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1.
The objective of this study was to evaluate the effects of a novel oxygen-coordinated niacin-bound chromium(III) complex (NBC) on the reproductive systems of male and female rats, the postnatal maturation and reproductive capacity of their offspring, and possible cumulative effects through multiple generations. Sprague-Dawley rats were maintained on feed containing NBC at dose levels of 0, 4, 15, or 60 ppm for 10 weeks prior to mating, during mating, and, for females through gestation and lactation, across two generations. For the parents (F0 and F1) and the offspring (F1 and F2a), reproductive parameters such as fertility and mating, gestation, parturition, litters, lactation, sexual maturity and development of offspring were assessed. Results from the current study indicated that dietary exposure of NBC to parental male and female rats of both (F0 and F1) the generations during the premating and mating periods, for both sexes, and during gestation and lactation in case of female rats, did not cause any significant incidence of mortality or abnormal clinical signs. Compared to respective controls, NBC exposure did not affect reproductive performance as evaluated by sexual maturity, fertility and mating, gestation, parturition, litter properties, lactation and development of the offspring. Based on the findings of this study, the parental as well as the offspring no-observed-adverse-effect level for NBC was determined to be greater than 60 ppm in diet or equivalent to 7.80 and 8.31 mg/kg body weight/day in male and female rats, respectively.  相似文献   

2.
Present study was undertaken to study the effect of 28-days exposure of female adult rats to cadmium (Cd) in drinking water @ 3, 10 and 30 parts per million (ppm) on myometrial responsiveness to different spasmogens and unravel the possible mechanism of alterations in myometrial activity. Cadmium and Ca2+ levels in blood and uterus were measured by atomic absorption spectroscopy while isometric tension in myometrial strips was measured using data acquisition system-based physiograph. Dose-dependent increase in levels of cadmium was observed in both blood and uterus while calcium was increased only in the uterus as compared to those in control. Significant increase in absolute tension and mean integral tension along with non-significant increase in frequency of myometrial contraction was observed in rats of Cd-treated groups. As compared to the control, cadmium decreased and increased the effects of calcium chloride, 80 mM KCl, histamine (0.1 μM) and oxytocin (10?2 IU/ml) in lower-dose (3 ppm) and higher-dose groups (10 and 30 ppm), respectively. Cadmium potentiated and inhibited the relaxant response to phenylephrine in myometrium of rats at lower-dose (3 ppm) and highest-dose (30 ppm) Cd-treated groups, respectively. Results of our study revealed that Cd accumulates in the myometrium of rats and alters its responsiveness to oxytocin, histamine, 80 mM KCl, calcium chloride and phenylephrine, and these effects are differentially mediated depending on levels of exposure possibly through voltage-dependent calcium channel (VDCC) and Ca2+-mimicking pathways.  相似文献   

3.
The objective of the study is to explore change and significance of IL-8, IL-4 and IL-10 in the pathogenesis of terminal Ileitis in SD rat. 60 male SD rats were divided into model group, suture group, and control group equally. The rats subjected to ileum-cecum side-to-side anastomosis in terminal ileum in model group, suture in terminal ileum in suture group, and the control group accepted no special treatment. The terminal ileum tissue which was 1–3 cm from anastomotic stoma was collected at 2 and 8 weeks after surgery in each group. The pathological slice was observed under microscope, and PCR was applied to detect the expression of IL-4, IL-8, and IL-10 at different times. Pathological result showed that neutrophils significantly increased in model group and suture group at 2nd week, showing acute inflammatory reaction; model group showed chronic inflammation at 8th week. The change of IL-8, IL-4, and IL-10 expression level at 2 weeks after surgery: The IL-8 expression level of SD rat terminal ileum tissue in model group was significantly higher than in control and suture groups (P < 0.01), and it was higher in suture group compared to control group (P < 0.01); the expression level of IL-4 in control group was higher than model and suture groups (P < 0.05); there was no statistical significance between model group and suture group (P = 0.363); the expression level of IL-10 in control group was higher than in model and suture groups (P < 0.01), and it was higher in suture group compared to model group (P < 0.01). The change of IL-8, IL-4, IL-10 expression level at 8 weeks after surgery: The expression level of IL-8 significantly decreased in model group, and there was no significantly difference between three groups (P > 0.05); the expression level of IL-4 was higher in model group and suture group compared to 2nd week; there was no significance between three groups (P < 0.05); the expression of IL-10 was higher in model group compared to 2nd week (P < 0.01), it was lower than control group and suture group (P < 0.01); there was no significant difference between suture group and control group (P > 0.05). The chronic terminal ileum model could be successfully established by ileum-cecum side-to-side anastomosis in terminal ileum in SD rats; IL-8 can induce the inflammatory reaction in terminal ileitis and chemokines aggregation and mediate inflammatory reaction by mediating other inflammatory factors; as a proinflammatory cytokine, IL-8 can inhibit IL-10; IL-10 and IL-4 can inhibit the inflammatory reaction of terminal ileum.  相似文献   

4.
Avoiding insulin resistance (IR) associated with aging might lengthen life span based on previous studies using caloric-restricted animals. We assessed whether consuming niacin-bound chromium (NBC) alone or in a formula containing other so-called “insulin sensitizers” would overcome various manifestations of aging and extend life span in Zucker Fatty Rats (ZFR). We compared many metabolic parameters of ZFR fed NBC alone (n = 12) or NBC in a unique formula (n = 10) to a control group (n = 10). In addition to NBC, the formula contained Allium sativum, Momordica charantia, Trigonella foenum-graecum and Gymnema sylvestre. The formula group received roughly 1/2 as much NBC daily as the NBC group. At week 44, all rats still lived, and no abnormalities in blood count (CBC), renal, or liver functions were found. In the two treatment groups compared to control, circulating glucose levels were significantly lower, with a trend toward lower HbA1C. Relatively elevated cholesterol and triglyceride concentrations occurred in the formula group. Compared to control, the NBC group had increased average lifespan (21.8%), median lifespan (14.1%), 30th percentile survival (19.6%), and maximum lifespan (22%). Despite similar beneficial effects on the glucose and blood pressure systems, a difference in aging was also found when the NBC group was compared to the formula group. When all rats in the other two groups had died, four in the NBC group continued to live at least a month longer. We attribute lack of a similar aging effect in the formula group to either lower dosing of NBC and/or that various ingredients in the formula counteracted the antiaging effect(s) of NBC.  相似文献   

5.
Excessive intake of sugars significantly elevates systolic blood pressure (SBP) in susceptible rats. Although the exact pathological mechanisms behind sugar-induced hypertension are uncertain and may be multiple, disturbances in the renin-angiotensin system (RAS) manifested by elevated circulating levels of angiotensin-2 may be involved. We attempted to confirm that the RAS was significantly involved in sugar-induced BP elevations and examined whether the ability of niacin-bound chromium (NBC) to ameliorate sugar-induced SBP elevations was due, at least in part, through effects on the RAS. Initially, 40 mature Sprague-Dawley rats (SD), male and female, were involved in the study comparing two methods to estimate rat blood pressure indirectly. Then 13 were selected to examine the effects of NBC on the RAS. All rats eventually ingested a diet heavy in sucrose (30% w/w). In addition to blood pressure readings, the following procedures were implemented: insulin and losartan challenges, evaluation of serum ACE activity, measurement of serum angiotensin-2 levels, blood chemistries, and LNAME challenge. While dietary sucrose raised SBP significantly in control, adding NBC to the treatment group lowered it back toward baseline. The treatment group was more sensitive to exogenous insulin challenge and showed decreased activity of the RAS estimated by less lowering of SBP after losartan challenge, decreased serum ACE (angiotensin-converting enzyme) activity, and lower levels of circulating angiotensin-2. The former two parameters showed statistical significance; and the latter, a trend toward statistical significance. A separate group receiving captopril served as a positive control and showed decreased ACE activity and circulating levels of angiotensin-2 compared to the control group. Our data suggest that the RAS plays a significant role in sugar-induced hypertension and that NBC lowers SBP, at least in part, via actions on the RAS. Other findings suggest that the NO system is important in sucrose-induced BP elevations as well.  相似文献   

6.
Although leptin has been shown to increase blood pressure (BP), it is however unclear if this increase can be prevented by exercise. This study therefore investigated the effect of leptin treatment with concurrent exercise on blood pressure (BP), sodium output, and endothelin-1 (ET-1) levels in normotensive rats. Male Sprague–Dawley rats weighing 250–270 g were divided into four groups consisting of a control group (n?=?6), leptin-treated (n?=?8), non-leptin-treated exercise group (n?=?8), and a leptin-treated exercise group (n?=?8). Leptin was given subcutaneously daily for 14 days (60 μg/kg/day). Animals were exercised on a treadmill for 30 min at a speed of 0.5 m/s and at 5° incline four times per week. Measurement of systolic blood pressure (SBP) and collection of urine samples for estimation of sodium and creatinine was done once a week. Serum samples were collected at the end of the experiment for determination of sodium, creatinine and ET-1. At day 14, mean SBP and serum ET-1 level in the leptin-treated group was significantly higher than that in the control group whereas mean SBP and serum ET-1 level was significantly lower in the leptin-treated exercise group than those in leptin-treated and control groups. Creatinine clearance, urinary sodium excretion, and urine output were not different between the four groups. Regular treadmill exercise prevents leptin-induced increases in SBP in rats, which might in part result from increased urinary sodium excretion and preventing the leptin-induced increases in serum ET-1 concentration.  相似文献   

7.
Carbon monoxide (CO) produced by incomplete combustion of hydrocarbons, has many toxic effects on different organs, especially the heart and brain that have greater demands for oxygen. The present study aimed to evaluate the protective effects of granulocyte colony stimulating factor (G-CSF) on apoptosis after CO poisoning in rats. Male Wistar rats were exposed to CO 1500 or 3000 ppm for 60 min. Single and multiple doses of G-CSF (10, 50, and 100 μg/kg) were administered to animals. After CO poisoning, carboxyhemoglobin concentration was measured, apoptotic cells were evaluated by TUNEL assay and caspase 3 activity was determined by immunofluorescence. Blood levels of carboxyhemoglobin significantly increased following exposure to both 1500 and 3000 ppm concentrations of CO. However, carboxyhemoglobin levels were significantly higher following exposure to CO 3000 ppm compared to CO 1500 ppm (p?<?0.05). Differences in caspase 3 activity between G-CSF and control groups were significant and G-CSF could decrease apoptosis following CO 3000 ppm poisoning (p?<?0.001). TUNEL assay showed that in rats treat with 5 doses of G-CSF 100 μg/kg, apoptosis was significantly ameliorated compared to control rats and sham (rats that were not exposed to CO) group (p?<?0.05). Concerning caspase 3 activity and apoptosis rate, the best results were found in rats exposed to 3000 ppm and treated with G-CSF 100 μg/kg. In this study, we confirmed that CO poisoning leads to cardiomyocytes apoptosis which could be significantly reduced by G-CSF treatment.  相似文献   

8.

Background

To evaluate association of 24 h–systolic blood pressure (SBP) variability and obstructive sleep apnea (OSA) as defined by the apnea-hypopnea index ≥5/h; and association of 24 h–SBP variability and prevalent cardiovascular disease (CVD) in OSA patients.

Methods

Participants underwent polysomongraphy to evaluate the presence of OSA, and 24 h–ambulatory blood pressure monitoring was applied to evaluate 24 h–SBP variability as indexed by weighted 24 h–standard deviation (SD) of SBP. Between-group differences were evaluated in participants with and without OSA. Participants with OSA were divided into high and low 24 h–SBP variability groups and between-group differences were evaluated.

Results

Mean age of 384 participants was 50 years old and 42.2% had OSA. Mean 24 h–systolic/diastolic BP were 130/78 mmHg, with mean weighted 24 h–SD of systolic/diastolic BP were 12.9/7.3 mmHg. Compared to those without OSA, OSA participants had higher clinic-, 24 h-, daytime- and nighttime-SBP, and weighted 24 h, daytime- and nighttime-SD of SBP. Age, prevalent CVD and OSA, usage of angiotensin converting enzyme inhibitor/angiotensin receptor blocker, calcium channel blocker and diuretic were significantly associated with 24 h–SBP variability. In OSA patients, compared to those with low variability, participants with high variability had higher weighted 24 h, daytime- and nighttime-SD of SBP. After adjusted for covariates including clinic-SBP and 24 h–SBP, per 1-SD increment weighted 24 h–SD of SBP was associated with 21% increased prevalent CVD.

Conclusions

Patients with newly-diagnosed OSA have higher 24 h–SBP variability compared to those without OSA; in OSA patients, increased 24 h–SBP variability is associated with increased prevalence of CVD.
  相似文献   

9.
The present study aims to examine the changes in the serum levels of trace elements before and after the operation in thyroid cancer patients. The study registered 50 individuals, of whom 25 were female and 25 were male. The patients were allocated to four groups: group 1: male thyroid cancer patients group (n = 15), group 2: female thyroid cancer patients group (n = 15), group 3: male control group (n = 10), group 4: female control group (n = 10). The subjects in groups 1 and 2 were the patients who were post-operatively diagnosed with a pathological malignancy in the thyroid tissue samples. Blood samples were collected from all subjects before the operation, immediately after the operation, and on the post-operative day 15. Additionally, thyroid tissue samples were taken from all subjects post-operatively. Some elements in the blood and tissue samples were determined using the atomic emission method. Zinc and selenium levels of groups 1 and 2 in the pre- and post-operative measurements were significantly lower than those in the control groups (p < 0.05), but were higher in the thyroid tissue (p < 0.05). Serum zinc and selenium levels measured in the subjects on the post-operative day 15 were similar to those measured in the controls. Our study show that changes in the serum and thyroid tissue levels of trace elements like zinc and selenium, which play a critical role in thyroid function, might be associated with the pathogenesis of thyroid cancer.  相似文献   

10.
Piwi-interacting RNAs (piRNAs) play a role in gene silencing of retrotransposons, maintenance of spermatogenesis and maturation in germlines. The piRNA and PIWI protein are essential for fertility. To reveal piRNA function associated with testosterone, we investigated the expression of piRNA and piwi protein in normal male rats and testosterone-treated rats. Normal Sprague–Dawley (SD) rats were randomly selected and sacrificed at neonatal to late adolescence stage stages (2, 9, 16, 20, 24, 28, 35, and 42 days, n = 6 each). Additional SD rats were divided into four groups: group 1 received weekly injections of testosterone enanthate (8 mg/100 g) during 1–3 weeks; group 2 during 3–5 weeks; group 3 during 1–5 weeks; and group 4 was the control (n = 20 each). These animals were sacrificed at an age of 60 days. We investigated piRNA, PIWI, and Ago3 protein levels using real-time PCR, Western blot, and immunohistochemistry in each group. In normal rats, PIWI protein and piRNA were expressed at P24. The expression of PIWI and piRNA gradually increased from adolescence to adulthood on Western blot, real-time PCR and immunohistochemistry. In testosterone-treated rats, the expression of PIWI protein was analyzed by Western blot and shown to be significantly increased in group 1 (neonatal to juvenile injection). In real-time PCR, the expression of piRNA after testosterone treatment was increased in all groups (G1 166.8 ± 2.7; G2 113.3 ± 4.6; G3 70.2 ± 1.5 vs. control, 32.87 ± 2.0, all p < 0.001). The expression of testosterone in adolescence induces the development of male genitourinary organs and spermatogenesis. At the same time, the sexual hormones may activate the piRNA and PIWI protein. Our data demonstrate that patterns of piRNA and PIWI expression are similar to the secretion pattern of testosterone, and that piRNA expression was increased after testosterone treatment. Therefore, testosterone may affect testis function through the regulation of piRNA expression in rats.  相似文献   

11.
Chromium (III) is an essential micronutrient required for normal protein, fat and carbohydrate metabolism, as well as helps insulin metabolize fat, turn protein into muscle and convert sugar into energy. A broad spectrum of research investigations including in vitro, in vivo and clinical studies demonstrated the beneficial effects of novel oxygen- coordinated niacin-bound chromium (III) complex (NBC) in promoting glucose-insulin sensitivity, lipid profile, cardioprotective ability and lean body mass. This study examined the long-term safety of NBC by orally administering either 0 or 25 ppm or the human equivalency dose of 1000 microg elemental chromium (III) as NBC per day for 52 consecutive weeks to male and female Sprague-Dawley rats. Animals of each group and each gender were sacrificed on 26, 39, or 52 weeks of treatment. Body weight, physical and ocular health, feed and water intake, selected organ weights as such and as a percentage of liver and brain weight, hepatic lipid peroxidation and DNA fragmentation, hematology and clinical chemistry, and histopathological evaluations were conducted. At 26, 39, or 52 weeks of treatment, body weight gain was significantly reduced by 7.7%, 8.1% and 14.9% in male rats, and 5.5%, 11.4% and 9.6% in female rats, respectively, in the NBC treatment groups. No significant changes were observed in hepatic lipid peroxidation and DNA fragmentation, hematology and clinical chemistry, and histopathological evaluation between control and NBC groups at these time points. These findings, thus far, are in agreement with the subchronic studies in terms of the safety of NBC.  相似文献   

12.
The effects of intermittent and stepwise administration of a β-adrenergic agonist, L644,969 on rat growth performance and skeletal muscle growth were investigated in two studies. In experiment 1, 34 juvenile male rats were randomly assigned to two treatment groups: (1) control, 0 ppm L644,969 for 21 days; (2) BL10, 10 ppm of L644,969 for 7 days, then 0 ppm L644,969 for another 7 days, plus 10 ppm of L644,969 for the final 7 days. L644,969 increased (P < 0.05) weight gain during the 7 day initial administration period. When L644,969 was withdrawn, no difference in weight gain was observed between the two groups. Re-administration of L644,969 after the withdrawal period increased (P < 0.01) weight gain up to 3 days of re-administration, but no effect was observed thereafter. In experiment 2, 18 juvenile female rats were divided into three groups: (1) control, 0 ppm L644,969 for 22 days; (2) BL10, 10 ppm L644,969 for 22 days; (3) BL10–60, 10 ppm L644,969 for 11 days, then 60 ppm L644,969 for another 11 days. Feeding 10 ppm L644,969 increased (P < 0.05) the rate of weight gain up to 11 days, but not thereafter. Raising the dose of L644,969 from 10 to 60 ppm increased body weight gain during the initial 8 day period, but no effect was observed thereafter. Weights of skeletal muscles and heart were significantly increased by 10 ppm L644,969. Raising the dose to 60 ppm increased the mean skeletal muscle weights without statistical significance. Muscular concentration of cAMP was significantly decreased by the long-term administration of L644,969. These results suggest that re-administration of the β-adrenergic agonists or increasing the dose of β-adrenergic agonists during the diminished response period could sustain the capability of the compound to enhance body weight gain.  相似文献   

13.
ObjectiveTo evaluate the effects of yttrium nitrate on the development of the parent, offspring and third generation of Sprague-Dawley (SD) rats by using a two-generation reproductive toxicity test.MethodsThe SD rats were randomly divided into 0 mg/kg group, 10.0 mg/kg group, 30.0 mg/kg group and 90.0 mg/kg group according to the different doses of yttrium nitrate administration. The reproductive toxicity of parent, offspring and third generation SD rats were compared.ResultsThe weight gains of F1a female rats and F2a female rats in the low-dose groups were significantly lower than those of the control groups (p < 0.05), the weight gains of F1a male rats in the medium-dose and high-dose groups were significantly lower than those of the control groups (p < 0.05), and the weight gains of F2a male rats in the low-dose, medium-dose and high-dose groups were significantly lower than those of the control groups (p < 0.05). In F0 male rats, the absolute weight and relative weight of the liver in the low-dose, middle-dose, and high-dose groups were significantly lower than those of the control group (p < 0.05). In F1b male rats, the absolute and relative weights of the liver in the medium-dose and high-dose groups were significantly lower than those of the control group (p < 0.05). In F2b male rats, the absolute and relative weights of the liver and spleen of the medium-dose and high-dose groups were significantly lower than those of the control group (p < 0.05). In F2a female rats, the absolute weight and relative weight of oviduct in the high-dose group were significantly lower than those in the control group (p < 0.05). The absolute and relative weights of lung, spleen, brain and uterus of F2b female rats in the high-dose group were higher than those of the control group (p < 0.05). But the pathological test results showed no hepatotoxicity. There was no statistically significant difference in sperm count and sperm motility between male rats in the yttrium nitrate administration groups and the control group (p > 0.05). There was no significant correlation between F0, F1a, F1b, F2a, F2b SD rats' reproductive organ lesions and the dose of yttrium nitrate.ConclusionYttrium nitrate at a dose of 90 mg/kg has no reproductive toxicity to two generations of SD rats, but 30.0 mg/kg dose of yttrium nitrate is toxic to the liver weight of male two generations of SD rats, but no hepatotoxicity.  相似文献   

14.
Thirty male and female (n?=?15 for each one) Markhoz newborn goat kids (aged 7?±?3 days) were distributed in a randomized block design in a 2?×?2?+?1 factorial arrangement: two levels of sodium selenite as a source of selenium (0.2 or 0.3 ppm Se), two levels of α-tocopherol acetate as a source of vitamin E (150 or 200 IU Vit E), and one control treatment with six repetitions per treatment (each replicate included three male and three female kids). Animals were fed daily by Se-Vit E-enriched milk (Se-Vit E treatments) or non-enriched milk (control treatment). Growth rate, hematology, and serum biological parameters were measured. The levels of serum albumin (P?<?0.01), serum globulin (P?<?0.05), total serum protein levels (P?<?0.01), erythrocyte counts (RBC) (P?<?0.001), hemoglobin (P?<?0.001), hematocrit (P?<?0.001), leukocyte counts (WBC) (P?<?0.001), IgA (P?<?0.05), IgG (P?<?0.01), and IgM (P?<?0.01) significantly differed among treatments, while no significant differences were observed for calcium, lymphocyte, neutrophil average daily gain and body weight among treatments. Kids feeding by enriched milk with 0.3 ppm Se and 200 IU Vit E had significantly higher serum total protein, globulin, RBC, IgA, IgG, and IgM compared to control and those fed by enriched milk to 0.2 ppm Se and 200 IU Vit E had significantly higher WBC counts.  相似文献   

15.
Bone marrow mesenchymal stem cells (MSCs) transplantation improved cardiac function and reduced myocardial fibrosis in both ischemic and non-ischemic cardiomyopathies. We evaluated the effects of repeated peripheral vein injection of MSCs on collagen network remodeling and myocardial TGF-β1, AT1, CYP11B2 (aldosterone synthase) gene expressions in a rat model of doxorubicin (DOX)-induced dilated cardiomyopathy (DCM). Thirty-eight out of 53 SD rats survived at 10 weeks post-DOX injection (2.5 mg/kg/week for 6 weeks, i.p.) were divided into DCM blank (without treatment, n = 12), DCM placebo (intravenous tail injection of 0.5 mL serum-free culture medium every other day for ten times, n = 13), and DCM plus MSCs group (intravenous tail injection of 5 × 106 MSCs dissolved in 0.5 mL serum-free culture medium every other day for 10 times, n = 13). Ten untreated rats served as normal controls. At 20 weeks after DOX injection, echocardiography, myocardial collagen content, myocardial expressions of types I and III collagen, TGF-β1, AT1, and CYP11B2 were compared among groups. At 20 weeks post-DOX injection, 8 rats (67 %) survived in DCM blank group, 9 rats (69 %) survived in DCM placebo group while 13 rats (100 %) survived in DCM plus MSCs group. Left ventricular end-diastolic diameter was significantly higher and ejection fraction was significantly lower in DCM blank and DCM placebo groups compared to normal control rats, which were significantly improved in DCM plus MSCs group (all p < 0.05 vs. DCM blank and DCM placebo groups). Moreover, myocardial collagen volume fraction, types I and III collagen, myocardial mRNA expressions of TGF-β1, AT1, CYP11B2, and collagen I/III ratio were all significantly lower in DCM plus MSCs group compared to DCM blank and DCM placebo groups (all p < 0.05). Repeated intravenous MSCs transplantation could improve cardiac function by attenuating myocardial collagen network remodeling possibly through downregulating renin–angiotensin–aldosterone system in DOX-induced DCM rats.  相似文献   

16.
To investigate the influence of chronic ethanol consumption on circulating thyroid hormone levels, male and female rats were given 20% ethanol as the only drinking solution daily for 8 weeks. Blood ethanol levels ranged 30–45 mg/L. In male rats serum T4 decreased from the initial mean ± SD value of 5.2±1.4 to3.0 ±0.7 μg/dl; T3 decreased from initial value of 97±14 to 66±11 ng/dl and rT3 decreased from initial value of 19±9 to 10±1 ng/dl after 8 weeks of ethanol ingestion. Under similar experimental conditions, female rats showed a significant decrease in serum T4 and rT3 levels; however, T3 levels decreased slightly but not significantly as compared to initial values. The results indicate adverse effect of chronic ethanol intake on serum thyroid hormone levels in rats.  相似文献   

17.
Binding and physico-chemical properties of sex steroid-binding protein (SBP) from blood serum and those of estrogen-binding components from liver cytosol of pubertal male and female species of clawed frog Xenopus laevis were studied. It was shown that SBP from both sex species of X. laevis specifically binds estradiol (E2) (Ka=5 . 10(6) M-1). Concentration of SBP binding sites for E2 is 7 . 10(-12) mole per mg of protein. Testosterone 5alpha-dihydrotestosterone and E2 effectively compete with [3H]-E2 for SBP binding sites. Hexestrol, progesterone and corticosterone are weak competitors; estrone and E2-17-hemisuccinate do not compete at all. The Strokes radius of SBP is 4.4 nm; sedimentation coefficient is 4.6S. Molecular weight of SBP is 88000; f/f0 is 1.5 SBP from male frog sera has been purified 8.6-fold with 13% yield. Gel-filtration of [3H]-E2 complexes with liver cytosol proteins shows that the livers of male and female frog X. laevis consol proteins shows that the livers of male and female frog X. laevis contain very low amounts of macromolecular component, which specifically binds E2; this component differs from serum SBP in size and in hormonal specificity. It is assumed that this component is a receptor for estrogens.  相似文献   

18.
Forty weaned male guinea pigs (Cavia porcellus) of 152.6?±?7.96 g mean body weight were divided into four equal groups and fed a common basal diet comprised of 25% ground cowpea (Vigna unguiculata) hay, 30% ground maize (Zea mays) grain, 22% ground gram (Cicer arietinum) grain, 9.5% deoiled rice (Oryza sativa) bran, 6% soybean (Glycine max) meal, 6% fish meal, 1.5% mineral mixture (without Se), and ascorbic acid at 200 mg/kg to meet their nutrient requirements along with 0, 0.1, 0.2, and 0.3 ppm of organic selenium (Se) in groups I, II, III, and IV, respectively. Experimental feeding lasted for a period of 10 weeks, during which, daily feed intake and weekly body weights were recorded. Intake and digestibility of dry matter, organic matter, ether extract, crude fiber, and nitrogen-free extract as well as uptake of calcium and phosphorus were similar (P?>?0.05) among the four groups. Feed:gain ratio was also similar (P?>?0.05) in the four groups. However, digestibility of crude protein was significantly (P?<?0.001) higher in group II supplemented with 0.1 ppm organic Se as compared to other three group. Intake and absorption of Se was significantly (P?<?0.001) higher in all the Se supplemented groups as compared to control group. Average daily gain (ADG) was significantly (P?<?0.05) higher in group II (3.16 g/day) and III (3.38 g/day) as compared to group I (2.88 g/day). However, ADG in group IV (supplemented 0.3 ppm organic Se) was significantly (P?<?0.05) lower (2.83 g/day) than group II and III, but comparable (P?>?0.05) to group I. Findings of the present experiment suggests that Se requirements of guinea pigs are ≥0.2 ppm, as supplementation of 0.1 ppm organic Se in the diet (having 0.1 ppm Se) not only enhanced their growth rate but also improved the protein utilization.  相似文献   

19.
Pineal glands secrets melatonin and various proteins and peptides which has many physiological functions. In keeping with this view, present experiment was conducted to know the effect of buffalo (Bubalus bubalis) pineal proteins (PP) at different dose level on fluoride-induced changes in plasma biochemicals and blood antioxidants enzymes in female rats. For this, we took 30 adult female Wistar rats (133–145 g body weights, BW) and divided into five groups (control, group I; 150 ppm fluoride (F), group II; F+ 50 µg pineal proteins, group III; F+ 100 µg PP, group IV; F+ 200 µg PP, group V). We administered fluoride (150 ppm, drinking water) and F+ pineal proteins at 50, 100, and 200 µg/kg BW, i.p. daily for 21 days. Blood samples were collected at the end of the experiments to estimate plasma glucose, proteins, F, lipid peroxidation (LPO), alkaline phosphatase (ALP), and acetyl cholinesterase (AChE) activity. Red blood cells (RBCs) were separated for analysis of LPO, AChE, catalase (CAT), superoxide dismutase (SOD), reduced glutathione (GSH), glutathione peroxidase (GPx), and glutathione reductase (GR) in different groups of animals. Total plasma glucose and protein level did not significantly change in F-treated rats. Plasma ALP and F level were significantly (p?<?0.05) high in group II as compared with control and groups III, IV, and V. Administration of PP at different dose level significantly (p?<?0.05) reduced the F concentration and ALP activity. Plasma and RBCs AChE activity was significantly (p?<?0.05) reduced in F-treated animals as compared with control rats and significantly (p?<?0.05) elevated on exogenous administration of PP (groups III and IV). Plasma and RBCs LPO level was significantly (p?<?0.05) high in F-alone-treated rats, and PP caused significant (p?<?0.05) reduction of LPO in groups IV and V. However, PP treatment in group IV brought better amelioration of F-induced high LPO than in groups III and V. At no dose level, PP-ameliorated F-induced depression of RBCs GSH, CAT, GR, and GPx level. Interestingly, SOD activity was elevated in dose-dependent manner at different dose level of PP in groups III, IV, and V than control and F-administered rats. These findings clearly indicate the beneficial effects of buffalo pineal proteins on fluoride-induced adverse changes in certain plasma biochemical and blood antioxidant systems of rats. It further indicates that PP has dose-dependent ameliorative function against F-induced adverse effects in plasma and blood.  相似文献   

20.
The objective of this study was to evaluate the efficiency of probiotics (Lactobacillus plantarum and Bacillus coagulans) against mercury-induced toxicity using a rat model. Mercury (Hg) is a widespread heavy metal and was shown to be associated with various diseases. Forty-eight adult male Wistar rats were randomly divided into six groups (control, mercury-only, each probiotic-only, and mercury plus each probiotic group). Hg-treated groups received 10 ppm mercuric chloride, and probiotic groups were administrated 1 × 109 CFU of probiotics daily for 48 days. Levels of mercury were determined using cold vapor technique, and some biochemical factors (list like glutathione peroxidase (GPx), superoxide dismutase (SOD), creatinine, urea, bilirubin, alanine transaminase (ALT), and aspartate transaminase (AST)) were measured to evaluate changes in oxidative stress. Oral administration of either probiotic was found to provide significant protection against mercury toxicity by decreasing the mercury level in the liver and kidney and preventing alterations in the levels of GPx and SOD. Probiotic treatment generated marked reduction in the levels of creatinine, urea, bilirubin, ALT, and AST indicating the positive influence of the probiotics on the adverse effects of Hg in the body.  相似文献   

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