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1.
南板蓝根氨基酸的分析   总被引：5，自引：0，他引：5  
利用氨基酸分析仪对南板蓝根氨基酸进行分离测定，证实其含有脯氨酸、甘氨酸、苏氨酸、蛋氨酸、丙氨酸、天门冬氨酸、谷氨酸、半胱氨酸、苯丙氨酸、酪氨酸、缬氨酸、异亮氨酸、亮氨酸、丝氨酸等十四种氨基酸，但未发现精氨酸、赖氨酸和组氨酸。  相似文献   

2.
The aim of this study was to investigate the effect of short intense exercise on plasma amino acid concentrations in trotters and to test the repeatability of plasma amino acids concentration in samples obtained on two independent days under field conditions. Plasma amino acid concentrations were analysed in blood samples of 36 standardbred trotters before and after intense exercise over a distance of 2000 m. Sampling was repeated in 20 horses after 35 days. Exercise intensity was estimated from post‐exercise lactate levels. Horses were divided in two groups according to a cut‐off lactate concentration at 15 mmol/l. The plasma concentrations of alanine, aspartate, glutamate, isoleucine, leucine, lysine and taurine increased and arginine, asparagine, citrulline, glutamine, glycine, histidine, methionine, serine, tryptophan and 3‐methylhistidine decreased after exercise. Ornithine, threonine, tyrosine, phenylalanine and valine concentrations remained constant. Higher intensity of exercise significantly decreased tryptophan and increased taurine concentrations. Sampling day had a significant effect on the absolute pre‐ and post‐exercise amino acid concentrations. Exercise had a significant influence on the concentrations of most plasma amino acids in trotters. These changes could reflect shifts between the free amino acid compartments, but there were also some indications for muscle catabolism. The amino acid supply of sporting horses could be of specific significance for maintaining muscle integrity and for the improvement of post‐exercise recovery of competition horses.  相似文献   

3.

Background

The branched chain amino acid leucine is a potent stimulator of insulin secretion. Used in combination with glucose it can increase the insulin response and the post exercise re-synthesis of glycogen in man. Decreased plasma amino acid concentrations have been reported after intravenous or per oral administration of leucine in man as well as after a single per oral dose in horses. In man, a negative correlation between the insulin response and the concentrations of isoleucine, valine and methionine have been shown but results from horses are lacking. This study aims to determine the effect of repeated per oral administration with a mixture of glucose and leucine on the free amino acid profile and the insulin response in horses after glycogen-depleting exercise.

Methods

In a crossover design, after a glycogen depleting exercise, twelve Standardbred trotters received either repeated oral boluses of glucose, 1 g/kg body weight (BW) at 0, 2 and 4 h with addition of leucine 0.1 g/kg BW at 0 and 4 h (GLU+LEU), or repeated boluses of water at 0, 2 and 4 h (CON). Blood samples for analysis of glucose, insulin and amino acid concentrations were collected prior to exercise and over a 6 h post-exercise period. A mixed model approach was used for the statistical analyses.

Results

Plasma leucine, isoleucine, valine, tyrosine and phenylalanine concentrations increased after exercise. Post-exercise serum glucose and plasma insulin response were significantly higher in the GLU+LEU treatment compared to the CON treatment. Plasma leucine concentrations increased after supplementation. During the post-exercise period isoleucine, valine and methionine concentrations decreased in both treatments but were significantly lower in the GLU+LEU treatment. There was no correlation between the insulin response and the response in plasma leucine, isoleucine, valine and methionine.

Conclusions

Repeated post-exercise administration with a mixture of leucine and glucose caused a marked insulin response and altered the plasma amino acid profile in horses in a similar manner as described in man. However, the decreases seen in plasma amino acids in horses seem to be related more to an effect of leucine and not to the insulin response as seen in man.  相似文献   

4.
Few data are available on post-prandial changes of plasma amino acids (AAs) in horses and on the repeatability and the individual variance on different sampling days. The objective of the present study was to measure pre- and post-prandial concentrations of plasma AA in 10 yearling horses. Blood samples were taken on days 1 and 40 of the study before feeding of hay, oats and soya meal and over an 8 h post-prandial period in 2-h intervals. The plasma AAs were measured by high-pressure liquid chromatography after ortho-phthalaldehyde derivatization. Mean fasting concentrations of the AAs were not significantly influenced by the individuum and sampling day. Repeatability of the fasting AA levels in the individual horses on two different sampling days was only found for histidine, 3-methylhistidine, methionine, tryptophan and taurine. While the absolute post-prandial AA concentrations differed between sampling days, the relative changes were comparable. All AA concentrations except 3-methylhistidine increased after feeding by 13% to more than 200% of their fasting values if the combined data of both days were analysed. Four hours after feeding the concentrations of arginine, asparagine, lysine, leucine, isoleucine and threonine, decreased more than 20%. Histidine, methionine, phenylalanine, valine, tryptophan, glutamine, glycine, tyrosine and taurine concentrations decreased by less than 20%. Concentrations of aspartic acid, glutamic acid, ornithine, serine and citrulline remained elevated. Most AA approached the fasting concentrations at 8 h, only glycine increased between 6 and 8 h after meal and 3-methyl-histidine concentrations were constant throughout the entire period. In conclusion, the pre-prandial plasma AA in horses appeared less influenced by individuum or sampling day than post-prandial plasma AA concentrations. Therefore, plasma AA concentrations should be interpreted only under well-defined conditions, especially regarding the feeding regimen.  相似文献   

5.
The amino acid requirements of the growing chick have been determined using a diet based on soybean meal and maize meal. The diet contained 18% protein (N% x 6.25, dry matter basis) made up to 14% contributed by conventional ingredients and 4% protein equivalent in the form of amino acids. Starting with a diet formulated to meet the reference levels recommended by Dean and Scott (1965) a programme of experiments was carried out to improve this amino acid balance. The results indicated that the growing chick requires not more than 0.53% threonine, 0.61% glycine, 0.79% valine, 0.62% isoleucine, 1.34% leucine, 0.75% phenylalanine (or 1.3% phenylalanine plus tyrosine), 0.85 % lysine, 0.4% histidine, 0.86% arginine, 0.17% tryptophan and 0.39% methionine (or 0.79% methionine plus cystine).  相似文献   

6.
The influence of protein deficiency, rehabilitation and total starvation on the free amino acid levels in the blood plasma of pigs has been investigated. It was found that the concentration of most amino acids was reduced during protein deficiency. The levels of leucine, isoleucine and valine were diminished by the greatest proportion, followed by threonine, tyrosine and citrulline. During the first few weeks of protein deficiency the levels of lysine, histidine and arginine were slightly increased, but later decreased below control values. Concentrations of glycine and alanine were altered in a similar way except that the initial increase was much more pronounced. The concentrations of most of these amino acids returned to control levels after rehabilitation. Total starvation led to an increase in concentration of leucine, isoleucine, valine, threonine and to a smaller extent phenylalanine, lysine, citrulline and arginine. The concentration of glycine, alanine and glutamic acid were very much reduced. The level of urea in the circulation dropped reversibly during protein deficiency and increased very much during total starvation.  相似文献   

7.
During long-distance exercise, branched-chain amino acid (BCAA) catabolism could lead to an increase in the blood tryptophan/BCAA ratio and an early onset of 'central fatigue'. Based on these considerations, we studied the modifications of blood serum BCAA and tryptophan (Try) levels in 30 endurance horses competing in rides varying in distance from 20 to 72 km. From all horses, blood samples were drawn just before and just after the end of the ride. Samples were analysed for their leucine (Leu), valine (Val), isoleucine (Iso) and Try levels. Data were processed by anova, using sampling moment and ride as factors, and by LSD post hoc test. Significant differences were recorded among the different distance rides for Leu, Val, Iso, Try, Try/BCAA ratio; the same trend was recorded between samples taken at the start and the end of the race for Val and Leu. The main effect observed was an increase of BCAA levels for all rides, except the 72-km ride; for Try, a significant increase was present in all races, except the 50-km ride. The Try/BCAA ratio decreased in 20- and 50-km races and increased in the others. These data confirm that long-distance exercise involves a mobilization of BCAA. The utilization of BCAA seems to be important in prolonged exercise: in the 72-km ride, we observed a decrease in BCAA blood serum levels, while a major role of Try was indicated by its increase, resulting in a rise of the Try/BCAA ratio.  相似文献   

8.
This study was conducted to test the hypothesis that porcine jejunal mucosal cells can degrade all essential amino acids (EAA). Jejunal mucosal cells (primarily enterocytes) were isolated from 50-day-old healthy pigs and incubated at 37 °C for 45 min in Krebs buffer containing plasma concentrations of amino acids and one of the following l-[1-14C]- or l-[U-14C]-amino acids plus unlabeled tracers at 0.5, 2, or 5 mM: histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine. There was active transamination of leucine, isoleucine and valine in the cells (1.35–2.5 nmol/mg protein per 45 min at 2 mM), with most (67–71%) of their -ketoacids released into the medium. In contrast, catabolism of methionine and phenylalanine was negligible (0.04–0.05 nmol/mg protein per 45 min at 2 mM) and that of other EAA was completely absent in these cells. These results indicate that intestinal mucosal cells are a site for the substantial degradation of branched-chain amino acids but not other EAA in pigs.  相似文献   

9.
Background: Alterations in circulating amino acids have been documented in animal models and in critically ill people but have not been evaluated in dogs with spontaneously occurring disease.
Hypothesis/Objectives: To compare amino acid concentrations in critically ill dogs and healthy controls and to investigate potential relationships among amino acids, markers of inflammation, illness severity, and clinical outcome.
Animals: Forty-eight critically ill dogs and 24 healthy control dogs.
Methods: Plasma was analyzed for amino acids and C-reactive protein (CRP) was measured in serum. The Fischer ratio (the molar ratio of branched chain amino acids [BCAA] to aromatic amino acids [AAA]) and survival prediction index (SPI2) were calculated.
Results: Median CRP concentrations were significantly higher in the critically ill dogs compared with controls ( P < .001). Critically ill dogs had significantly lower concentrations of alanine ( P = .001), arginine ( P < .001), citrulline ( P < .001), glycine ( P < .001), methionine ( P < .001), proline ( P < .001), and serine ( P = .001) but significantly higher concentrations of lysine ( P = .02) and phenylalanine ( P < .001; Table 1 ). This pattern resulted in a significantly lower Fischer ratio ( P = .001) in the critically ill group. Median SPI2 score was significantly higher in dogs that survived ( P = .03). Concentrations of arginine ( P = .02), isoleucine ( P = .01), leucine ( P = .04), serine ( P = .04), valine ( P = .04), total BCAA ( P = .03), and the Fischer ratio ( P = .03) were significantly higher in survivors compared with nonsurvivors.  

  Table 1.   Comparison between critically ill and healthy control dogs and among different subgroups of diseases within the critically ill group.  相似文献   


10.
The time‐dependent changes in intramuscular amino acid (AA) levels caused by exercise and by feeding a protein/AA supplement were analysed in nine horses. Horses were submitted to a total of four standardized exercise tests (SETs). Amino acid concentrations were determined prior to, immediately after, 4 and 18 h after exercise. The experiment was subdivided into two consecutive periods of 3 weeks. In each period two SETs were performed. In the second period, horses were given a protein/AA supplement within 1 h after exercise. Significant changes in mean plasma AA levels similar to previous studies were noted to be time‐dependent and to be associated with feeding the supplement. The intramuscular concentrations of the free AA in relation to pre‐exercise levels showed significant time‐dependent changes for alanine, asparagine, aspartate, citrulline, glutamine, glycine, isoleucine, leucine, methionine, serine, taurine, threonine, tyrosine and valine. Feeding the supplement significantly increased the 4 h post‐exercise intramuscular concentration of alanine, isoleucine, methionine and tyrosine. At 18 h after exercise, apart from isoleucine and methionine, levels were still increased and also those of asparagine, histidine and valine in relation to none treatment. Hence, it was concluded that AA mixtures administered orally to horses within 1 h after exercise increased intramuscular AA pool.  相似文献   

11.
1. Diets 50% deficient in single essential amino acids were fed to chicks from day 8 to day 18 after hatching to evaluate body-weight gain, food consumption, body composition, nitrogen (N) and energy utilisation. 2. Body-weight gain was reduced most severely by deficiency of isoleucine followed in decreasing order by threonine, arginine, valine, histidine, tryptophan, methionine plus cystine, phenylalanine plus tyrosine, leucine and lysine, and possible reasons for the differences are discussed. 3. Body-weight gain and food efficiency were highly correlated with food consumption but metabolisable energy value of diets was not affected by single essential amino acid deficiencies. 4. Generally N retention (N retained/N consumed) and energy retention (energy retained/energy consumed) reflected food consumption, except for a lower N retention by chicks fed on the methionine plus cystine-deficient diet and for a lower energy retention by chicks fed on the valine deficient diet. 5. The amino acid deficient in the diet was present at very low concentration in the blood plasma.  相似文献   

12.
Three sheep with a small isolated rumen (after Gridin et al., 1964) were studied for the passage of amino acids from the blood to the isolated rumen before feeding and 1, 2, 3, 4 and 5 hours after feeding. It was found that, on an average for all the time intervals mentioned above, the passage of glycine was the largest of all the amino acids studied (0.512 muMol per 100 ml), followed, in descending order, by lysine, alanine, glutamic acid, aspartic acid, serine, leucine, threonine, isoleucine, arginine, tyrosine, and phenylalanine (0.038 muMol per 100 ml). Before feeding and one hour after feeding, lysine shared the greatest proportion of all amino acids that had passed into the isolated rumen (0.565-0.43 muMol per 100 ml), followed, in descending order, by glycine, alanine, valine, aspartic acid, glutamic acid, leucine, serine, threonine, isoleucine, tyrosine, phenylalanine; arginine was, in this case, represented by the smallest proportion (0.042-0.030 muMol per 100 ml). It is inferred from the results that the amount of amino acids passing from the blood through the rumen wall changes with the time that has elapsed from feeding, and that before feeding this passage is more intensive than after feeding. These changes are held to be related with an increased passage of endogenous nitrogen to the rumen in the period of a relative deficiency of substances which are derived from the feed and are essential for maintaining homeostasis in the rumen.  相似文献   

13.
Four multiparous Holstein cows were fed a basal diet balanced with the Cornell Net Protein and Carbohydrate System (CNCPS). Diets were formulated to be co-limiting in intestinally absorbable supplies of methionine, lysine, and isoleucine. Cows were supplemented with no amino acids (control); lysine and methionine in a ruminally protected form; isoleucine by abomasal infusion; or lysine, methionine, and isoleucine in a 4x4 Latin square arrangement of treatments with 28-d periods. Performance of cows on all treatments was lower than expected due to low intake of DM that could have been caused by the high fiber level of the basal diet. This high fiber level was likely responsible for the high daily chewing times for cows fed all diets, which was consistent with the high ruminal pH values. Intake of DM and its components were not influenced by any treatment. Milk protein percentage tended to be higher when cows were fed diets supplemented with ruminally protected lysine and methionine; however, production of milk, milk fat, and milk lactose were not affected by any treatment. Cows tended to have a higher milk lactose proportion and tended to produce more milk and milk lactose when they were abomasally infused with isoleucine alone. However, when cows were supplemented with all three amino acids, milk production and composition did not differ from that of cows fed the unsupplemented diet. Use of the CNCPS to evaluate the performance of the cows fed the unsupplemented diet suggested that these cows may have been colimited by intestinally absorbable supplies of lysine, isoleucine, and methionine in addition to metabolizable protein. Evaluation of the unsupplemented diet with an alternate model, Shield, suggested that cows fed the unsupplemented diet may have been colimited by intestinally absorbable supplies of lysine, isoleucine, and arginine. Results suggest that enhanced delivery of intestinally absorbable isoleucine may stimulate milk lactose synthesis.  相似文献   

14.
Concentrations of amino acids in the plasma of 13 neonatal foals with septicemia were compared with the concentrations of amino acids in the plasma of 13 age-matched neonatal foals without septicemia. Analysis of the results revealed significantly lower concentrations of arginine, citrulline, isoleucine, proline, threonine, and valine in the plasma of foals with septicemia. The ratio of the plasma concentrations of the branched chain amino acids (isoleucine, leucine, and valine) to the aromatic amino acids (phenylalanine and tyrosine), was also significantly lower in the foals with septicemia. In addition, the concentrations of alanine, glycine, and phenylalanine were significantly higher in the plasma of foals with septicemia. Therefore, neonatal foals with septicemia had significant differences in the concentrations of several amino acids in their plasma, compared with concentrations from healthy foals. These differences were compatible with protein calorie inadequacy and may be related to an alteration in the intake, production, use, or clearance of amino acids from the plasma pool in sepsis.  相似文献   

15.
The metabolism of amino acids and urea in an isolated perfused wall of sheep rumen was studied by the method of organ perfusion, using 3 kinds of perfusate. In experiments with semisynthetic perfusate containing urea (SPurea) the levels of lysine, valine, glutamic acid and alanine increased at a simultaneous decrease of levels of leucine, arginine, aspartic acid, threonine and methionine. In perfusions with the semisynthetic medium without urea (SP) the levels of lysine, valine, phenylalanine, isoleucine, glutamic acid, glycine and alanine increased, the level of threonine dropped. In perfusions with whole autologous blood (KP) the levels of valine, glutamic acid and alanine increased, the level of arginine decreased. The level of urea decreased sharply at using SPurea and KP, however, the equal cumulation of ammonia (200-400 mumol x 1(-1)) was found in all three types of perfusate after 2-hr perfusion. Moreover, in experiments with SP a low level of urea was found already after 5-min. of perfusion. The results of the experiments suggest that the rumen wall is capable of producing amino acids also without the contents of rumen, and that independently on the presence or absence of urea as a nitrogen source.  相似文献   

16.
The multiplication rates of 70 porcine Escherichia coli strains were compared in minimal medium and in medium supplemented with aspartic acid, lysine, serine and threonine, which were the amino acids taken up during multiplication of porcine E. coli in a complex medium. The effects of these amino acids singly or in combinations and the amino acids norleucine and norvaline on the growth of porcine E. coli were studied. Together, aspartic acid, threonine, serine and lysine increased the multiplication rates of 42.9% of the strains, an effect traced to aspartic acid, but they had no effect on an equal number of strains. The rest were inhibited, and this effect was traced to serine. Cysteine, threonine, leucine and phenylalanine singly inhibited some or all of the strains tested. Norleucine and to a lesser extent, norvaline greatly prolonged the lag phase of culture in minimal medium. The inhibitory effect of norleucine was reversed by only methionine, although isoleucine, leucine and valine which were more effective in norvaline inhibition, also showed limited antagonism to norleucine inhibition.  相似文献   

17.
为评估9~12周龄皖西白鹅氨基酸需要量，本研究基于析因法原理选取9周龄皖西白鹅84只和成年健康公鹅16只，通过生长鹅屠宰试验和成年鹅氮平衡试验测定9和12周龄皖西白鹅胴体和羽毛氨基酸含量与成年公鹅排泄物氨基酸和肌酐含量。结果表明：9周龄皖西白鹅胴体和羽毛氨基酸组成（模式）与12周龄相比无显著差异（P>0.05）；9~12周龄皖西白鹅生长氨基酸需要量（模式）为：赖氨酸（Lys）1 803.16 mg/d（100）、蛋氨酸（Met）464.85 mg/d（26）、胱氨酸（Cys）775.56 mg/d（69）、苏氨酸（Thr）1 032.40 mg/d（57）、组氨酸（His）482.37 mg/d（27）、缬氨酸（Val）1 200.68 mg/d（67）、亮氨酸（Leu）1 862.72 mg/d（103）、异亮氨酸（Ile）1 043.63 mg/d（58）、精氨酸（Arg）1 203.58 mg/d（67）、苯丙氨酸（Phe）660.97 mg/d（37）、丝氨酸（Ser）1 322.75 mg/d（73）、脯氨酸（Pro）824.05 mg/d（46）；维持氨基酸需要量（模式）为：Lys 172.29 mg/d（100）、Met 161.14 mg/d（94）、Cys 633.05 mg/d（367）、Thr 398.08 mg/d（231）、His 70.52 mg/d（41）、Val 548.26 mg/d（318）、Leu 626.06 mg/d（363）、Ile 362.46 mg/d（210）、Arg 506.62 mg/d（294）、Phe 299.31 mg/d（174）、Ser 882.53 mg/d（477）、Pro 693.37 mg/d（402）；9~12周龄皖西白鹅饲粮氨基酸水平为：Lys 0.77%、Met 0.24%、Cys 0.55%、Thr 0.56%、His 0.21%、Val 0.68%、Leu 0.97%、Ile 0.55%、Arg 0.66%、Phe 0.37%、Ser 0.83%、Pro 0.59%。  相似文献   

18.
为评估9~12周龄皖西白鹅氨基酸需要量,本研究基于析因法原理选取9周龄皖西白鹅84只和成年健康公鹅16只,通过生长鹅屠宰试验和成年鹅氮平衡试验测定9和12周龄皖西白鹅胴体和羽毛氨基酸含量与成年公鹅排泄物氨基酸和肌酐含量。结果表明:9周龄皖西白鹅胴体和羽毛氨基酸组成(模式)与12周龄相比无显著差异(P>0.05);9~12周龄皖西白鹅生长氨基酸需要量(模式)为:赖氨酸(Lys)1803.16 mg/d(100)、蛋氨酸(Met)464.85 mg/d(26)、胱氨酸(Cys)775.56 mg/d(69)、苏氨酸(Thr)1032.40 mg/d(57)、组氨酸(His)482.37 mg/d(27)、缬氨酸(Val)1200.68 mg/d(67)、亮氨酸(Leu)1862.72 mg/d(103)、异亮氨酸(Ile)1043.63 mg/d(58)、精氨酸(Arg)1203.58 mg/d(67)、苯丙氨酸(Phe)660.97 mg/d(37)、丝氨酸(Ser)1322.75 mg/d(73)、脯氨酸(Pro)824.05 mg/d(46);维持氨基酸需要量(模式)为:Lys 172.29 mg/d(100)、Met 161.14 mg/d(94)、Cys 633.05 mg/d(367)、Thr 398.08 mg/d(231)、His 70.52 mg/d(41)、Val 548.26 mg/d(318)、Leu 626.06 mg/d(363)、Ile 362.46 mg/d(210)、Arg 506.62 mg/d(294)、Phe 299.31 mg/d(174)、Ser 882.53 mg/d(477)、Pro 693.37 mg/d(402);9~12周龄皖西白鹅饲粮氨基酸水平为:Lys 0.77%、Met 0.24%、Cys 0.55%、Thr 0.56%、His 0.21%、Val 0.68%、Leu 0.97%、Ile 0.55%、Arg 0.66%、Phe 0.37%、Ser 0.83%、Pro 0.59%。  相似文献   

19.
大肠杆菌新菌毛抗原的研究Ⅱ．菌毛抗原蛋白质特性测定   总被引：2，自引：0，他引：2  
用保温法和裂解法可以有效提取Ｆ_(１９８７)新菌毛抗原蛋白质；该菌毛蛋白经区带电泳显示主、次两个组分，在０．０６ｍｏｌ／ＬｐＨ８．６巴比妥缓冲液电泳条件下，均向阳极泳动；免疫电泳显示两条沉淀线；其分子量为１９１００Ｄａ；等电点为３．０；由天门冬氨酸、苏氨酸、丝氨酸、谷氨酸、甘氨酸、丙氨酸、缬氨酸、异亮氨酸、亮氨酸、酪氨酸、苯丙氨酸、赖氨酸、组氨酸、精氨酸、脯氨酸、胱氨酸等１６种氨基酸组成。  相似文献   

20.
The objective of this study is to assess the influence of acute exercise, training and intensified training on the plasma amino acid profile.In a 32-week longitudinal study using 10 Standardbred horses, training was divided into four phases, including a phase of intensified training for five horses. At the end of each phase, a standardized exercise test, SET, was performed. Plasma amino acid concentrations before and after each SET were measured.Training significantly reduced mean plasma aspartic acid concentration, whereas exercise significantly increased the plasma concentrations of alanine, taurine, methionine, leucine, tyrosine and phenylalanine and reduced the plasma concentrations of glycine, ornithine, glutamine, citrulline and serine. Normally and intensified trained horses differed not significantly. It is concluded that amino acids should not be regarded as limiting training performance in Standardbreds except for aspartic acid which is the most likely candidate for supplementation.  相似文献   

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