Effects of submaximal exercise on adenine nucleotide concentrations in skeletal muscle fibers of horses with polysaccharide storage myopathy

OBJECTIVE: To determine whether disruption of adenine triphosphate (ATP) regeneration and subsequent adenine nucleotide degradation are potential mechanisms for rhabdomyolysis in horses with polysaccharide storage myopathy (PSSM) performing submaximal exercise. ANIMALS: 7 horses with PSSM and 4 control horses. PROCEDURES: Horses with PSSM performed 2-minute intervals of a walk and trot exercise on a treadmill until muscle cramping developed. Control horses exercised similarly for 20 minutes. Serum creatine kinase (CK) activity was measured 4 hours after exercise. Citrate synthase (CS), 3-OH-acylCoA dehydrogenase, and lactate dehydrogenase activities prior to exercise and glucose-6-phosphate (G-6-P) and lactate concentrations before and after exercise were measured in gluteal muscle specimens. Adenine triphosphate, diphosphate (ADP), monophosphate (AMP), and inosine monophosphate (IMP) concentrations were measured before and after exercise in whole muscle, single muscle fibers, and pooled single muscle fibers. RESULTS: Serum CK activity ranged from 255 to 22,265 U/L in horses with PSSM and 133 to 278 U/L in control horses. Muscle CS activity was lower in horses with PSSM, compared with control horses. Muscle G-6-P lactate, ATP, ADP, and AMP concentrations in whole muscle did not change with exercise in any horses. Concentration of IMP increased with exercise in whole muscle, pooled muscle fibers, and single muscle fibers in horses with PSSM. Large variations in ATP and IMP concentrations were observed within single muscle fibers. CONCLUSIONS AND CLINICAL RELEVANCE: Increased IMP concentration without depletion of ATP in individual muscle fibers of horses with PSSM during submaximal exercise indicates an energy imbalance that may contribute to the development of exercise intolerance and rhabdomyolysis.     

复方丁氨丙磷溶液对小白鼠耐力和能量代谢的影响

为探讨复方丁氨丙磷溶液对动物耐力和能量代谢的影响。采用小白鼠耐寒、耐热、耐缺氧和负荷游泳试验以及用经典蒽酮显色法和反相高效液相色谱法分别测定肝脏和骨骼肌中的糖原含量和3种磷酸腺苷含量，观察复方丁氨丙磷溶液对小白鼠耐力和能量代谢的影响。结果表明：复方丁氨丙磷溶液能明显提高小白鼠耐寒、耐热和耐缺氧能力。明显延长小白鼠负荷游泳时间；能显著提高肝糖原和肌糖原含量以及肝组织和肌肉组织的三磷酸腺苷(ATP)、二磷酸腺苷(ADP)含量。而对肝组织一磷酸腺苷(AMP)含量无明显影响，对肌肉组织一磷酸腺苷含量却有一定的降低作用。说明复方丁氨丙磷溶液是通过提高肝糖原和肌糖原储备以及促进ATP和ADP的合成代谢来增强动物的耐力和能量代谢。     

Dietary α‐ketoglutarate supplementation improves hepatic and intestinal energy status and anti‐oxidative capacity of Cherry Valley ducks

α‐Ketoglutarate (AKG) is an extensively used dietary supplement in human and animal nutrition. The aim of the present study was to investigate effects of dietary AKG supplementation on the energy status and anti‐oxidative capacity in liver and intestinal mucosa of Cherry Valley ducks. A total of 80 1‐day‐old ducks were randomly assigned into four groups, in which ducks were fed basal diets supplemented with 0% (control), 0.5%, 1.0% and 1.5% AKG, respectively. Graded doses of AKG supplementation linearly decreased the ratio of adenosine monophosphate (AMP) to adenosine triphosphate (ATP) in the liver, but increased ATP content and adenylate energy charge (AEC) in a quadratic and linear manner, respectively (P < 0.05). Increasing dietary AKG supplemental levels produced linear positive responses in ATP content and AEC, and negative responses in AMP concentration, the ratio of AMP to ATP and total adenine nucleotide in the ileal mucosa (P < 0.05). All levels of dietary AKG reduced the production of jejunal hydrogen peroxide and hepatic malondialdehyde (P < 0.05). Hepatic and ileal messenger RNA expression of AMP kinase α‐1 and hypoxia‐inducible factor‐1α were linearly up‐regulated as dietary AKG supplemental levels increased (P < 0.05). In conclusion, dietary AKG supplementation linearly or quadratically enhanced hepatic and intestinal energy storage and anti‐oxidative capacity of Cherry Valley ducks.     

The Effects of Ischemia and Reperfusion on Mucosal Respiratory Function, Adenosine Triphosphate, Electrolyte, and Water Content in the Ascending Colon of Ponies

Objective- The purpose of this study was to examine the effects of ischemia and reperfusion on the biochemical integrity of equine colonic mucosa to assess the relative roles of ischemic- and reperfusion-induced damage.
Study Design- Two hours of no-flow ischemia experimentally induced by 720° counterclockwise ascending colon volvulus followed by 2 hours reperfusion after derotation.
Animals- Ten ponies.
Methods- Ascending colon biopsies were obtained every hour for measurement of mucosal adenosine triphosphate (ATP), water, sodium, and potassium content. Additional samples were homogenized for assay of mitochondrial respiratory function.
Results- ATP content diminished 92% after ischemia and recovered to only 44% of control levels ( P <.001 versus controls) after 2 hours reperfusion. Reperfusion increased mucosal water and decreased sodium and potassium content for the duration of the experiment. Both NADH- (pyruvate) and FADH-linked (succinate) respiration decreased after ischemia and did not recover during reperfusion indicating electron transport chain dysfunction.
Conclusions- Two hours ischemia induced severe metabolic dysfunction in equine colon mucosa which persisted throughout reperfusion. Unequivocal evidence of injury specific to reperfusion was not observed in this study suggesting that much of the damage observed during reperfusion may be a continuation of injury induced during the ischemic period and not specific to reperfusion per se.
Clinical Relevance- This study suggests that greater efforts to metabolically support ischemically injured mucosa may be an important aspect of obtaining improved survival of horses affected by ascending colon volvulus (ACV).     

Loss of absorptive capacity for sodium and chloride in the colon causes diarrhoea in Potomac horse fever

Ehrlichia risticii, an obligate intracellular bacterium in the family Rickettsiaceae, causes Potomac horse fever which is often associated with severe watery diarrhoea. The mechanism of the diarrhoea is unknown. The aim of this study was to determine whether sodium and chloride transport, morphology and cyclic adenosine 3', 5'-monophosphate (cyclic AMP) content of colonic mucosa was altered in E risticii-infected horses. Mucosa-submucosa sheets from the large and small colon of nine infected and seven to nine uninfected horses were set up in Ussing chambers for measurement of short-circuit current and transepithelial 22Na and 36Cl fluxes. Uninfected tissues absorbed both sodium and chloride whereas absorption of sodium and chloride was abolished in infected tissues. Bethanechol and histamine evoked a concentration-dependent increase in short-circuit current in both groups, but the responses were attenuated at all concentrations in infected horses. Slight focal degeneration of colonic epithelial cells and loss of microvilli from glandular epithelial cells occurred in infected horses. There was a significant increase in cyclic AMP content in colonic mucosa of infected animals. The results suggest that E risticii infection induces focal microscopic degeneration of epithelial cells and an increase in intracellular cyclic AMP in colonic mucosa. These alterations are associated with malabsorption of sodium and chloride and could cause diarrhoea.     

中草药添加剂对绵羊肌肉组织中鲜味物质含量的影响

试验旨在研究自拟中草药添加剂对绵羊肌肉组织中鲜味物质含量的影响。选用32只10月龄绵羊,随机分为4组,即试验1、2、3和4组。试验1组为对照组,饲喂基础日粮;试验2、3和4组在基础日粮中分别添加1%方剂Ⅰ、1%方剂Ⅱ和1%方剂Ⅲ,进行为期60 d的饲养试验,采用反相高效液相色谱（RP-HPLC）法检测肉样中肌苷酸（IMP）及其相关代谢物的含量。结果表明,所有试验样品中均不含三磷酸腺苷（ATP）成分,二磷酸腺苷（ADP）、次黄嘌呤（HYP）和一磷酸腺苷（AMP）的含量亦很低,且各组数据间均无显著差异（P>0.05）;3个中草药添加剂组均能不同程度的提高绵羊肉中IMP及其分解产物的含量,其中试验4组IMP、肌苷（INO）和校正肌苷酸（IMPc）值均极显著高于试验1组（P<0.01）,与试验2、3组相比亦存在显著差异（P<0.05）。提示,方剂Ⅲ能显著改善绵羊肉的风味。     

Effect of creatine supplementation on muscle metabolic response to a maximal treadmill exercise test in Standardbred horses

The aim of the present study was to investigate the effect of creatine (Cr) supplementation on muscle metabolic response in connection with a maximal treadmill exercise test, known to cause a marked anaerobic metabolic response and adenine nucleotide degradation. First, 6 Standardbred trotters performed a standardised maximal exercise test until fatigue (baseline test). The test used was an inclined incremental treadmill test in which the speed was increased by 1 m/s, starting at 7 m/s, every 60 s until the horse could no longer keep pace with the treadmill. After this baseline test, the horses were separated into 2 equal groups. One half received a dose of 25 g creatine monohydrate twice daily, and the other group were given the same dose of lactose (placebo). The supplementation period was 6.5 days, after which the maximal treadmill exercise test was performed again. A washout period of 14 days was allowed before treatments were switched between groups and a new supplementation period started. After this second supplementation period a new maximal exercise test was performed. After supplementation with creatine or placebo, horses were stopped after performing the same number of speed steps and duration of exercise as they had in the baseline test. Blood samples for analysis of plasma lactate, creatine (Cr), creatinine, hypoxanthine, xanthine and uric acid concentrations were collected at rest, during each speed step and during recovery. The total blood volume (TBV) was also determined. Muscle biopsies for analysis of muscle metabolites (adenosine triphosphate [ATP], adenosine diphosphate [ADP], adenosine monophosphate [AMP], inosine monophosphate [IMP], creatine phosphate [CP], lactate [La] and glycogen) were taken at rest, immediately post exercise and after 15 min recovery. The results showed no significant increase in plasma Cr or muscle total creatine concentration (TCr) after supplementation with Cr. At the end of exercise ATP and CP concentrations had decreased and IMP and lactate concentrations increased in muscle in all groups. Plasma lactate concentration increased during exercise and recovery and plasma uric acid concentration increased during recovery in all groups. No influence could be found in TBV after supplementation with creatine. These results show that creatine supplementation in the dosage used in this study had no influence on muscle metabolic response or TBV.     

Detection and comparison of nitric oxide in clinically healthy horses and those with naturally acquired strangulating large colon volvulus

The objective of the study was to determine whether nitric oxide (NO) is present in clinically healthy horses (control) under basal conditions, and if it increases secondary to naturally acquired strangulating large colon volvulus (affected). Eleven affected horses and 10 controls were studied. Jugular venous blood, abdominal fluid, and urine were collected. The NO concentrations were standardized to the creatinine concentration in the respective samples. A biopsy specimen collected from the large colon pelvic flexure at surgery was divided into subsections for processing for inducible nitric synthase (iNOS) and nitrotyrosine (NT) immunohistochemical staining and reduced nicotinamide adenine dinucleotide phosphate (NADPH) diaphorase histochemical staining. There were no significant differences in plasma, abdominal fluid, or urine NO concentrations between affected and control horses. There was a significant decrease in submucosal arteriolar and venular endothelium, submucosal plexus, mucosal leukocyte, mucosal and musclaris vasculature, and myenteric plexus NADPH diaphorase staining in affected versus control horses. There was a significant increase in iNOS staining in mucosal leukocytes and vasculature in affected versus control horses. Other than a greater number of positively stained mucosal leukocytes in affected horses, there were no significant differences between affected and control horses for NT staining. The presence of NADPH diaphorase staining in the endothelium and submucosal neurons suggests endothelial and neuronal NOS are present under basal conditions in the large colon of horses. Increased iNOS and NT staining in mucosal leukocytes of affected horses suggests involvement of the NO pathway in large colon volvulus. The reasons for the lack of a significant difference in plasma, abdominal fluid, and urine NO concentrations between affected and control horses are unknown.     

Effect of dietary protein on porcine colonic microstructure and function

Twelve feeder pigs were used to determine the effects of dietary protein on colonic microstructure and function. Scanning electron microscopy indicated marked differences in mucosal structure of pigs fed 12% vs 20% crude protein. Quantitative assessment of the morphologic features of the colon, using light microscopy, indicated significant differences in the mucosa of pigs fed 12% vs 20% crude protein and significant differences between the proximal and distal portions of the colon. Morphologic changes were associated with differences in the colonic transport of fluids and electrolytes. Dietary protein principally affected the transport of sodium, bicarbonate, and acetate. The transport of total volatile fatty acids and acetate flux were significantly different between the proximal and distal portions of the colon.     

N-乙酰半胱氨酸对脂多糖刺激仔猪免疫反应和小肠能量状态的影响

试验旨在研究N-乙酰半胱氨酸（NAC）对脂多糖（LPS）刺激的仔猪免疫反应和小肠能量状态的影响。按照随机性原则将24头32日龄健康仔猪（11.58 kg±0.26 kg）分为3组（空白组、LPS组和NAC＋LPS组），每组设置8个重复。经过3 d适应期后，各组仔猪饲喂玉米-豆粕型基础饲粮（NAC＋LPS组在此基础上添加500 mg/kg NAC）。试验第21天，仔猪空腹称重后腹腔注射LPS （LPS组和NAC＋LPS组，注射剂量为100 μg/kg BW）或等量的生理盐水（空白组），3 h后前腔静脉采血，然后屠宰取肠黏膜、肝脏和淋巴结等样品，进行血细胞计数分析、小肠黏膜腺苷酸水平测定以及肝脏和淋巴结相关基因检测。结果表明，与空白组相比，LPS组仔猪血液中白细胞和中性粒细胞的数目显著提高（P<0.05），淋巴细胞数目显著降低（P<0.05）；小肠黏膜一磷酸腺苷（AMP）水平和一磷酸腺苷/三磷酸腺苷（AMP/ATP）值显著提高（P<0.05），ATP水平显著降低（P<0.05）；肝脏和淋巴结双链RNA依赖的蛋白质激酶（PKR）、干扰素诱导的四肽重复蛋白1（IFIT1）和黏病毒抗性蛋白1（MX1）基因的相对表达量均显著上调（P<0.05）。与LPS组相比，NAC＋LPS组仔猪血液中白细胞数、中性粒细胞数、嗜酸性粒细胞和淋巴细胞百分比均显著降低（P<0.05）；回肠黏膜AMP水平和AMP/ATP值均显著降低（P<0.05）；肝脏IFIT1、PKR和MX1基因的相对表达量均显著上调（P<0.05），淋巴结IFIT1基因的相对表达量显著下调（P<0.05）。综上所述，饲粮中添加500 mg/kg NAC可缓解LPS刺激引起的仔猪免疫反应，并且能有效改善肠黏膜能量状态。     

谷氨酸对脂多糖刺激断奶仔猪肠道能量代谢的影响

本试验旨在研究谷氨酸(Glu)对脂多糖(LPS)刺激断奶仔猪肠道能量代谢的影响。选择24头断奶仔猪分为4个组,分别为对照组、LPS组、LPS+1.0%Glu组和LPS+2.0%Glu组,每组6个重复,每个重复1头猪。于试验第28天,试验组猪注射100μg/kg BW LPS,对照组注射等量的生理盐水,4 h后屠宰,取肠道样品待测。结果表明:1)与对照组相比,LPS刺激导致断奶仔猪空肠三磷酸腺苷(ATP)、腺苷酸池(TAN)含量和能荷(EC)显著降低(P0.05),一磷酸腺苷(AMP)/ATP值显著升高(P0.05);与LPS组相比,LPS+2.0%Glu组显著提高了空肠ATP、二磷酸腺苷(ADP)和TAN含量(P0.05)。2)与对照组相比,LPS刺激导致断奶仔猪回肠柠檬酸合成酶和α-酮戊二酸脱氢酶系活性极显著降低(P0.01),空肠α-酮戊二酸脱氢酶系活性有降低趋势(P=0.092);与LPS组相比,除LPS+1.0%Glu组回肠柠檬酸合成酶活性显著降低(P0.05)外,Glu对空肠和回肠三羧酸循环关键酶活性无显著影响(P0.05)。3)与对照组相比,LPS刺激导致空肠过氧化物酶体增殖物激活受体γ辅激活因子1α(PGC1α)及回肠沉默信号调控因子1(Sirt1)和PGC1α的mRNA表达量极显著降低(P0.01);与LPS组相比,LPS+2.0%Glu组有提高空肠PGC1α(P=0.067)和回肠Sirt1(P=0.053)mRNA表达量的趋势,LPS+1.0%Glu组有提高回肠Sirt1 mRNA表达量的趋势(P=0.070)。由此可见,Glu可以改善LPS刺激导致的肠道能量损耗状态。     

扬州鹅及其杂交配套组合肉用仔鹅肌肉中氨基酸和肌苷酸含量的比较

为了比较扬州鹅及其杂交组合肉用仔鹅肌肉中氨基酸和肌苷酸（IMP）含量,试验以扬州鹅（A×A、B×B）及其4个杂交配套组合（B♂×A♀、K♂×A♀、D♂×A♀和C♂×A♀）共6个群体的肉用仔鹅分别作为对照组和试验组,采用氨基酸自动分析仪、高效液相色谱仪测定肌肉中氨基酸和IMP的含量。结果表明,公鹅胸肌中,除谷氨酸（Glu）、丙氨酸（Ala）、总氨基酸（TAA）、必需氨基酸（EAA）、鲜味氨基酸（DFAA）外,其他氨基酸含量在各组间均存在显著或极显著差异（P<0.05;P<0.01）;各试验组一磷酸腺苷（AMP）、IMP含量均显著高于对照组A×A （P<0.05）。公鹅腿肌中各组间天冬氨酸（Asp）、Glu含量存在显著或极显著差异（P<0.05;P<0.01）;试验组C×A、K×A肌苷（INO）含量均显著高于两对照组（P<0.05）。母鹅胸肌中各组间甘氨酸（Gly）、甲硫氨酸（Met）、精氨酸（Arg）含量存在显著或极显著差异（P<0.05;P<0.01）;试验组K×A IMP含量显著高于两对照组（P<0.05）。母鹅腿肌中各组间Asp、Glu、Met、Arg含量均存在显著或极显著差异（P<0.05;P<0.01）;试验组K×A IMP、IMPc含量均显著高于对照组A×A （P<0.05）。公、母鹅胸肌中次黄嘌呤（HYP）含量试验组C×A显著高于对照组A×A （P<0.05）,试验组B×A AMP含量显著高于两对照组 （P<0.05）。公、母平均腿肌中各组间Ala含量存在显著差异（P<0.05）;试验组K×A、D×A AMP含量均显著高于两对照组（P<0.05）。由此可见,扬州鹅杂交配套组合在一定程度上提高了肌肉中氨基酸和肌苷酸含量,改善了肉品质。     

Changes in purine levels associated with cellular brain injury in gerbils experimentally infected with Neospora caninum

The present study was carried out in order to assess the possible alterations in purine levels of brain, associated neuronal lesions in gerbils experimentally infected with Neospora caninum. For that, gerbils (Meriones unguiculatus) were inoculated with Nc-1 strain of N. caninum, composing two different experiments: Experiment I (EI) and experiment II (EII), where purine levels were measured along with the histopathologic study, on days 7 (EI), 15 and 30 (EII), post-infection (PI). As a result, it was possible to observe that the purine levels (ATP, ADP, AMP, adenosine, inosine and xanthine) in brain in EI are significantly reduced (p < 0.05), while in EII we faced a different pattern, since in the majority the purine levels were significantly increased (p < 0.05) on days 15 (ATP, AMP, adenosine, hypoxanthine and xanthine) and 30 PI (ATP, ADP, AMP, adenosine, and uric acid). Results of brain histopathology did not show histological lesion in animals of EI; however, in gerbils of EII it was possible to verify that the alterations (lesions) were more pronounced in gerbils evaluated on day 30 PI when compared to day 15 PI. Therefore, it was possible to conclude that the purine levels in brain were altered in both experiments, concomitant with the histopathological injuries observed in EII.     

The effect of cholera toxin and heat labile and heat stable Escherichia coli enterotoxin on cyclic AMP concentrations in small intestinal mucosa of pig and rabbit.

The effect of cholera toxin, heat labile and heat stable Escherichia coli enterotoxin on mucosal cyclic AMP concentrations was determined on the proximal jejunum of weanling pigs and young rabbits. Ligated loops were injected with solutions containing no enterotoxin for control and either cholera toxin, heat labile or heat stable E. coli enterotoxin. The loops were drained after either two, four or six hours incubation at which time accumulated fluid was recorded and mucosal samples removed for determination of cyclic AMP concentration. In the rabbit, cholera toxin and heat labile, but not heat stable E. coli enterotoxin stimulated intestinal secretion while in the pig all three enterotoxins induced net fluid accumulation. Cholera toxin and heat labile, but not heat stable E. coli enterotoxin elevated rabbit mucosal cyclic AMP concentrations. In the pig these enterotoxins had no significant effect on mucosal cyclic AMP concentrations. The results are inconsistent with the hypothesis that the adenyl cyclase system is an essential step for enterotoxin induced intestinal secretion. The activation of intestinal adenyl cyclase by bacterial enterotoxins may only be an associated and not a necessary event for the stimulation of intestinal secretion.     

发酵液中维生素B12检测方法的比较

为建立准确检测发酵液中微量维生素B12的检测方法,采用对照薄层层析法（TLC）、高效液相色谱法（HPLC）以及色谱一质谱联用（LC—MS）检测发酵液中维生素B12的含量。结果表明,TLC和HPLC在检测发酵液中维生素B12时结果误差较大,LC—MS能够精确检测出发酵液中存在的微量的维生素B12。     

Effects of acetylcysteine and migration of resident eosinophils in an in vitro model of mucosal injury and restitution in equine right dorsal colon

OBJECTIVES: To evaluate the in vitro protective effects of acetylcysteine and response of resident mucosal eosinophils in oxidant-induced injury to tissues of right dorsal colon of horses. ANIMALS: 9 adult horses. PROCEDURE: Gastrointestinal mucosa was damaged in vitro with 3 mM hypochlorous acid (HOCl), with and without prior exposure to 6mM acetylcysteine. Control tissues were not exposed to HOCl or acetylcysteine. Control and damaged tissues were incubated in Krebs-Ringer-bicarbonate solution and tissue resistance measured during 240 minutes. Tissue permeability to radiolabeled mannitol was also used to assess mucosal barrier integrity. Tissues were examined by light microscopy before and after HOCl exposure and during and after incubation. RESULTS: Exposure to HOCl caused tissue damage and decreased tissue resistance. Restitution did occur during the incubation period. Eosinophils were located near the muscularis mucosae in freshly harvested tissues and migrated towards the luminal surface in response to HOCl-induced injury. Compared with tissues treated with HOCl without acetylcysteine, pretreatment with acetylcysteine prevented HOCl-induced tissue damage, changes in resistance, and histologically detectable eosinophil migration. The permeability to mannitol increased to the same extent in tissues treated with HOCl alone or with acetylcysteine and HOCl. CONCLUSIONS AND CLINICAL RELEVANCE: Eosinophils migrated toward the mucosal surface in equine colon in response to oxidant-induced damage in vitro. This novel finding could be relevant to inflammation in equine colon and a pathophysiologic feature of many colonic diseases. Acetylcysteine protected the mucosa against oxidant-induced injury and may be useful as a treatment option for various gastrointestinal tract disorders in horses.     

市售进口Camembert干酪的蛋白质水解程度和生物胺水平对比研究

比较分析6 种不同品牌的市售进口Camembert干酪的蛋白质水解程度和生物胺水平差异。分别测定不同干酪样品的水分含量、pH值和游离氨基酸含量等指标,采用凯式定氮仪和高效液相色谱仪测定干酪的蛋白质水解程度和生物胺含量。结果表明:不同品牌Camembert干酪的pH值、蛋白质水解指标和游离氨基酸含量存在显著性差异(P<0.05),且不同品牌Camembert干酪的成熟度不同,干酪的pH值与蛋白质水解指标呈正相关;不同品牌Camembert干酪的生物胺含量存在显著性差异(P<0.05),但生物胺总量均在推荐限量范围内;样品FRA1的蛋白质水解程度最高,成熟度最高。     

硫胺素在鸡肌肉中的沉积规律研究

为研究鸡肌肉组织中硫胺素的沉积规律,以如皋鸡和文昌鸡为素材,分不同家系、周龄、组织进行取样,采用高效液相色谱法检测样品中的硫胺素含量。结果显示,不同品种、家系、周龄及组织间硫胺素含量均存在显著或极显著差异（P<0.05或P<0.01）。此外,硫胺素含量的遗传力为0.494,与体重的遗传相关为-0.404。以上结果初步表明,硫胺素在机体的沉积受遗传因素影响,且表现为一定的时间和组织变化规律,可以通过选择进行提高。     

The effect of experimental gastric dilatation-volvulus on adenosine triphosphate content and conductance of the canine gastric and jejunal mucosa

The objective of this study was to determine if experimental gastric dilatation volvulus (GDV) would decrease adenosine triphosphate (ATP) concentration and increase membrane conductance of the canine gastric and jejunal mucosa. Male dogs (n = 15) weighing between 20 and 30 kg were used. Dogs were randomly assigned to 1 of 3 equal groups: Group 1 was control, group 2 was GDV, and group 3 was ischemia. All dogs were anesthetized for 210 min. Group 1 had no manipulation. Group 2 had GDV experimentally induced for 120 min followed by decompression, derotation, and reperfusion for 90 min. Group 3 had GDV experimentally induced for 210 min. Gastric (fundus and pylorus) and jejunal tissue was taken at 0, 120, and 210 min from all of the dogs. Tissue was analyzed for ATP concentration, mucosal conductance, and microscopic changes. The ATP concentration in the fundus did not change significantly from baseline in group 2, but decreased significantly below baseline at 210 min in group 3. The ATP concentration in the jejunum decreased significantly below baseline in groups 2 and 3 at 120 min, remaining significantly decreased in group 3 but returning to baseline at 210 min in group 2. Mucosal conductance of the fundus did not change significantly in any dog. Mucosal conductance of the jejunum increased at 120 min in groups 2 and 3, and became significantly increased above baseline at 210 min. The jejunal mucosa showed more profound cellular changes than the gastric mucosa. The jejunum showed substantial decreases in ATP concentration with an increase in mucosal conductance, suggesting cell membrane dysfunction. Dogs sustaining a GDV are likely to have a change in the activity of mucosal cells in the jejunum, which may be important in the pathophysiology of GDV.