豚鼠前列腺Cajal间质细胞的超微结构特点及功能

目的:观察豚鼠前列腺Cajal间质细胞(interstitial cells of Cajal,ICCs)的超微结构特点以及ICCs和前列腺神经及平滑肌细胞之间的超微结构联系。方法:制作豚鼠前列腺组织切片并进行免疫荧光染色,使用酪氨酸激酶受体(c-Kit)抗体标记ICCs。制作豚鼠前列腺超薄组织切片,在透射电镜下寻找ICCs并观察其超微结构特点以及与周围神经、平滑肌细胞之间的超微结构联系。结果:免疫荧光标记发现豚鼠前列腺间质内有较多的c-Kit阳性ICCs。电镜下发现豚鼠前列腺组织内存在和c-Kit阳性ICCs形态、分布一致,符合典型胃肠道ICCs超微结构特点的间质细胞,这些前列腺ICCs分布于平滑肌细胞之间,与相邻的神经末梢形成典型的突触样连接,和周围的平滑肌细胞之间紧密相连。结论:豚鼠前列腺ICCs具有介导前列腺神经信号,调控平滑肌活动的超微形态学基础。     

豚鼠前列腺Cajal间质细胞的分离、培养及其鉴定

目的探索豚鼠前列腺的Cajal间质细胞(interstitial cells of Cajal,ICCs)的原代分离、培养及鉴定方法。方法无菌条件下分离出前列腺组织,采用酶消化法分离细胞,将细胞悬液接种于含干细胞因子的DMEM培养基中进行培养。倒置显微镜下观察细胞贴壁和形态,用酪氨酸蛋白激酶受体c-Kit特异性抗体标记细胞,免疫荧光法鉴定。结果培养24 h后的细胞贴壁良好,可见胞体为梭形,有2个或多个突起。随着培养时间的增长,突起彼此相互连接形成网络结构。该类细胞c-Kit抗体荧光染色阳性。结论用酶消化法可成功分离和培养成年豚鼠前列腺ICCs,可用于前列腺ICCs的电生理学研究。     

豚鼠输尿管Cajal间质细胞毒蕈碱受体的表达及功能研究

目的研究毒蕈碱受体在豚鼠输尿管Cajal间质细胞（ICC）上的表达,初步探讨ICC在胆碱能神经递质传递中的作用。方法将20只豚鼠随机分成对照组和实验组,进行输尿管肌条实验,观察在卡巴胆碱作用下输尿管肌条的收缩幅度和频率的变化;10只豚鼠,将输尿管进行固定、撕片和荧光染色,检测豚鼠输尿管毒蕈碱受体亚型（M1-M5）在ICC上的表达情况。结果卡巴胆碱作用后,实验组肌条的收缩幅度为0 g,频率为0次/分,对照组的幅度为（0.106±0.021）g,频率为（4.900±0.875）次/分,两组差异显著（P〈0.01）。免疫荧光双标显示,输尿管ICC仅表达M2、M3受体亚型。结论胆碱能神经可能通过ICC来调控输尿管平滑肌。     

红霉素对家兔结肠平滑肌条收缩活动的兴奋作用

通过家兔结肠离体平滑肌条实验，观察红霉素（1．4、14μmol/L及0．14、1．4mmol/L)对结肠自发收缩活动的影响。结果表明：1．4μmol/L红霉素对结肠各部位肌条的收缩活动无明显影响；14μmol/L红霉素增加结肠头端环行肌（CMPC）和结肠尾端环行肌（CMDC）的收缩幅度和频率，但对结肠头端纵行肌（LMPC）和结肠尾端纵行肌（LMDC）的收缩活动无明显影响；0．14和1．4mmol/L红霉素明显增加结肠各部位肌条的收缩幅度（LMDC除外）和频率，同时增大CMPC、LMDC和CMDC的张力。异搏定（1μmol/L）部分阻断红霉素（0．14mmol/L）对LMPC和CMDC收缩幅度和频率的兴奋作用；六甲溴铵（10μmol/L）、阿托品（1μmol/L）和L－精氨酸（1μmol/L）不影响红霉素（0．14mmol/L)的兴奋作用。上述结果表明，红霉素兴奋家兔结肠头端和尾端纵行肌和环行肌的自发收缩活动，该兴奋作用部分与Ca^2 通道有关，但与胆碱能途径和NO合成无关。     

长爪沙鼠胃肠道Cajal间质细胞的形态学

目的 探讨长爪沙鼠胃肠道Cajal间质细胞（ICCs）的形态和分布规律。 方法 采用10只成年长爪沙鼠,体重50~70g,取胃、小肠、结肠制作冷冻切片,结合全层铺片的c-Kit免疫荧光染色。结果 ICCs呈网络状分布于整个胃肠道,不同部位ICCs的分布及形态有所不同。在胃底部,仅见肌内ICCs(ICC-IM）,而在胃体和胃窦部除ICC-IM外,可见肌间ICCs(ICC-MY)分布在肌间神经丛周围;其细胞密度胃底ICC-IM最多,由胃底至胃窦逐渐减少,而ICC-MY由胃体至胃窦逐渐增多。在小肠可见ICC-IM, ICC-MY和深肌层ICCs(ICC-DMP)3个亚群,结肠管壁内也分布有ICC-IM、ICC-MY和黏膜下ICCs(ICC-SM)3个亚群。结论 沙鼠可用于有关ICCs正常形态、结构及功能的研究。     

促胰液素通过大鼠Cajal间质细胞促进胃平滑肌舒张

观察Cajal间质细胞(interstitial cells of Cajal，ICC)在胃平滑肌收缩的起搏作用，以及促胰液素对ICC促进胃平滑肌细胞舒张的影响。采用大鼠胃体上1/3起搏区及胃窦环行肌肌条以Kreb’s液恒温灌流，通过张力换能器输人生理记录仪记录胃肌条的机械运动。用美蓝加光照选择性损伤ICC，观察促胰液素对胃平滑肌舒张的作用。结果显示：(1)带有ICC的胃体起搏区和胃窦肌条记录到稳定的收缩活动，胃窦收缩频率和振幅较胃体起搏区高。(2)损伤胃环肌层ICC后，导致胃体起搏区和胃窦平滑肌收缩频率与振幅明显下降，运动几乎消失。(3)促胰液素0．06～0．5mg/L明显减少胃体起搏区和胃窦区的收缩频率和振幅，呈剂量依赖性减少。损伤ICC后几乎完全取消促胰液素促进胃肌的舒张作用。抗促胰液素血清和阿托品可阻断促胰液素的作用。     

2.117 Cajal间质细胞介导胃动素兴奋胃起搏区运动的作用

目的胃肠壁内的Cajal间质细胞(interstitial cells of Cajal,ICC)是胃肠慢波电位的启动者.本研究旨在观察大鼠ICC在胃起搏区收缩活动的特殊作用,以及兴奋性脑肠肽胃动素对ICC引起胃平滑肌细胞收缩活动的调节.方法采用大鼠胃体上1/3起搏区及胃窦环行肌3×10mm2肌条在95%O2,5 %CO2的恒温37℃灌流Kreb液中,通过张力换能器输入生理记录仪记录胃肌条的机械运动. 结果 1.带有ICC的胃肌正常自发收缩活动胃肌条孵育60min后出现稳定的收缩活动.胃体起搏区和胃窦收缩频率分别为3.9 2±0. 63次/min和4.14±0.50次/min.收缩振幅分别为0.25±0.05g和0.32±0.09g(均n=18) .胃窦收缩频率和振幅较胃体起搏区分别增高(5.61±0.84)%和(28.00±7.92)%.2.胃动素对带有ICC胃环行肌的作用胃动素0.0 3、0.06和0.12μg/mL明显增加胃体起搏区和胃窦的收缩频率和振幅,呈剂量依赖性增加 .在胃动素0.12μg/mL时,胃体起搏区比生理盐水对照组(NS)频率增加(30.84±6.52)% ,振幅增加(387.41±53.25)%.胃窦比NS组频率增加(14.62±3.71)%,振幅增加(135. 56±25.14)%(均P＜0.01,均n=18).结果显示,同剂量的胃动素对胃体起搏区的收缩作用比胃窦区强,两者差异显著(P＜0.01),表明胃体起搏区对胃动素较胃窦有较高的敏感性.3.破坏ICC对胃肌收缩活动的影响用化学药物美蓝(50μmol/L)+光照(50mW/cm2)破坏胃环肌层ICC细胞后,胃体起搏区平滑肌自发收缩频率和振幅急剧下降,分别比破坏ICC前下降(82.35±12.54)%和(85.41±1 4.37)%.而胃窦平滑肌的频率和振幅则分别下降(73.24±16.31)%和(75.82±11.33)%( 均P＜0.001,均n=18).结果显示胃体起搏区比胃窦区动力下降更明显,表明胃体起搏区平滑肌细胞更受ICC的控制.4.破坏ICC对胃动素增强胃动力的影响破坏环行肌ICC后几乎完全阻断胃动素对胃体起搏区和胃窦平滑肌的收缩作用.结论 ICC对胃平滑肌细胞的机械运动有直接的起搏作用,并通过脑肠肽胃动素进行化学调控,在胃体的起搏区其作用更为明显,证明胃体上1/3区域是胃运动的原动力部位.     

c-kit阳性细胞和胎儿食管平滑肌发育的关系

目的:探讨c-kit阳性细胞和α-平滑肌肌动蛋白阳性平滑肌细胞(α-SMA)在人胎儿食管中分布关系.方法:采用免疫荧光组织化学双重标记法对8例胎儿食管中c-kit阳性细胞和α-SMA阳性平滑肌细胞的分布进行观察.结果:c-kit阳性细胞在食管上段内肌层内侧有少量分布,肌间层和黏膜下层也可见零星分布,在食管中段外肌层开始有少量分布,内肌层数量中等,至食管下段内外肌层均有大量分布.α-SMA阳性平滑肌细胞在食管肌层由上至下逐渐增加,并由内肌层扩展到外肌层.在食管上端肌间层和黏膜下层可见少量c-kit和α-SMA共同表达.结论:c-kit阳性细胞可能是Cajal间质细胞,在胎儿食管的分布与平滑肌密切相关.食管内平滑肌细胞和Cajal间质细胞可能起源于同一种前体细胞.     

高糖条件下氧化应激-AMPK-Cx43-NLRP3途径调节大鼠胃平滑肌细胞外基质重构的机制研究

目的：探讨高糖条件下通过氧化应激-AMP活化蛋白激酶（AMPK）-缝隙连接蛋白43(Cx43)-核苷酸结合寡聚化结构域样受体蛋白3(NLRP3)通路对胃平滑肌细胞外基质重构的调节作用。方法：将体外培养的大鼠原代平滑肌细胞分为正常糖组、高糖组、高糖+NLRP3抑制剂MCC950(15 nmol/L)组、高糖+Cx43半通道阻滞剂GAP19(100μmol/L)组、高糖+AMPK抑制剂Compound C(CC; 10μmol/L)组和高糖+抗氧化剂α-硫辛酸（α-LA; 100μmol/L）组,均培养48 h后检测。Western blot检测细胞中caspase-1、基质金属蛋白酶2(MMP-2)、NLRP3、Cx43、转化生长因子β1(TGF-β1)、TGF-β3、金属蛋白酶组织抑制物1(TIMP-1)、嘌呤能P2X7受体（P2X7R）和磷酸化AMPK(pAMPK)蛋白水平;ELISA检测细胞培养液中腺苷三磷酸、白细胞介素1β、I型胶原（Col I）和Col Ⅲ含量。结果：与高糖组相比,高糖+MCC950组MMP-2和TGF-β3表达水平显著降低（P<0.01）,TGF-β1和...     

迷走神经与心房颤动犬上腔静脉肌袖内缝隙连接重构的关系

目的探讨心房颤动(AF)犬上腔静脉(SVC)肌袖缝隙连接蛋白(Cx)含量和分布改变与迷走神经的关系。方法24只杂种犬,分为3组:假手术组(Sham组)、切除上腔静脉-主动脉根部(SVC-AO)脂肪垫组(RM组)和保留SVC-AO脂肪垫组(RS组)。RM组和RS组植入起搏器起搏6周,以程序刺激或猝发刺激诱发建立AF犬模型;Sham组植入起搏器但不起搏。取SVC肌袖组织行Cx40、Cx43免疫荧光染色并定量分析,透射电镜观察缝隙连接(GJ)超微结构。结果RS组持续性AF诱发率为71.4%,高于RM组(P<0.01)。Sham组和RS组Cx40、Cx43表达高于RM组(P<0.05);RS组Cx40、Cx43表达高于Sham组(P<0.05)。Sham组和RM组Cx40、Cx43端/侧比值高于RS组(P<0.05)。RS组GJ通道变宽,出现肌溶解和线粒体空泡状改变。结论迷走神经可能通过介导SVC肌袖Cx重构而使AF易于发生和维持;切除SVC-AO脂肪垫可减弱此效应。     

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.