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1.
试验旨在探讨盐地碱蓬甜菜红素改善疲劳状态下肌力减退的作用。采用脉冲式电流直接刺激腓肠肌作为疲劳模型,对比盐地碱蓬甜菜红素和任氏液分别对蟾蜍腓肠肌疲劳的影响。结果表明,盐地碱蓬甜菜红素在浓度为0.005、0.01、0.02 mg/mL时,离体腓肠肌达到最大收缩幅度90%、50%和10%的时间显著长于在任氏液作用下的离体腓肠肌(P<0.05);0.02 mg/mL的盐地碱蓬甜菜红素也极显著的延长了在体腓肠肌达到最大收缩幅度90%、50%和10%的时间(P<0.01)。因此,盐地碱蓬甜菜红素具有延缓肌肉疲劳的作用。  相似文献   

2.
采用LMS-2B型二道生理纪录仪,分别记录分析浸于不同温度(20℃、25℃、30℃)任氏液中的牛蛙腓肠肌接受连续电刺激时的单收缩曲线。观察不同温度对接受连续刺激的腓肠肌收缩能力的影响。温度为20℃、25℃、30℃时对牛蛙腓肠肌最大收缩力的影响差异不显著(P>0.05),而对疲劳时间T0.5的影响差异显著(P<0.05)。温度在20~30℃之间变化时,对腓肠肌收缩性能的影响主要是影响其疲劳时间T0.5。  相似文献   

3.
为探讨鹿血对牛蛙离体心脏收缩力和心率的影响,采用斯氏法离体蛙心,分别用不同的鹿血对离体心脏进行灌流,用BL 420E生物技能试验系统记录离体心脏给药前、后心肌收缩力和心率的变化。试验结果表明:梅花鹿外周血、梅花鹿茸血、驯鹿外周血和驯鹿茸血与任氏液对照组相比心肌收缩力增加42.27%126.62%,差异极显著(P<0.01),其中梅花鹿外周血和驯鹿外周血较比梅花鹿茸血和驯鹿茸血对增强离体蛙心心肌收缩力更为明显,但对各组间的心率没有影响(P>0.05)。  相似文献   

4.
笔者以蛙为试验对象,研究乙醇对离体蛙心收缩程度的影响。制备离体蛙心标本,分别用3种浓度乙醇溶液(10%、20%和40%)作用于离体蛙心,利用生物信号采集处理系统采集收缩曲线,比较不同浓度乙醇溶液对离体蛙心收缩活动的影响。结果 3种浓度乙醇溶液均可抑制蛙心收缩幅度和收缩频率,且中、高剂量组差异极显著(P0.01)。说明乙醇能降低离体蛙心的收缩幅度,减小收缩频率,抑制程度与乙醇浓度呈正相关关系。  相似文献   

5.
为了揭示雌激素(estrogen,E2)对奶牛输卵管上皮细胞中前列腺素E2合成酶(PGES)和前列腺素F合成酶(PGFS)mRNA表达的影响,探讨E2对奶牛输卵管生殖生理的调节作用,本试验采用了体外培养荷斯坦奶牛输卵管上皮细胞技术,分不同时间(0、2、4、8、16、24和48 h)和不同浓度(10-12、10-11、10-10、10-9 mol/L)添加雌激素E2(以不加雌激素作空白对照),采用荧光定量PCR 技术检测PGES和PGFS mRNA表达。不同浓度的E2或同一浓度不同刺激时间的E2均能增加PGES的表达,但4 h浓度为10-10 mol/L时与空白对照相比差异极显著(P<0.01),而PGFS在24 h添加浓度为10-12 mol/L E2时与空白对照相比差异极显著(P<0.01)。试验结果表明,E2对培养的奶牛输卵管上皮细胞PGES和PGFS mRNA的表达有促进作用,说明雌激素E2对前列腺素酶PGES和PGFS mRNA的表达具有调控作用。  相似文献   

6.
 对商品肉鸡舍内主要环境因子如氧气、二氧化碳、氨气、硫化氢浓度、细菌浓度以及温度、湿度等进行定量检测,并分析各环境因子变化规律。试验结果显示,该鸡舍内氧气浓度平均为19.6%,比舍外降低6.0%;二氧化碳浓度平均为3 673×106 mg/m3,为舍外二氧化碳浓度的8.48倍;细菌浓度平均为6.9×105 cfu/m3;舍内平均温度为24.0 ℃,相对湿度为75.5%;氨气浓度在试验期间均超过100 mg/m3;硫化氢浓度低于检测仪器最低浓度1 mg/m3。试验表明,鸡舍内空气环境中二氧化碳浓度与氨气浓度严重超标,氧气含量不足,各环境因子与病原微生物相互作用,可能是导致鸡群发病的主要原因。  相似文献   

7.
基因表达水平与沙门氏菌感染关系的研究   总被引:1,自引:1,他引:0  
 为了研究鸡TLR4(toll like receptor 4)基因表达在调控鸡沙门氏菌感染中的作用,80只3日龄SPF鸡按随机分为2组,处理组经口注射鸡白痢沙门氏菌悬液108 CFU/mL 0.50 mL,对照组注射同剂量生理盐水。每个处理组分别在感染后1、3、7和14 d随机取8只鸡处死,迅速取脾脏样品用于RNA提取。采用SYBR GreenⅠ染料实时荧光定量PCR(QPCR),比较处理组和对照组TLR4基因mRNA相对表达量的变化。结果显示,在4个时间点,与对照组相比,处理组TLR4基因高表达,差异显著(P<0.05);尤其在感染后3和7 d,差异达到极显著水平(P<0.01)。结果表明,鸡沙门氏菌感染后,TLR4基因mRNA表达上调,TLR4基因在沙门氏菌感染中发挥重要作用。  相似文献   

8.
根据正交试验对大熊猫犬瘟热病毒(CDV-PA-1421株)在生物反应器中的培养工艺进行优化,确定关键技术参数。结果表明,大熊猫犬瘟热病毒悬浮培养最佳组合条件为:Vero细胞长成单层后,接种到生物反应器,细胞接种浓度为0.2×106/mL~0.4×106/mL,微载体浓度为8.0 g/L,加入MSVP培养基至工作体积。按0.01~0.1 感染复数(MOI)接种病毒,在37 ℃ pH7.2条件下培养96~120 h,细胞病变(CPE)达70%~80%时收获病毒上清液,即可获得高滴度病毒液。3批培养结果显示病毒培养工艺稳定,收获液病毒含量均在107.0~107.5 TCID50/0.1mL之间。  相似文献   

9.
为探讨白术和白头翁水煎液对鸡离体空肠运动张力的影响,采用离体器官试验法,以鸡的空肠平滑肌张力变化为指标,将鸡的离体空肠置于恒温通气台式液中,分别加入浓度为4.00g/L、8.00g/L和16.00g/L的白术和白头翁的水煎液,以观察白术和白头翁对不同肠管运动张力的影响。试验结果表明,白术水煎液能促进鸡离体空肠平滑肌收缩运动,使收缩张力和舒张张力增强,收缩振幅增大,其剂量越大作用越强,并呈量效关系。白头翁水煎液极显著抑制鸡离体空肠平滑肌的自律性收缩活动,可降低空肠运动张力,减小收缩幅度,加大剂量其抑制效果亦随之加强。  相似文献   

10.
为探究荨麻对子宫运动的影响及其可能机制,本试验用生物信号处理系统测定了浓度递增(0.5%、1.0%、2.0%、4.0%、8.0%和16.0%)的麻叶荨麻(Urtica cannabina,UC)醇提液对未孕大鼠离体子宫收缩频率、收缩张力和收缩幅度的影响,并用特异性M-受体阻断剂硫酸阿托品(atropine,A,2.5 μg/mL)和2.0% UC联合用药,分为3个处理: UC单独处理、UC+A和A+UC,观察UC对子宫收缩的影响是否与M-受体有关.结果显示,在UC浓度递增到4.0%时收缩频率较用药前显著增加(P <0.05);浓度递增到4.0%、8.0%时,收缩幅度较用药前极显著降低(P <0.01);但浓度递增UC对子宫收缩张力影响不显著(P >0.05).一次性加入2.0% UC后子宫收缩张力迅速增加并接近僵直,之后逐渐降低.无论UC+A或A+UC处理都使子宫收缩频率较用药前明显加快,收缩张力极显著增加(P <0.01),但2个联合用药处理组之间差异不显著(P >0.05);UC+A和A+UC处理组收缩张力较UC单独用药组均极显著降低(P <0.01).结果表明,UC可兴奋未孕大鼠离体子宫,A可缓解UC引起的子宫僵直或张力增加,但不能阻断UC引起的子宫收缩频率增加.提示UC对未孕大鼠离体子宫的兴奋作用和激动与M-受体有一定关系,但可能还存在其他机制.  相似文献   

11.
The effect of bombesin and of substance P was investigated in smooth muscle strips of the chicken crop. Bombesin in picomolar concentration (0.1×10-12–5×10-12mol/l) caused a concentration-related contraction of the muscle strips. Substance P in nanomolar concentration (0.1×10-9–10×10-9mol/l) was effective in the same manner. Tetrodotoxin (2×10-7mol/l) did not influence the contraction responses to either bombesin or substance P. The excitatory effect of bombesin and of substance P did not follow activation of cholinergic receptors since their effect on the crop smooth muscle was not antagonized by atropine (10-4mol/l) or by hexamethonium (10-4mol/l). Strips stored for 24 hours in the Tyrode's solution at 4°C without a supply of oxygen maintained their full sensitivity to bombesin and to substance P. These results are consistent with a direct action of bombesin and substance P on the crop smooth muscle.  相似文献   

12.
Selective muscarinic receptor antagonists were used to identify muscarinic receptor subtypes in equine trachealis strips. The M1 receptor antagonist pirenzepine (10–7 mol/L to 3 × 10–5 mol/L) and the M3 receptor antagonist 4-diphenylacetoxy-N-methylpiperidine (4-DAMP, 10–9 mol/L to 3 × 10–7 mol/L3) dose dependently inhibited the contractile responses to electrical field stimulation (EFS) and exogenous acetylcholine (ACh). Schild plots yielded a pA2 value for pirenzepine vs ACh of 6.75 ± 0.09, which is consistent with the affinity for M2 or M3 receptors, and a pA2 value for 4-DAMP vs ACh of 8.47 ± 0.09, which is in agreement with the affinity for M3 receptors. The M2 receptor antagonist gallamine (10–5 mol/L and 10–4 mol/L) did not affect the response of trachealis to exogenous ACh and low-frequency EFS (0.1–2 Hz) but decreased the responses to high-frequency EFS (4–16 Hz). These results suggest that the muscarinic receptors mediating contractions induced by ACh in equine tracheal smooth muscle are of the M3 subtype. The lack of an increase in the response to EFS following gallamine suggests that functional prejunctional inhibitory M2 receptors are not present on the cholinergic nerves innervating equine tracheal smooth muscle.  相似文献   

13.
信号硫化氢缓解植物盐碱胁迫机理备受关注。为探讨外源硫化氢对盐碱胁迫下植物氨基酸代谢的调控机制,采用盆栽土培试验,以裸燕麦品种‘定莜9号’为材料,设置盆土不添加盐碱和添加3.00 g·kg-1盐碱(摩尔比NaCl︰Na2SO4︰Na2CO3︰Na HCO3=12︰8︰1︰9)与抽穗期叶面喷蒸馏水和喷50μmol·L-1硫化氢供体硫氢化钠(NaHS)溶液,共4个处理。研究其对叶片中总氨基酸、丙二醛含量和籽粒产量的影响;运用液相色谱和质谱检测,采用主成分分析22种组成蛋白质的氨基酸中差异氨基酸,解析外源硫化氢对氨基酸代谢途径的调控效应。结果表明:在裸燕麦叶片中未检出高半胱氨酸。喷施NaHS溶液对盐碱胁迫下裸燕麦叶片中总氨基酸含量下降的缓解效应不显著,对盐碱胁迫诱导的丙二醛含量的升高和籽粒产量的下降有显著的缓解作用。主成分分析结果显示:盐碱胁迫下,喷施NaHS可显著下调裸燕麦叶片中α-酮戊二酸族的鸟氨酸和草酰乙酸族的天冬酰胺含量;显著上调α-...  相似文献   

14.
The responses of the vasculature of isolated, non-sensitized, bovine external ears to histamine and serotonin (5-HT) were evaluated while they were being perfused with Krebs-Henseleit solution, Histamine (10–5 mol/L to 5×10–3 mol/L) and 5-hydroxytryptamine (5-HT) (10–9 mol/L to 10–2 mol/L) caused increased vascular resistance. Mepyramine (10–7 mol/L), cimetidine (10–5 mol/L) and atropine (10–6 mol/L) inhibited the responses to histamine. The responses to 5-HT were inhibited by methysergide (10–9 mol/L) and potentiated by morphine (10–5 mol/L). These results suggest the presence of H1 and H2 histamine, and 5-HT receptors in bovine auricular vessels, all of which cause net vasoconstriction.  相似文献   

15.
硫化氢(H2S)信号在作物种子萌发中发挥着重要作用。为探讨外源H2S供体NaHS引发提高作物种子活力的作用及其生理机制,以裸燕麦种子为材料,分别用不同浓度NaHS (0、50、100、200、400、800、1600 μmol·L-1)引发18 h和800 μmol·L-1 NaHS引发不同时间(6、9、12、15、18、21 h),分析其发芽势(GP)、发芽率(GR)、发芽指数(GI)、活力指数(VI)和幼苗干重(DW)的变化,以确定适宜的NaHS引发浓度和引发时间。以未引发种子为对照(CK),同时设置H2O引发,研究800 μmol·L-1 NaHS引发18 h对种子H2S产生、贮藏物质含量和活性氧代谢的影响。结果表明,800 μmol·L-1 NaHS引发18 h可显著提高裸燕麦种子的GP、GR、GI和VI,但对DW的影响不大。NaHS引发对种子淀粉、可溶性糖、可溶性蛋白质、还原型抗坏血酸(ASA)、脱氢抗坏血酸(DHA)含量及ASA/DHA和抗坏血酸过氧化物酶活性无显著影响,但显著提高H2S和氧化型谷胱甘肽(GSSG)含量及细胞色素氧化酶(COX)、超氧化物歧化酶、过氧化氢酶和过氧化物酶活性,分别比CK提高了113.5%、14.4%、103.3%、6.1%、112.0%和120.5%;降低α-淀粉酶和β-淀粉酶活性及超氧阴离子、过氧化氢、丙二醛、还原型谷胱甘肽(GSH)含量、GSH/GSSG和质膜相对透性,分别下降了39.8%、53.6%、34.7%、36.1%、37.6%、29.2%、38.1%和11.9%。由此表明,NaHS引发可能通过提高种子H2S含量,从而调控抗氧化系统和激活COX活性,降低活性氧对质膜的损伤,增强细胞有氧呼吸代谢,提高裸燕麦种子活力。  相似文献   

16.
In order to study the metabolic profile of ostriches in relation to diet, 40 animals of both sexes were divided equally into two groups and fed two diets ad libitum consisting, on a dry matter basis, of the same commercial concentrate (60%) for the two groups and of corn silage (group A) or alfalfa hay (group B). In the morning, after about 12 h of fasting, blood was collected from the wing vein. The following haematological parameters were determined with an automatic system (Ektachem 250 analyser, Kodak): glucose, cholesterol, triglycerides, lactate (LAC), total protein (TP), uric acid, total bilirubin (Tbil), creatinine (CREA), calcium (Ca), magnesium (Mg), phosphorus (P), sodium (Na), potassium (K), chloride (Cl), iron (Fe), aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (AP), cholinesterase (ChE), α-amylase (Amyl), lipase (LIP) and γ-glutamyltrasferase (GGT). Diet significantly affected some parameters of the metabolic profile. Indeed, owing to the presence of alfalfa hay in the diet, group B showed, in comparison to group A, significantly higher values of uric acid (222.5 vs 387.5 mmol/L, p < 0.01), GGT (8.50 vs 11.3 U/L, p < 0.05), Tbil (8.50 vs 10.7 mmol/L, p < 0.05), Ca (2.41 vs 2.83 μmol/L, p < 0.01), Mg (1.01 vs 1.18 μmol/L, p < 0.05) and K (2.71 vs 3.16 μmol/L, p < 0.01). The levels of creatinine (27.3 vs 32.6 mmol/L, p < 0.05) and AST (344.9 vs 461.4 U/l, p < 0.01) were also higher for group B.  相似文献   

17.
The purpose of oocyte in vitro maturation is generation of mature oocytes that could support future development. Efforts have been made to enhance oocyte developmental competence by developing optimal culture conditions. The present study is conducted to determine melatonin effects on quality of polycystic ovarian syndrome (PCOS) oocytes when it has been added during in vitro maturation, and immature oocytes were cultured in defined conditioned medium with and without different melatonin concentrations. Melatonin could significantly improve nuclear maturation of PCOS oocytes (81.1% vs. 56.3%, P < 0.05 were achieved with 10?6 mol/L concentration). Cleavage rate was significantly higher in 10?5 mol/L concentration compared to untreated oocytes in PCOS (54% vs. 35%, respectively) and it was significantly higher with 10?6 mol/L concentration in the control group, 55% versus 38%, compared to untreated oocytes. This study showed that melatonin has the potential to induce oocyte nuclear maturation and guarantee fertilization potential. © 2016 Japanese Society of Animal Science  相似文献   

18.
《动物营养(英文)》2021,7(4):1115-1123
This study aimed to explore the mechanism underlying arginine-promoted myogenesis of myoblasts. C2C12 cells were cultured with a medium containing 0.1, 0.4, 0.8, or 1.2 mmol/L arginine, respectively. Cell proliferation, viability, differentiation indexes, cytoplasmic Ca2+ concentration, and relative mRNA expression levels of myogenic regulatory factors (MRF) and key Ca2+ channels were measured in the absence or presence of 2 chemical inhibitors, dantrolene (DAN, 10 μmol/L) and nisoldipine (NIS, 10 μmol/L), respectively. Results demonstrated that arginine promoted myogenic differentiation and myotube formation. Compared with the control (0.4 mmol/L arginine), 1.2 mmol/L arginine upregulated the relative mRNA expression levels of myogenin (MyoG) and Myomaker at d 2 during myogenic induction (P < 0.05). Cytoplasmic Ca2+ concentrations were significantly elevated by arginine supplementation at d 2 and 4 (P < 0.05). Relative mRNA expression levels of Ca2+ channels including the type 1 ryanodine receptor (RyR1) and voltage-gated Ca2+ channel (Cav1.1) were upregulated by 1.2 mmol/L arginine during 2-d myogenic induction (P < 0.01). However, arginine-promoted myogenic potential of myoblasts was remarkably compromised by DAN and NIS, respectively (P < 0.05). These findings evidenced that the supplementation of arginine promoted myogenic differentiation and myotube formation through increasing cytoplasmic Ca2+ concentration from both extracellular and sarcoplasmic reticulum Ca2+.  相似文献   

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