Effect of regular swimming exercise to duration-intensity on neurocognitive function in cerebral infarction rat model

Objective: This study investigated the effect of regular swimming exercise according to the duration-intensity on neurocognitive function in a cerebral infarction rat model.

Methods: Forty male Sprague–Dawley 10-week-old rats, weighing 300 ± 50 g, were subjected to photothrombotic cerebral infarction. The remaining 36 rats were randomly divided into four groups (n = 9 per group: non-exercise (group A); swimming exercise of short duration-intensity (5 min/day, group B); swimming exercise of moderate duration-intensity (10 min/day, group C); and swimming exercise of long duration-intensity (20 min/day, group D). Exercise was performed five times a week for 4 weeks, beginning the day after cerebral infarction. Neurocognitive function was evaluated with the Morris water maze test. Immunohistochemistry and western blot analysis examined brain-derived neurotrophic factor (BDNF) and vascular endothelial growth factor (VEGF) at 4 weeks postinfarction.

Results: At 4 weeks postinfarction, escape latency was found to be shorter in group C than in any of groups A, B, or D. Immunohistochemistry revealed the most significant immunoreactivity for BDNF and VEGF in group C. Western blot analysis demonstrated that BDNF and VEGF proteins were markedly expressed in group C.

Conclusions: Regular swimming exercise of moderate duration-intensity may be the most effective exercise protocol for the recovery of neurocognitive function in cerebral infarction rat model.     

松果腺切除对长期游泳老龄小鼠MDA影响的对比研究

为研究长期游泳运动老龄小鼠脂质过氧化水平的降低是否与刺激了松果腺释放褪黑素有关,将松果腺切除12月龄昆明种小鼠分为手术组(n=36)、非手术组(n=36)和假手术组(n=12),前2组又各分为对照组、60min组和60min+3%体质量负荷组,对其血清中的MDA浓度进行对比研究.结果:雄性小鼠非手术组中MDA浓度60min组及60min+3%负荷组均显着低于手术同负荷组(P<0.05,P<0.01).雌性小鼠,非手术组60min组MDA浓度显着低于手术组(P<0.05).而在60min+3%负荷组,手术组要显着低于非手术组(P<0.05).提示:长期运动训练降低血清脂质过氧化水平,可能与交感神经兴奋性升高刺激松果腺内褪黑素的合成和释放有关;如果选择负荷不当,会对松果腺机能产生抑制,而对机体抗氧化能力的提高产生负面影响.     

Behavioral models in mice. implication of the alpha noradrenergic system

1. The mechanism of action of drugs might change according to the test used. Several noradrenergic drugs were tested in order to understand their implication in the mobility tests.

2. It was found that clonidine, an Alpha 2 agonist, acted differently according to the tast used. It provoked sedation in spontaneous activity test, and anti-immobility effects in the other tests.

3. Tall suspension test is able to show the double acting of clonidine.

4. Idazoxan might act either as an alpha 2 antagonist or as partial alpha 2 agonist. TST shown the unexpected partial alpha agonist effect of the molecule.

5. Forced swimming test is more specific for predicting antidepressant activity than tail suspension test which is close to a spontaneous activity model.     

Nontraumatic glenohumeral instability and coracoacromial impingement in swimmers

Competitive swimming is one of the most demanding and time-consuming sports. Swimmers at elite level practice 20–30 h per week. During 1 year's practice, the average top level swimmer performs more than 500,000 stroke revolutions per arm. These innumerable repetitions over many years of hard training together with an increasing muscular imbalance around the shoulder girdle seem to be the main etiological factors in the development of the overuse syndrome swimmer's shoulder. Shoulder pain in swimmers has in general been regarded as synonymous with coracoacromial impingement, i.e. anterior shoulder pain due to rotator cuff tendinitis, but new knowledge suggests that a concomitant glenohumeral instability plays an additional role. The diagnostic complexity of the problem is as challenging as the search for the gold standard of treatment. The condition should ideally be diagnosed as early as possible, and intensive functional rehabilitation of the shoulder girdle including the scapular muscles should be started in order to restore muscle balance. The surgical possibilities include subacromial decompression in cases of purely mechanical impingement. If a painful glenohumeral instability persists after intensive functional rehabilitation, anterior capsulolabral reconstruction can be performed. Still, however, short- and long-term results show that surgery is less successful in elite athletes involved in overhead sports. Prevention protocols include education of coaches in primary injury prophylaxis and the institution of resistance strength training in prepubescent swimmers. Emphasis should be made to improve muscular balance around the glenohumeral and scapulothoracic joints.     

Active behaviors in the rat forced swimming test differentially produced by serotonergic and noradrenergic antidepressants

This study demonstrated that distinct patterns of active behaviors are produced by antidepressants that selectively inhibit norepinephrine (NE) or serotonin (5-HT) uptake in the rat forced swimming test (FST). A behavior sampling technique was developed to score the active behaviors swimming, climbing and diving, as well as immobility. The rat's behavior was recorded at the end of each 5-s period during the test session. The sampling technique was both reliable, as demonstrated by test-retest reliability and inter-rater reliability, and valid, as shown by comparison to the timing of behavior durations. Five different antidepressant drugs which block monoamine uptake and two 5-HT_1A receptor agonists were shown to decrease immobility in the FST; however, they produced distinct patterns of active behaviors. The selective NE uptake inhibitors desipramine and maprotiline selectively increased climbing, whereas the selective serotonin reuptake inhibitors (SSRIs) fluoxetine, sertraline and paroxetine selectively increased swimming. The 5-HT_1A receptor agonists 8-OH-DPAT and gepirone also selectively increased swimming. These results show that:1) SSRIs are not false negatives in the FST; 2) at least two behaviorally distinct processes occur in the FST; and 3) enhancement of NE neurotransmission may mediate climbing in the FST, whereas enhancement of 5-HT neurotransmission may mediate swimming.     

运动训练对雄性大鼠垂体─性腺轴功能的影响

本研究通过使用自己制造的大鼠流动水游泳池，对雄性大鼠进行了６周递增负荷的游泳训练，以此来探讨运动训练对大鼠垂体－性腺轴功能的影响，结果显示：与安静对照大鼠相比，训练大鼠的一般状态较差，血清睾酮水平显著降低（Ｐ＜０．０５），血清睾酮／皮质酮比值平均降低了３０％以上；而血清ＬＨ和ＦＳＨ水平未见明显变化。通过对大鼠睾丸组织ＬＨ／ＣＧ受体的测定，显示运动训练虽未引起其最大结合量的改变，却能使其解离常数显著升高（Ｐ＜０．０５）。提示此种训练可能通过降低睾丸ＬＨ／ＣＧ受体对垂体分泌ＬＨ的亲和力，从而影响睾酮的合成。     

小鼠低温游泳脑缺血模型的建立及在注射液量效关系上的应用

目的:建立一种新的脑缺血小鼠模型,用标准的注射液验证模型的可靠性。方法:小鼠分成3组:生理盐水组,尼莫地平组(1.0 mg/kg)和三七总皂苷组(120 mg/kg)。静脉注射25m in后,动物负重5%体重,在10~10.5℃的水中游泳5m in,取出,断头,记录断头的喘气持续时间。小鼠分别注射尼莫地平0.3、0.7、1.0、1.5 mg/kg或三七总皂苷60、80、120、160 mg/kg,同上法操作,探讨两种药物的量效关系。结果:和生理盐水组比较,两个药物能显著延长小鼠断头的喘气持续时间(P<0.01)。尼莫地平的量效关系方程式为:y=27.74919x 18.79446;三七总皂苷的量效关系方程式为:y=0.13347x 20.51017,二者的量效关系均显著(P<0.05,P<0.01)。结论:新的方法能够用于评价药物的抗脑缺血作用。     

高能合剂对低氧鼠运动耐力和某些生化指标的影响

为提高高原劳动能力,我们研制了含有多种糖、维生素、氨基酸和无机盐的高能合剂。在小白鼠减压缺氧(模拟海拔高度10000m)游泳实验中,高能合剂组和对照组的存活时间分别为:72.3±1.3min和58.8±1.2min(P相似文献   

冷水游泳对去肾上腺大鼠下丘脑,垂体和血浆AVP含量的影响

ＡＶＰ主要合成于下丘脑的室旁核和视上核，正常情况下，每毫升血浆ＡＶＰ含量在１０ｐｇ以下，近年来的研究表明，疼痛、手术、应激等强刺激可引起ＡＶＰ大量释放，血浆中的ＡＶＰ含量可达１００ｐｇ以上。由于ＡＶＰ可使血管平滑肌收缩，并具ＣＲＦ样作用，可促进垂体释放ＡＣＴＨ，因此被认为是一种应激激素，而下丘脑－垂体－肾上腺皮质轴被认为是经典的应激系统。本工作旨在通过去除应激轴上的肾上腺这一环节，来验证ＡＶＰ是否