运动对创伤后应激障碍大鼠单胺类递质和炎症的影响

目的:通过条件性恐惧模型大鼠来评估跑台运动的抗创伤后应激障碍(PTSD)作用,并探讨运动对PTSD影响的可能分子机制。方法:将50只雄性SD大鼠随机分为对照组(control)、条件恐惧模型组(FC)、消退组(EXT)、消退+运动组(EXT+EX)和消退+舍曲林组(EXT+SER)。通过条件恐惧消退保持测试来测试情境恐惧记忆;通过自发活动测试和高架迷宫测试来测试大鼠焦虑样行为;利用酶联免疫法(ELISA)检测大鼠海马肿瘤坏死因子-α(TNF-α)和白细胞介素-1β(IL-1β)水平;利用高效液相色谱(HPLC)技术测定大鼠海马和前额叶皮质中单胺类神经递质及其代谢产物水平。结果:FC组大鼠的僵住时间增加(P 0.001),进入开臂次数百分比(P 0.01)和开臂时间百分比(P 0.001)减少,而运动和舍曲林均逆转了这些行为缺陷(P 0.05)。FC大鼠海马中TNF-α水平(P 0.05)和IL-1β水平(P 0.05)显著升高,FC大鼠海马和皮层中的去甲肾上腺素(NE)水平(P 0.05)以及多巴胺(DA)水平(P 0.05)显著升高。而舍曲林给药显著降低了海马中TNF-α水平(P 0.05),跑台运动和舍曲林给药显著均显著降低了海马中IL-1β水平(运动:P 0.05;舍曲林:P 0.01)和5-羟色胺(5-HT)代谢产物5-羟吲哚乙酸(5-HIAA)水平(P 0.05),同时显著降低了皮层中NE水平(P 0.01)和DA水平(P 0.05)。结论:跑台运动改善了条件恐惧模型大鼠的情境恐惧记忆和焦虑样行为。单胺类神经递质NE和DA以及炎性因子TNF-α和IL-1β可能参与了跑台运动对PTSD的缓解作用。     

慢性间歇性缺氧对阻塞性睡眠呼吸暂停低通气综合征模型大鼠抑郁的影响及机制

目的:通过建立具有阻塞性睡眠呼吸暂停低通气综合征(obstructive sleep apnea-hypopnea syndrome,OSAHS)病理生理特性的慢性间歇性缺氧(chronic intermittent hypoxia,CIH)动物模型,研究CIH对大鼠抑郁状态的影响及可能机制。方法:设立空白对照组(CON),慢性间歇性缺氧模型组(CIH)和缺氧后复氧组(RH),每组SD大鼠8只。PET/CT脑部显像观察代谢水平,糖水偏好实验、旷场实验、强迫游泳实验评价抑郁状态,电镜下观察海马CA1区突触形态、数量,酶联免疫法(ELISA)测量海马区PSD-95、BDNF、5-HT、DA、NE含量。结果:与CON组相比,CIH组旷场实验中央活动路程比降低(P0.05),强迫游泳不动时间延长(P0.05),电镜下突触数量减少(P0.05),海马组织5-HT、NE、BDNF、PSD-95表达水平下降(P0.05,P0.01);RH组中央活动路程比降低(P0.05),海马组织5-HT、BDNF表达下降(P0.05)。与CIH组相比,RH组大鼠海马组织5-HT含量增高(P0.05)。结论:CIH可一定程度增加抑郁的发生风险,机制可能与海马区5-HT、BDNF表达水平降低和突触可塑性改变有关。纠正缺氧可部分改善神经损伤。     

颈交感干离断缓解快速眼动睡眠剥夺大鼠学习记忆障碍

目的:观察颈交感干离断(TCST)对快速眼动睡眠剥夺(RSD)大鼠空间学习记忆的作用及其潜在机理。方法:32只成年雄性SD大鼠分成假手术组(sham)、RSD组、TCST组和TCST干预的RSD组(RSD+TCST组)。采取改良的多站台水环境法建立大鼠RSD模型。选取Morris水迷宫实验检测各组大鼠空间学习记忆能力,Western Blot检测caspase-3蛋白表达,通过ELISA评估海马组织去甲肾上腺素(NE)、肿瘤坏死因子α(TNF-α)、白细胞介素6(IL-6)和白细胞介素1β(IL-1β)的水平。结果:TCST明显提高了RSD大鼠的空间学习记忆能力(P 0.05),TCST显著抑制RSD大鼠海马组织NE的释放(P 0.05)、炎症反应(P 0.05)与凋亡(P 0.05)。结论:TCST可通过抑制交感神经活动,缓解海马组织炎症与减少细胞凋亡来改善RSD大鼠空间学习记忆障碍。     

TRAF6对抑郁症大鼠海马区神经元细胞损伤和免疫紊乱的调节

目的 探讨肿瘤坏死因子受体相关因子6(TRAF6)对慢性不可预知性轻度应激(CUMS)大鼠的抗抑郁作用。方法 将40只健康SPF级SD大鼠随机分为对照组、模型组(CUMS组)、CUMS+sh RNA-NC组和CUMS+TRAF6-sh RNA组,每组10只。除对照组外,所有大鼠每天随机接受CUMS刺激,5周后,分别向CUMS+sh RNA-NC组和CUMS+TRAF6-shRNA组大鼠海马区注射慢病毒包被的sh RNA-NC和TRAF6-shRNA序列。RT-PCR和Western blot检测TRAF6 m RNA和蛋白的表达; ELISA检测大鼠血清中5-羟色胺(5-HT)、5-羟吲哚乙酸(5-HIAA)、TNF-α、i NOS、IL-6和IL-10的含量;酶法测定大鼠血清血脂; HE染色观察海马区病理状况; TUNEL染色检测海马区细胞凋亡情况; Western blot检测海马谷氨酸转运体(GLT-1)和脑源性神经营养因子(BDNF)及凋亡蛋白的表达。结果 与对照组相比,CUMS组大鼠海马区TRAF6 m RNA和蛋白表达量明显上调(P 0. 05),GLT-1和BDNF蛋白表达显著下调(P 0. 05),血清中5-HT和5-HIAA水平显著较低(P 0. 05),TC、TG和LDL-c水平较高(P 0. 05),HDL-c水平较低(P 0. 05);大鼠血脂代谢紊乱,海马区神经元数量减少,核固缩;凋亡细胞数目明显较多(P 0. 05),Bax/Bcl-2及cleaved Caspase3/Caspase3比值显著上调(P 0. 05); TNF-α、i NOS、IL-6和IL-10含量明显较高(P 0. 05)。与CUMS组相比,CUMS+TRAF6-sh RNA组大鼠海马区TRAF6 m RNA和蛋白表达量明显下调(P 0. 05),GLT-1和BDNF蛋白表达显著上调,血清5-HT和5-HIAA水平较高(P 0. 05),TC、TG和LDL-c水平较低(P 0. 05),HDL-c水平较高(P 0. 05);海马区神经元完整,很少有核固缩;凋亡细胞数目明显较少(P 0. 05),Bax/Bcl-2及cleaved Caspase3/Caspase3比值显著下调(P 0. 05),TNF-α、i NOS、IL-6含量显著较低(P 0. 05),IL-10含量较高(P 0. 05)。结论 敲低TRAF6水平治疗抑郁症大鼠可能是通过调节大鼠神经递质、抑制海马神经元凋亡并抑制炎症反应来实现。     

启神胶囊对全脑反复缺血再灌注大鼠脑内单胺类神经递质含量的影响

为了探讨启神胶囊对全脑反复缺血再灌注大鼠脑内单胺类神经递质的影响 ,Wister大鼠 ,采用 4-血管反复缺血再灌注造模 ,分正常对照组、模型组、模型喂药组 ,30天后取脑 ,用HPLC—ECD法测定 ,结果表明 ,模型大鼠海马组织中NE、MHPG、5—HT含量下降 ,与正常对照组差异显著 (p <0 .0 5 ) ;中药组大鼠海马组织中NE、MHPG、5—HT、HVA比模型鼠显著上升 (p <0 .0 5 )。模型大鼠大脑皮层中NE、MHPG、DA、HVA含量明显低于对照组 ,中药组NE、HVA含量均比模型组显著提高 (p <0 .0 5 ) ;MHPG、DA虽也有提高 ,但无统计学差异 ;5—HT含量 ,模型组高于对照组 (p <0 0 5 ) ,中药组低于模型组 (p <0 .0 5 )。启神胶囊能影响全脑缺血再灌注大鼠单胺类神经递质的代谢     

毛蕊花糖苷通过调控BDNF-TrkB信号通路改善CUMS大鼠的抑郁样行为

目的:观察毛蕊花糖苷(acteoside)对慢性不可预见性温和应激(chronic unpredictable mild stress,CUMS)大鼠抑郁样行为的影响,并探讨脑源性神经营养因子-原肌球蛋白受体激酶B(brain-derived neurotrophic factor-tropomyosin receptor kinase B,BDNF-TrkB)信号通路在其中的作用机制。方法:采用CUMS结合孤养的方式制备抑郁模型大鼠,成模后随机分为模型组、盐酸氟西汀(20 mg/kg)组和毛蕊花糖苷(30 mg/kg、60 mg/kg和120 mg/kg)组,每组18只,另取18只正常大鼠作为对照组,连续灌胃给药3周。采用强迫游泳实验和糖水偏好实验检测大鼠抑郁样行为的变化;免疫荧光和Western blot法检测大鼠海马BDNF-TrkB信号通路相关蛋白的表达情况;ELISA法检测脑组织中单胺类神经递质5-羟色胺(5-HT)、多巴胺(DA)和去甲肾上腺素(NE)的含量。结果:与对照组比较,模型组大鼠强迫游泳不动时间明显延长,糖水偏好量明显下降,海马BDNF和TrkB的表达均明显降低,脑组织中5-HT、DA和NE含量均显著减少;与模型组比较,盐酸氟西汀组和毛蕊花糖苷各剂量组以上各检测指标均得到显著逆转(P0.05)。结论:毛蕊花糖苷可能通过上调海马BDNF-TrkB信号通路、增加脑内单胺类神经递质含量而改善CUMS大鼠的抑郁样行为。     

不同睡眠剥夺时间对大鼠海马和前额皮层Ng、PKC、CaMKⅡ mRNA表达的影响

目的：探讨不同睡眠剥夺时间对大鼠海马和前额皮层神经颗粒素（Ng)、蛋白激酶C (PKC)、 Ca2+ -CaM依赖性蛋白激酶Ⅱ（CaMKⅡ）mRNA表达的影响。方法： 雄性Wistar大鼠随机分为3组,即24 h实验组、48 h实验组和72 h实验组,每组再分为睡眠剥夺组（SD组）和对照组（C组）。利用睡眠剥夺箱建立大鼠SD模型,Trizol一步法提取海马和前额皮层总RNA,用SYBRA　green Ⅰ荧光定量RT-PCR测定Ng、PKC和CaMKⅡ mRNA水平。结果： (1)大鼠海马Ng mRNA水平在睡眠剥夺24 h、48 h和72 h后,较对照组均显著降低（P＜0.05）,PKC和CaMKⅡ mRNA水平在睡眠剥夺48 h和72 h后显著降低（P＜0.05）; (2)在睡眠剥夺24 h和48 h后,大鼠前额皮层Ng、PKC和 CaMKⅡ mRNA水平较对照组有降低趋势,在睡眠剥夺72 h后均显著降低（P＜0.05）。结论： 睡眠剥夺可以使大鼠海马和前额皮层Ng、PKC和CaMKⅡ mRNA表达水平降低,且随着睡眠剥夺时间的延长,降低更为明显,这可能是睡眠剥夺损害认知功能的原因之一。     

慢性不完全性睡眠剥夺对幼鼠学习记忆的影响

目的：探讨慢性不完全性睡眠剥夺对幼鼠学习记忆能力的影响及其可能机制。方法：建立慢性不完全性睡眠剥夺动物模型，并测定其空间学习记忆能力，同时对幼鼠大脑前额皮质及海马神经元性一氧化氮合酶(nNOS)的表达进行分析。结果：睡眠剥夺组幼鼠完成预定任务所需的时间及发生错误的次数均超过正常对照组。睡眠剥夺组的nNOS在前额皮质区域阳性、强阳性表达面积及在海马区域强阳性表达面积均大于正常对照组。结论：慢性不完全性睡眠剥夺会影响幼鼠的学习记忆能力，而前额皮质及海马中nNOS表达水平的下降可能是慢性不完全性睡眠剥夺影响未成熟脑学习记忆能力的机制之一。     

右美托咪定对快速眼动睡眠剥夺大鼠学习记忆障碍的影响

目的:探讨右美托咪定对快速眼动(REM)睡眠剥夺大鼠学习记忆障碍的影响。方法:将64只健康雄性SD大鼠随机分为对照组(control)、快速眼动睡眠剥夺组(RSD)、右美托咪定组(DEX)和右美托咪定干预的快速眼动睡眠剥夺组(RSD+DEX)。每组16只。应用改良多平台水环境法建立大鼠快速眼动睡眠剥夺模型,通过腹腔内注射给予大鼠右美托咪定,采用Morris水迷宫检测大鼠空间学习记忆能力,采用尼氏染色法检测大鼠海马神经元形态学改变,同时应用试剂盒检测大鼠海马组织匀浆中丙二醛(MDA)含量及超氧化物歧化酶(SOD)活性。结果:与RSD组大鼠相比,RSD+DEX组大鼠逃避成功潜伏期趋于缩短(P 0. 05),穿越平台次数与目标象限时间百分比均明显增加(均P 0. 05),MDA含量减少,SOD活性均增加(P 0. 05),海马CA1区神经元排列较规则,尼氏小体明显增加。结论:右美托咪定能够改善REM睡眠剥夺大鼠学习记忆损伤,这可能与右美托咪定缓解REM睡眠剥夺大鼠海马神经细胞氧化应激和恢复受损细胞有关。     

睡眠剥夺对HSP70表达及脑超微结构的影响

目的：观察睡眠剥夺（SD）后大鼠脑组织HSP70表达的变化及对超微结构的影响。方法：44只雄性SD大鼠随机分为11组，每组4只，免疫组织化学方法检测HSP70的表达，电镜观察海马超微结构的变化。结果：睡眠剥夺后12小时即可在大脑皮质及海马观察到HSP70阳性细胞，2—3天数量达到高峰，7天时明显下降。白天睡眠剥夺12小时（SDd12h）组HSP70阳性细胞数较夜晚睡眠剥夺12小时（SDn12h）组多（P〈0．05）。RS组大脑皮质HSP70阳性细胞数较白天睡眠剥夺1天（SDd1d）组减少（P〈0．05）。白天睡眠剥夺3天（SDd3d）海马出现超微结构改变，白天睡眠剥夺7天（SDd7d）后改变更加明显。结论：睡眠剥夺可影响大鼠脑组织HSP70表达及超微结构。     

Pain and Effusion and Quadriceps Activation and Strength

Context:

Quadriceps dysfunction is a common consequence of knee joint injury and disease, yet its causes remain elusive.

Objective:

To determine the effects of pain on quadriceps strength and activation and to learn if simultaneous pain and knee joint effusion affect the magnitude of quadriceps dysfunction.

Design:

Crossover study.

Setting:

University research laboratory.

Patients or Other Participants:

Fourteen (8 men, 6 women; age = 23.6 ± 4.8 years, height = 170.3 ± 9.16 cm, mass = 72.9 ± 11.84 kg) healthy volunteers.

Intervention(s):

All participants were tested under 4 randomized conditions: normal knee, effused knee, painful knee, and effused and painful knee.

Main Outcome Measure(s):

Quadriceps strength (Nm/kg) and activation (central activation ratio) were assessed after each condition was induced.

Results:

Quadriceps strength and activation were highest under the normal knee condition and differed from the 3 experimental knee conditions (P < .05). No differences were noted among the 3 experimental knee conditions for either variable (P > .05).

Conclusions:

Both pain and effusion led to quadriceps dysfunction, but the interaction of the 2 stimuli did not increase the magnitude of the strength or activation deficits. Therefore, pain and effusion can be considered equally potent in eliciting quadriceps inhibition. Given that pain and effusion accompany numerous knee conditions, the prevalence of quadriceps dysfunction is likely high.Key Words: arthrogenic muscle inhibition, central activation failure, voluntary activation, muscles

Key Points

• Knee pain and effusion resulted in arthrogenic muscle inhibition and weakness of the quadriceps.
• The simultaneous presence of pain and effusion did not increase the magnitude of quadriceps dysfunction.
• To reduce arthrogenic muscle inhibition and improve muscle strength, clinicians should employ interventions that target removing both pain and effusion.

Quadriceps weakness is a common consequence of traumatic knee joint injury^1,2 and chronic degenerative knee joint conditions.^3,4 Arthrogenic muscle inhibition (AMI), a neurologic decline in muscle activation, results in quadriceps weakness and hinders rehabilitation by preventing gains in strength.⁵ The inability to reverse AMI and restore muscle function can lead to decreased physical abilities,⁶ biomechanical deficits,⁷ and possibly reinjury.⁵ Furthermore, researchers^8,9 have suggested that quadriceps weakness resulting from AMI may place patients at risk for developing osteoarthritis in the knee. In light of the substantial influence of quadriceps AMI on these clinically relevant outcomes, we need to improve our understanding of the factors that contribute to this neurologic decline in muscle activity so efforts to target and reverse it can be implemented and gains in strength can be achieved more easily.Joint injury and disease are accompanied by numerous sequelae (ie, pain, swelling, tissue damage, inflammation), so ascertaining which one ultimately leads to neurologic muscle dysfunction is difficult. Whereas a joint effusion can result in AMI,^10–12 the effects of pain are less understood despite many clinicians attributing AMI to pain. Using techniques that introduce knee pain without accompanying injury may provide insights into the role of pain in eliciting AMI.The degree of knee joint damage may play a role in the quantity of AMI that manifests. Hurley et al^13,14 demonstrated that quadriceps AMI, measured using an interpolated-twitch technique, was greater in patients with extensive traumatic knee injury (eg, fractured tibial plateau, ruptured medial collateral ligament, and medial meniscectomy) than patients with isolated joint trauma (ie, isolated anterior cruciate ligament [ACL] rupture). Similarly, patients with more knee joint symptoms (ie, greater number of symptoms and increased severity of symptoms) may present with greater magnitudes of quadriceps inhibition. Recently, investigators¹⁵ have suggested that patients with more pain display less quadriceps strength, supporting this tenet. Given that effusion and pain often present simultaneously with joint injuries and diseases, such as ACL injury and osteoarthritis, examining both the isolated and cumulative effects of these sequelae appears warranted to determine if they influence the magnitude of muscle inhibition.Experimental joint-effusion and pain models are safe and effective experimental methods that allow for the isolated examination of their effects on muscle function. The effusion model, whereby sterile saline is injected directly into the knee joint capsule,⁷ produces a clinically relevant magnitude of the joint effusion that may be present with traumatic injury. Effusion is thought to activate group II afferents responding to stretch or pressure,^16–18 which in turn may facilitate group Ib interneurons and result in quadriceps AMI.⁵ The pain model involves injecting hypertonic saline into the infrapatellar fat pad to produce anteromedial knee pain similar to that described in patients with patellofemoral pain syndrome.¹⁹ Pain is considered to initiate AMI through activation of group III and IV afferents that act as nocioceptors to signal damage or potential damage to joint structures.^16–18 The firing of these afferents then may lead to facilitation of group Ib interneurons, the flexion reflex, or the gamma loop, ultimately resulting in quadriceps inhibition.²⁰ Thus, these models allow us to create symptoms that are associated with knee injury and have the added benefit of providing a way to examine their effects in isolation.Therefore, the purpose of our study was to determine the effects of pain on quadriceps strength and activation and to learn if simultaneous pain and knee joint effusion would affect the magnitude of quadriceps dysfunction. We hypothesized that pain alone would result in quadriceps inhibition and that the magnitude of inhibition would be greater when effusion and pain were present simultaneously.     

即早基因c-fos与脑血管病及学习记忆

即早基因c-fos是广泛存在于原核细胞和真核细胞的高度保守基因.在正常情况下,c-fos基因参与细胞生长、分化、信息传递、学习和记忆等生理过程,而在病理情况下c-fos基因表达及调控变化与多种疾病的发生和发展有关.C-fos在中枢神经系统的某些部位可有基础水平的表达,但表达很低,当受到如脑缺血、脑出血、痫性发作、应激等刺激后,其在数十分钟内做出反应,在对外界刺激-转录耦联的信忠传递过程中起着核内第三信使的重要作用.     

Opportunities and challenges in the prevention and control of cancer and other chronic diseases: children's diet and nutrition and weight and physical activity

OBJECTIVE: The purpose of this article is to review the role of behavioral research in disease prevention and control, with a particular emphasis on lifestyle- and behavior-related cancer and chronic disease risk factors--specifically, relationships among diet and nutrition and weight and physical activity with adult cancer, and tracking developmental origins of these health-promoting and health-compromising behaviors from childhood into adulthood. METHOD: After reviewing the background of the field of cancer prevention and control and establishing plausibility for the role of child health behavior in adult cancer risk, studies selected from the pediatric published literature are reviewed. Articles were retrieved, selected, and summarized to illustrate that results from separate but related fields of study are combinable to yield insights into the prevention and control of cancer and other chronic diseases in adulthood through the conduct of nonintervention and intervention research with children in clinical, public health, and other contexts. RESULTS: As illustrated by the evidence presented in this review, there are numerous reasons (biological, psychological, and social), opportunities (school and community, health care, and family settings), and approaches (nonintervention and intervention) to understand and impact behavior change in children's diet and nutrition and weight and physical activity. CONCLUSIONS: Further development and evaluation of behavioral science intervention protocols conducted with children are necessary to understand the efficacy of these approaches and their public health impact on proximal and distal cancer, cancer-related, and chronic disease outcomes before diffusion. It is clear that more attention should be paid to early life and early developmental phases in cancer prevention.