 heroin addicts and were compared with the concentrations obtained in a control group formed of 186 apparently healthy individuals. Heroin addicts displayed K and Se mean concentrations lower (p < 0.05), and Na, Mg, P mean concentrations and a Cu/Zn ratio higher (p < 0.05) than those mean values observed in the control group. The Mg and P concentrations in the serum of heroin addicts tended to normalize when age increased. The heroin addicts included in the methadone maintenance treatment program had higher serum mean concentrations of K and Mg than the heroin addicts in the detoxification process. The Na, K and Mg concentrations displayed highly significant correlations, with a different behavior for the heroin addicts group and the control group. When applying factor analysis and representing the scores of the first and second factors, the heroin addicts tended to differentiation from the control group. However, methadone substitution treatment was not able to normalize these concentrations.     

Ameliorative action of melatonin on oxidative damage induced by atrazine toxicity in rat erythrocytes

Excessive generation of reactive oxygen species (ROS) can induce oxidative damage to vital cellular molecules and structures including DNA, lipids, proteins, and membranes. Recently, melatonin has attracted attention because of their free radical scavenging and antioxidant properties. The aim of this study was to evaluate the possible protective role of melatonin against atrazine-induced oxidative stress in rat erythrocytes in vivo. Adult male albino rats of Wistar strain were randomly divided into four groups. Control group received isotonic saline; melatonin (10 mg/kg bw/day) group; atrazine (300 mg/kg of bw/day) group; atrazine + melatonin group. Oral administration of atrazine and melatonin was given daily for 21 days. Oxidative stress was assessed by determining the glutathione (GSH) and malondialdehyde (MDA) level, and alteration in antioxidant enzymes such as superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), glutathione-S-transferase (GST), and glucose-6-phosphate dehydrogenase (G-6-PD) in the erythrocytes of normal and experimental animals. A significant increase in the MDA levels and decrease in the GSH was observed in the atrazine treated animals (P < 0.05). Also, significant increase in the activities of SOD, CAT, GPx, and GST were observed in atrazine treated group compared to controls (P < 0.05). Moreover, significant decrease in protein, total lipids, cholesterol, and phospholipid content in erythrocyte membrane were demonstrated in atrazine treated rats. Administration of atrazine significantly inhibits the activities of G-6-PD and membrane ATPases such as Na(+)/K(+)-ATPase, Mg(2+)-ATPase, and Ca(2+)-ATPase (P < 0.05). Scanning electron microscopic (SEM) examination of erythrocytes revealed morphological alterations in the erythrocytes of atrazine treated rats. Furthermore, supplementation of melatonin significantly modulates the atrazine-induced changes in LPO level, total lipids, total ATPases, GSH, and antioxidant enzymes in erythrocytes. In conclusion, the increase in oxidative stress markers and the concomitant alterations in antioxidant defense system indicate the role of oxidative stress in erythrocytes of atrazine-induced damage. Moreover, melatonin shows a protective role against atrazine-induced oxidative damage in rat erythrocytes.     

Alterations of plasma magnesium,copper, zinc,iron and selenium concentrations and some related erythrocyte antioxidant enzyme activities in patients with Alzheimer’s disease

The aim of the present study is to evaluate the status of plasma essential trace elements magnesium (Mg), copper (Cu), zinc (Zn), iron (Fe) and selenium (Se) concentrations and their some related antioxidant enzyme activities, erythrocyte glutathione peroxidase (GPx), superoxide dismutase (SOD), and catalase (CAT) activities in patients with Alzheimer’s disease (AD). Fifty patients with AD and fifty healthy control subjects were included in this study. Plasma Cu and Zn concentrations by atomic absorption spectrometry (AAS), plasma Mg and Fe concentrations by spectrophotometric methods and plasma Se concentrations by graphite furnace AAS were determined. Erythrocyte GPx, SOD and CAT activities were measured by spectrophotometric methods. Plasma Mg, Cu, Zn, Fe and Se levels and erythrocyte GPx, SOD and CAT activities were found to be significantly lower in patients with AD compared with controls. These results suggest that alterations in essential trace elements and their related enzymes may play a role in the etiopathogenesis of AD. Also, there is a defect in the antioxidant defense system, which may lead to oxidative damage in patients with AD. The changes in antioxidant enzyme activities may be secondary to the alterations in their cofactor concentrations.     

人工饲养与野生川金丝猴体毛10种微量元素的含量及比较

测定了秦岭人工饲养(10只)和野生(14只)川金丝猴体毛中的10种微量元素含量。锌、铁、铜、钙、镁5种元素采用火焰原子吸收法;锰、铬、铅采用石墨炉原子吸收法;铝采用等离子光谱;硒经硝解后采用原子吸收法测定。结果表明,铬、锰、镁、铅、锌和硒的含量,人工猴极显著或显著高于野生猴;铁含量,人工猴极显著低于野生猴;钙、铜和铝的含量,人工猴与野生猴无显著差异。以人类毛发10种微量元素的正常范围为参照,人工猴铅、铬、锰与锌4种含量均显著超出正常范围的上限,属于严重超量。这可能与金丝猴饲养过程中添加营养制剂有关。     

Selenium supplementation and exercise: effect on oxidant stress in overweight adults

Both obesity and acute high‐intensity exercise increase oxidant stress levels. This study investigates whether selenium (Se) supplementation could be a potential effective therapy to reduce obesity‐associated oxidant stress and exercise‐induced oxidant stress. Ten normal‐weight (NW) (22.80 ± 0.41 kg/m²) and ten overweight (OW) healthy subjects (28.00 ± 0.81 kg/m²) were assessed during a randomized double‐blind Se supplementation study (200 µg sodium selenite/day for 3 weeks) with a 3‐week placebo control and inversion of treatment periods. Blood levels of lipid hydroperoxide (LH), superoxide dismutase (SOD), erythrocyte glutathione (GSH), and total antioxidant status (TAS), were measured at rest, pre‐, and postexercise (30 min 70% VO₂ max before and after treatment (pretreatment (week 0 and 12) and post‐treatment (week 3 or 15)). At rest, compared to placebo, Se supplementation had no significant effect on LH, SOD, GSH, and TAS levels. However, Se supplementation decreased LH levels in the OW group, immediately postexercise (?0.25 ± 0.12 µmol/l, P = 0.05) compared to placebo treatment. Postexercise, with or without Se supplementation, no changes in TAS, SOD, and GSH levels were observed in both the NW and OW group. This study has highlighted a potential benefit of Se in reducing LH levels postexercise in OW individuals. Given that oxidant stress is a predictor of coronary events, it is imperative to better understand oxidant stress‐related responses to lifestyle factors (in particular “high‐risk” population groups) and potential antioxidant therapy.     

Serum selenium levels and oxidative balance as differential markers in hepatic damage caused by alcohol

Aims

Antioxidant system abnormalities have been associated with ethanol consumption. This study examines the effects of chronic ethanol consumption on oxidative balance, including selenium (Se) levels in alcoholic patients with or without liver disease, and if these measurements could be indicative of liver disease.

Main methods

Serum Se levels, antioxidant enzymes' activities, malondialdehyde (MDA) and protein carbonyl (PC) were determined in three groups of patients: alcoholics without liver disease, alcoholics with liver disease, and non-alcoholics with liver disease; and in healthy volunteers.

Key findings

Serum Se levels were lower in alcoholic patients and in patients affected by liver disease and especially lower in the alcoholic liver disease group. These values were correlated with the activity of glutathione peroxidase (GPx), the antioxidant selenoprotein. The antioxidant activities of the glutathione reductase (GR) and superoxide dismutase (SOD) were also lower in the three non-healthy groups. However, GR activity decreased and SOD activity increased in the non-alcoholic liver disease group versus alcoholic groups. Higher concentrations of PC in serum were found in non-healthy groups and were higher in alcoholic patients who also showed higher MDA levels. The highest MDA and PC levels were found in the alcoholic liver disease group.

Significance

We conclude that serum Se levels are drastically decreased in alcoholic liver disease patients, showing that this element has a direct correlation with GPx activity, and lipid oxidation, suggesting that the serum Se/MDA ratio could be an indicator of hepatic damage caused by alcohol consumption, and pointing to Se as a possible antioxidant therapy.     

Oxidative stress in heroin administered mice and natural antioxidants protection

The oxidative stress of heroin administered mice via intraperitoneal injection, and the therapeutic effects of exogenous antioxidants on the restrain of the oxidative damage of biomolecules and withdrawal syndrome were studied. After administered with heroin, mice showed decrease of total antioxidant capacity in blood, increase of reactive oxygen species production in white blood cells, and increase of oxidative damages of protein and lipid in brain and liver, but not in heart. On the other hand, exogenous antioxidants could restrain the oxidative stress, even alleviate withdrawal syndrome.     

Coadministration of melatonin and estradiol in rats: effects on oxidant status.

This study was designed to investigate the effects of melatonin and estradiol (E2) on lipid peroxidation and antioxidant defense enzymes in blood and liver tissue when administered in vivo. Wistar albino rats were divided into three experimental groups and treated with either estradiol (25 mg/kg bw, s.c.), melatonin (i. p.), or melatonin plus E2, whereas control animals had diluent injections only. Melatonin was given 10 mg/kg bw x 2 intraperitoneally 30 min before and 60 min after E2 treatment to the melatonin plus E2 group. Animals were sacrificed three hours after the estradiol injection, and their blood and liver tissues were prepared for biochemical analyses. Tissue malondialdehyde (MDA) levels and antioxidant enzyme activities--superoxide dismutase (SOD) and glutathione peroxidase (GPx)--were determined in the postmitochondrial fraction, and the results were compared. Estradiol injection caused significant increases in both MDA levels and GPx activity in liver. When melatonin was administered in combination with E2, the effect of estradiol on MDA levels was abolished. A significant decrement in SOD activity occurred in melatonin-treated animals. GPx activity in the blood of E2 plus melatonin-injected animals was significantly higher than those in control animals. Melatonin-treated animals exhibited relatively lower levels of SOD activity than those from the control and E2 plus melatonin groups. This indicates that estradiol could exert oxidant action resulting in an increment in tissue malondialdehyde levels. Enhanced activity of GPx in both liver and blood following melatonin injection may indicate the contribution of this neurohormone on the antioxidant defense.     

Protective Role of Melatonin on Oxidative Stress Status and RNA Expression in Cerebral Cortex and Cerebellum of AβPP Transgenic Mice After Chronic Exposure to Aluminum

Aluminum (Al) has been associated with pro-oxidant effects, as well as with various serious neurodegenerative diseases such as Alzheimer’s disease (AD). On the other hand, melatonin (Mel) is a known antioxidant, which can directly act as free radical scavenger, or indirectly by inducing the expression of some genes linked to the antioxidant defense. In this study, 5-month-old AßPP female transgenic (Tg2576) (Tg) and wild-type mice were fed with Al lactate supplemented in the diet (1 mg Al/g diet). Concurrently, animals received oral Mel (10 mg/kg) until the end of the study at 11 months of age. Four treatment groups were included for both Tg and wild-type mice: control, Al only, Mel only, and Al + Mel. At the end of the treatment period, cortex and cerebellum were removed and processed to examine the following oxidative stress markers: reduced glutathione, oxidized glutathione, cytosolic Cu–Zn superoxide dismutase (SOD1), glutathione reductase (GR), glutathione peroxidase, catalase (CAT), and thiobarbituric acid reactive substances. Moreover, the gene expression of SOD1, GR, and CAT was evaluated by real-time RT-PCR. The biochemical changes observed in cortex and cerebellum suggest that Al acted as a pro-oxidant agent. Melatonin exerted an antioxidant action by increasing the mRNA levels of the enzymes SOD1, CAT, and GR evaluated in presence of Al and Mel, independently on the animal model.     

Antioxidative metabolism in down syndrome

Down syndrome is the most common cause of mental retardation, affecting 1 in 700–800 liveborn infants. Although numerous biochemical abnormalities accompanying the syndrome have not yet been completely clarified, the antioxidant defense system enzymes have shown to be altered due to increased gene dosage on chromosome 21 and overproduction of superoxide dismutase (SOD-1 or Cu/Zn SOD). The purpose of this study was to investigate the activities of SOD-1 and glutathione peroxidase (GSH-Px) enzymes and the levels of their cofactors zinc (Zn), copper (Cu) and selenium (Se) in plasma of 20 Down syndrome patients. In comparison with age and sex-matched controls (n=15), plasma GSH-Px, SOD, and Cu levels were significantly decreased in the patient group, but Zn and Se concentrations remained unchanged. This study was presented as a poster in 29th Annual Meeting of European Society of Human Genetics held in Genoa in May, 1997.     

Trace element contents in hair of residents from Harbin (China), Medan (Indonesia), and Tokushima (Japan)

The concentrations of 19 trace element in hair samples from 1273 residents of Harbin (China), Medan (Indonesia), and Tokushima (Japan) were measured by inductively coupled plasma emission spectrometry. The mean concentrations of Ba, Ca, and Se were significantly higher in the Harbin hair samples when compared to those from Medan, but Al, B, Cu, Fe, Mn, Na, Pb, Ti, Zn, and K were significantly higher in Medan than in Harbin hair samples. The differences in the mean concentrations of As, Cr, Mg, P, Sn, and Sr between the Medan and Harbin lots were not significant. In the Tokushima hair samples, Na and K were significantly higher, but As, B, Ba, Ca, Cr, Mg, Mn, Pb, Sn, Sr, and Se were significantly lower than in the Harbin hair samples. The differences in the mean concentrations of Al, Cu, Fe, P, Ti, and Zn between Harbin and Tokushima were not significant. In the Medan hair samples, Al, As, B, Ba, Ca, Cr, Cu, Fe, Mg, Mn, Pb, Sn, Sr, Ti, and Zn were significantly higher, but P and Se were significantly lower than in Tokushima hair samples. Differences in mean concentrations of Na and K between Tokushima and Medan were not significant.     

氮磷肥对茶树锌硒等中微量元素吸收与分配的影响

锌（Zn）和硒（Se）及其他中微量元素（铝Al,钙Ca,铁Fe,铜Cu,锰Mn）是茶叶品质的重要指标,但茶树吸收Zn、Se能力及氮（N）磷（P）肥影响中微量元素吸收与分配的过程尚不清楚。以红壤丘陵区福鼎大白茶树为研究对象,开展Zn+Se、Zn+Se+N、Zn+Se+P、Zn+Se+N+P和对照共5种处理3次重复随机化区组试验,处理第3年春季分茶叶、成熟叶、吸收根、运输根和储藏根采集植物样品,测定其元素含量。结果表明,茶树地上和地下器官Zn和Se及其他中微量元素对N、P、Zn、Se添加的响应具分异性。与对照相比,茶树地上和地下器官Zn和Se含量均显著增加,与Zn+Se相比,施N和/或P肥仅显著提高茶叶和成熟叶Se含量（P<0.05）;与对照相比,施肥处理均显著提高吸收根和运输根Al、Fe含量以及储藏根Cu含量;运输根Mn含量表现为Zn+Se+N、Zn+Se+P、Zn+Se+N+P显著高于对照,储藏根Mn含量为Zn+Se+N+P显著高于其他处理;茶树各器官Ca含量对施肥处理无显著响应。此外,茶叶和成熟叶的Zn含量与吸收根显著正相关,而Se含量则与储藏根显著正相关。茶树具有吸收和积累Zn和Se的能力,而施N、P肥有助于提高茶叶Se含量,研究结果为红壤丘陵区培育高品质锌硒茶及营建生态高值茶园提供了依据。