Substance P and its tachykinin NK1 receptor: a novel neuroprotective target for Parkinson's disease

Parkinson＇s disease （PD） is the most common motor neurode- generative disorder affecting approximately 4 million people worldwide. Although PD presents primarily with motor dysfunction, non-motor symptoms including cognitive decline, mood disorders, reduced olfaction and constipation are also of- ten present, with some of these non-motor symptoms even pre- senting prior to the onset of motor symptoms. It is well known that PD is largely caused by the gradual degeneration of dopa- minergic neurons within the substantia nigra pars compacta （SNc）, along with the presence of protein aggregates called Lewy bodies, which consist primarily of ct-synuclein and are found in the cytoplasm of surviving neurons. This ongoing cell loss and Lewy body pathology is not confined to the SNc, but is also seen in other brain regions implicated in PD pathogenesis such as the locus ceruleus.

Effect of nonpeptide NK1 receptor antagonist L-703,606 on the edema formation in rats at early stage after deep partial-thickness skin scalding

Objective:To investigate the effect and the relevant potential mechanism of nonpeptide neurokinin 1(NK1) receptor antagonist L-703,606 in the edema formation after burn injury. Method:1.-703,606 treatment was performed in Sprague-Dawley(SD) rats at early stage after deep partial-thickness skin scalding.One hundred and fifty two adult male SI) rats were used in the study and randomly divided into sham scald(SS,n=8),scald control(SC,n=48),and L-703,606 treatment(IT,n=48) groups.The rats in SC and LT groups were subjected to 20%total body surface area(TBSA) deep partial-thickness skin scalding.Modified Evans blue extravasation, tracing electron microscopy by lanthanum nitrate and mean water content assay were employed to observe and detect the changes of vascular permeability,ultrastructure and edema formation in adjacent tissue to the wounds and in the jejuna of rats at early stage(72 h) after scald.Results: The pathological increase of vascular permeability in the periwound tissue and jejunum of rats in LT group were significantly lower than that in SC group(P【0.01),and recuperated earlier. Meanwhile,the changes of water contents of corresponding tissues in LT group were lighter than those in SC group(P【0.01).The ultrastructural changes of the microvessels in the peri-wound tissue of LT group showed that the junctions between microvascular endothelium cells were more narrow than those of SC group,moreover,and the number of opening and the engorgement and cavitation of the vascular endothelium cells decreased,the areosis and edema in perivascular tissue lightened,and the precipitation of the high eletron density lanthanum tracing agent in the interspace of the tissue decreased significantly in LT group.Conclusions:It is concluded that nonpeptide NK1-receptor antagonist L-703,606 could lighten the vascular permeability and edema formation in the periwound tissue and jejunum,and accelerate the normalization process of pathological changes in the tissues of rats after scald.

Effect of gingerol on substance P and NK1 receptor expression in a vomiting model of mink

Background Gingerol is the generic term for pungent constituents in ginger, which has been reported to be effective for inhibiting vomiting. We attempted to investigate the antiemetic effect of gingerol and its effective mechanism on substance P and NK1 receptors in minks. Methods The antiemetic effect of gingerol was investigated during a 6-hour observation on a vomiting model in minks induced by cisplatin, （7.5 mg/kg, intraperitoneal）. The distribution of substance P and NK1 receptors in the area postrema and ileum were measured by immunohistochemistry, and the expression of NK1 receptor in the area postrema and ileum were measured by Western blotting. Results The frequency of cisplatin induced retching and vomiting was significantly reduced by pretreatment with gingerol in a dose-dependent manner （P 〈0.05）. Substance P-immunoreactive was mainly situated in the mucosa and submucosa of the ileum as well as in the neurons of the area postrema. The immunoreactive production of NK1 receptor was mainly situated in the muscular and submucosa of ileum and the neurons of area postrema, gingerol markedly suppressed the increased immunoreactivity of substance P and NK1 receptor induced by cisplatin in a dose-dependent manner （P 〈0.05）, and exhibited effective inhibition on the increased expression levels of NK1 receptor in both the ileum and area postrema dose-dependently （P 〈0.05）. Conclusions Gingerol has good activity against cisplatin-induced emesis in minks possibly by inhibiting central or peripheral increase of substance P and NK1 receptors.

Possible Mechanism of Action of Neurokinin-1 Receptors （NK1R） Antagonists

Recently, NK1R （Neurokinin-1 receptors） take attention as new and promising target in anticancer drug development area. It has been proved that non-peptide NK1R antagonists L-733,060, aprepitant and L-732,138 inhibited tumor growth in several cancer cell lines. For the development of novel NK1R antagonists as antitumor agents, heterocyclic compounds which were previously synthesized by our team, tested for their cytotoxic activities in several cancer cell lines in this study. Among the tested compounds, a benzothiazole derivative BSN-009 inhibited colon cancer cell lines growth by 57.53% by comparing the activity to the control drug aprepitant. Molecular modeling studies such as molecular docking and pharmacophore generation were performed with known NK1R antagonists and BSN-009 by using Discovery Studio 3.5 in order to explain their binding modes to NK1R. BSN-009 may be a good anticancer drug candidate as a possible NK1R antagonist and is worthy to carry on the anticancer studies.

慢性内脏高敏性大鼠结肠内P物质及其NK1受体表达的改变

目的 研究慢性应激刺激所致内脏高敏性大鼠和正常大鼠结肠内P物质 (substanup)及其NK1受体表达的改变 ,探讨内脏高敏感性产生的可能机制。方法 40只新生SD大鼠 ,随机分为 2组 :慢性应激模型组、正常对照组 ,每组 2 0只。模型组大鼠在出生后第 8天到 2 1天 ,每天接受结直肠扩张刺激 ;分别在第 8周、12周观察大鼠的腹部回缩反射 (AWR)和玻璃小球排出情况 ,进行肠道敏感性评估 :采用RT PCR方法检测二组大鼠结肠组织内P物质及其NK1受体mRNA的表达 ,并运用免疫组化SABC法观察NK1受体的分布。结果 模型组较正常对照组大鼠腹部收缩阈值明显降低 (P <0 .0 1) ,玻璃小球排出时间缩短 (P <0 .0 1) ;P物质及其NKl受体mRNA的表达明显增加 (P <0 .0 1) ,NK1受体免疫反应阳性产物显著浓密 ,以平滑肌层和黏膜层为著。结论 SP及其NK1受体表达增加在大鼠肠道高敏感性。

NK1受体非肽类拮抗剂L-703,606对严重烫伤大鼠早期P物质免疫反应阳性神经的影响

目的:探讨静脉给予NK1受体非肽类拮抗剂L-703,606后严重烫伤大鼠早期P物质免疫反应(SP-IR)阳性神经的变化规律。方法:将104只SD大鼠随机分为正常对照组(NC组,8只),烫伤对照组(SC组,48只),L-703,606组(LT组,48只)。SC组,LT组大鼠作20%TBSA深II度烫伤,应用免疫组化和计算机图像分析技术,动态观察经尾静脉给予NK1受体非肽类拮抗剂L-703,606(250 nmol/kg)后早期72 h创周和空肠SP-IR阳性神经形态及神经纤维平均光密度值的变化。结果:烫伤后72 h内,LT组SP-IR阳性神经的形态、神经纤维平均光密度值变化规律与SC组基本类似,但病理改变程度均较轻,恢复也较早。结论:NK1受体非肽类拮抗剂L-703,606能减轻严重烫伤大鼠早期SP-IR阳性神经纤维的病理改变,并能促进其恢复。

母婴分离大鼠脑一肠轴内P物质及其NK1受体的表达

目的研究P物质及其受体在新生期母婴分离大鼠模型脑-肠轴上的表达。方法将新生期Sprague-Dawley雄性大鼠随机分为两组：母婴分离组：在出生后第2~21天，使新生大鼠与哺乳期母鼠分离3h／d。对照组：在出生后第2~21天，不给予任何处理。成年后（出生后60d）给予结直肠球囊扩张（CRD），取远端结肠、腰骶段脊髓和中脑进行P物质和NKl受体免疫组化检测并定量分析。结果母婴分离组大鼠和对照组比较，结肠肌层P物质阳性面积百分数、结肠NKI受体阳性肌间神经丛数目、脊髓背角P物质阳性面积、脊髓背角NK1阳性分布积分、中脑导水管周围灰质（PAG）和中缝核（DR）内P物质阳性面积、中脑PAG和DR内NK1阳性分布积分差异均无统计学意义（P均〉0．05）。结论新生期母婴分离对P物质和NK1受体表达的影响不明显，P物质和NK1受体在母婴分离大鼠模型内脏感觉过敏发生机制中的作用可能不大。

脑梗死后抑郁大鼠脑内NK1受体表达变化的研究

目的:探讨P物质受体NK1与脑梗死后抑郁的关系。方法:健康雌性SD大鼠48只,随机分成4组:抑郁组(MD组)、大脑中动脉皮质支闭塞组(MCAO组)、梗死后抑郁组(PSD组)和正常对照组,模型制做成功后第4周和8周利用敞箱试验评估大鼠抑郁程度,平衡木试验评估大鼠神经功能缺损程度,间接免疫荧光法检测脑内NK1受体的表达。结果:MCAO组和PSD组术后平衡木评分较同期正常对照组和MD组低,4周基本恢复正常。PSD、MD组各时点敞箱垂直活动、水平活动评分较同期MCAO、正常对照组低,8周较4周进一步降低,但PSD和MD组间比较差异无显著意义。PSD和MCAO组大鼠术侧皮质均见梗死灶,未累及基底节区,4周见中风囊形成,8周部分大鼠患侧侧脑室扩张;MD组和正常对照组未见脑梗死灶。梗死后4周,MD组和PSD组NK1表达阳性细胞平均灰度值均较同期MCAO组和正常对照组增高,8周进一步增高(P<0.05),但两组间差异没有显著性;MCAO组4周较对照组增高,8周基本正常。结论:NK1受体高表达与梗死后抑郁有关,可能参与梗死后抑郁的发生发展过程。

NK1受体拮抗剂对早期烫伤微血管的保护作用

目的:NK1受体拮抗剂L-703,606对烫伤早期创周微血管超微结构的保护作用。方法:给予NK1受体拮抗剂L- 703,606后大鼠严重烫伤,硝酸镧示踪观察创周微血管的超微结构。结果:静脉给予L-703,606可使大鼠深Ⅱ度烫伤后早期创周微血管内皮细胞间连接明显变窄,开放减少,内皮细胞肿胀空化减轻,水肿减轻,镧示踪剂沉积减少;半定量分级评分显示差别有显著性意义。结论:静脉给予L-703,606可明显减轻深Ⅱ度烫伤大鼠后早期创周微血管结构及组织的病理性变化,拮抗水肿的发生。

NK1受体基因多态性与腹腔镜手术PONV的相关性分析

目的:探讨NK1受体基因多态性与妇科腹腔镜患者术后恶心呕吐(PONV)发生率的相关性。方法:选择80例择期全麻妇科腹腔镜手术患者,年龄18～65岁。术前采集外周静脉血5 mL,使用基因组DNA提取试剂盒抽取DNA,运用等位基因特异扩增法进行NK1受体基因分型,采用DNA测序仪直接测序对NK1受体的单核苷酸基因多态性进行分型。观察患者术后恶心呕吐发生频率和时间、恶心评分、疼痛评分、镇痛药物用量、止吐药的使用情况等。在本研究中呕吐和干呕均视为呕吐事件,并记录患者术中术后循环状态及其他不良反应的情况。结果:按照单核苷酸基因变异位点筛选出,野生型纯合子(wt/wt组)21例(26.3%),杂合子(wt/mut组)25例(31.3%),突变基因型纯合子(mut/mut组)34例(42.5%),mut/mut组6例发生PONV,发生率为17.6%,其发生率低于其他两组(P<0.05)。结论:NK1受体基因多态性与中国女性人群PONV发生率具有相关性,其中突变纯合子的PONV发生率较低。

NK1受体介导a,β-meATP外周注射导致急性疼痛的机制研究

目的在探讨P物质受体NK1在a,β-meATP外周注射引起外周伤害刺激引起疼痛的作用及作用机制。方法笔者采用P2X3受体特异性激动剂a,β-meATP给与大鼠足底注射建立伤害性急性疼痛模型。笔者给与大鼠射NK1受体选择性抑制剂S3144观察其对a,β-meATP足底注射引起伤害反应的影响。同时笔者采用免疫组化的方法观察大鼠背根神经节(DRG)上的NK1受体的表达的率以及S3144椎管内注射对其表达的影响。结果大鼠足底注射a,β-meATP 5分钟时出现显著的缩脚反应,而缩脚反应出现高峰的时间为注射后20分钟。而对照组足底注射生理盐水则缩脚次数不明显。两组缩脚次数有显著差异性P<0.05。椎管注射抑制剂TNP-ATP和S3144之后缩脚次数明显减少P<0.05。NKI受体在a,β-meATP足底注射在DRG神经元中小细胞上与足底注射生理盐水相比显著增加P<0.05,而椎管内注射S3144显著抑制NK1受体的表达。结论 NK1受体在DRG通过P2X3受体导致外周伤害性刺激引起的疼痛伤害性反应。

P物质/NK1受体对实验性胃溃疡大鼠胃肠动力的调节

目的:通过检测大鼠实验性胃溃疡愈合过程中胃肠功能及P物质(substance P,SP)表达改变,探讨SP/NK1受体(neurokinin1,NK1)通路对胃溃疡离体幽门平滑肌条收缩功能的影响及机制。方法:62只SD大鼠分为正常组(6只)、盐水对照组(24只)和溃疡组(32只)。采用常规冰乙酸腐蚀法制备大鼠乙酸性胃溃疡模型并测量溃疡面积;免疫组化染色观察SP的表达。甲基纤维素酚红溶液灌胃观察胃排空率和肠推进功能;张力换能器及多通道生理信号采集处理系统观察SP及NK1受体拮抗剂对离体胃幽门环形平滑肌条收缩反应性的影响。结果:溃疡组术后4 d形成呈典型的“环堤征”,10~14 d溃疡逐渐愈合,28 d溃疡处形成瘢痕组织。免疫组化结果显示:SP阳性细胞主要分布于黏膜胃底腺细胞、黏膜下层和肌层,溃疡4、10和14 d SP积分光密度值明显低于正常组和对照组(P<0.05,P<0.01)。溃疡组的胃排空率明显低于正常组和盐水组(P<0.05),盐水组胃排空率与正常组相比无统计学意义。幽门环形肌条收缩功能显示:溃疡组不同时相的肌肉收缩幅度与正常组相比均有不同程度降低(P<0.01);加入SP后,胃幽门环形肌收缩幅度增加,在加入NK1受体拮抗剂后,收缩幅度、收缩频率大幅度下降(P<0.05,P<0.01)。结论:胃溃疡时胃肠运动功能显著降低,其机制与SP/NK1受体信号通路受损有关。

纹状体NK1受体参与帕金森病异动症发生的实验研究

目的探讨神经激肽1（NKl）受体参与帕金森病（PD）运动并发症发生的具体分子机制，为治疗异动症（LID）提供新的方法及靶点。方法小鼠纹状体立体定向注射6-羟基多巴胺制作PD模型，4周后筛选成功的PD模型并随机分成5组：PD组、LID组、低中高不同浓度NK1受体拮抗剂组，并设有假手术组作为对照。低中高NK1受体拮抗剂组小鼠分别给予0．005、0．05和0．5mmol／LNKI受体拮抗剂处理，假手术组、PD组及LID组小鼠分别纹状体内注射等容积生理盐水作为对照。半小时后，LID组及不同剂量NKl受体拮抗剂组小鼠给予左旋多巴（15mg／kg）及苄丝肼（12mg／kg）腹腔注射。而假手术组及PD组小鼠腹腔注射生理盐水。观察各组小鼠异常不自主运动评分（AIM），Westernblot法检测各组小鼠纹状体中环磷腺苷调节的磷酸化蛋白-32（DARPP-32）、细胞外信号调节蛋白激酶1／2（ERKl／2）、N-甲基-D-天门冬氨酸受体1（NRl）和丝氨酸谷氨酸受体1（GluRl845）的磷酸化水平。结果中浓度NKl受体拮抗剂组总AIM评分低于LID组（P〈0．01），而低、高浓度NKl受体拮抗剂组与LID组之间差异无统计学意义。Westernblot结果显示PD组DARPP-32、ERKI／2、GluR1、NRl的磷酸化水平较假手术组明显降低（均P〈0．01）。LID组DARPP-32、ERK1／2、GluR1、NR1的磷酸化水平较PD组明显升高（均P〈0．01），而中浓度NKl受体拮抗剂组DARPP-32、ERKl／2、GluR1、NRl的磷酸化水平较LID组明显降低（均P〈0．05）。结论NKl受体拮抗剂可以减少PD小鼠LID的发生，突触后NKl受体参与了LID的发生。

Controlling Chemotherapy-Induced Nausea and Vomiting with Neurokinin-1 Receptor Antagonists in Patients on AC-Based Chemotherapy—Are We There Yet?

Chemotherapy-induced nausea and vomiting (CINV) are distressing side effects of chemotherapy. Neurokinin-1 receptor antagonists (NK1-RAs) have been incorporated in the contemporary management of CINV. However, clinical studies on NK1-RAs have shown mixed results in reducing CINV risk. Most studies focused on the use of aprepitant (APR) and casopitant (CAS) in breast cancer patients receiving AC-type (doxorubicin and cyclophosphamide) chemotherapy. In this study, we compared the study design and clinical efficacies of these NK1-RAs in reducing CINV risk. Among the selected eight studies, 4 APR Randomized Controlled Trials (RCTs), 2 APR Observational Studies (OSs) and 2 CAS RCTs were identified. Patient-related characteristics such as the proportion of females (60.0% - 100.0%), age (46.5 - 59.5 years), histories of motion (5.6% - 47.0% in NK1-RA arms) and morning sicknesses (14.2% - 45.0% in NK1-RA arms) and types of antiemetic regimens;as well as chemotherapy-related characteristics such as the proportion of patients on AC chemotherapy (15.0% - 100.0%) varied greatly. In terms of efficacies, both APR and CAS improved overall CR and vomiting in majority of the studies. None of the studies, however, demonstrated that NK1-RA could provide adequate nausea control. To conclude, NK1-RAs are effective in improving vomiting and overall CR, but not useful in controlling nausea or attaining CC, the ideal CINV endpoint. A shift in paradigm is needed for future CINV research. As healthcare providers continue to strive for optimum CINV control in their patients, we hope this review can help them make better informed clinical decisions.

奈妥匹坦帕洛诺司琼预防化疗引起的恶心呕吐:从临床试验到日常临床实践

化疗引起的恶心呕吐(CINV)是众多抗癌药物治疗中常见的不良事件,不仅会对患者生活质量带来负面影响,还有可能影响化疗效果。目前,指南建议的止吐方案可以预防大部分癌症患者的CINV。但临床医师并不能始终遵循指南建议,患者也常常难以坚持医师处方的治疗。因此需要采取一些提高指南依从性的方法。奈妥匹坦帕洛诺司琼(NEPA)是首个也是唯一一个固定剂量复方止吐药,由奈妥匹坦(口服)/福奈妥匹坦(静脉给药)与帕洛诺司琼(PALO)组成。NEPA可以联合地塞米松组成三联止吐方案,这是用于高致吐性化疗(HEC)患者和部分中致吐性化疗(MEC)患者预防CINV的推荐方案。因此,NEPA止吐治疗操作简单便捷,可能有助于提高指南依从性。本综述对CINV进行了概括,评价了在临床试验和真实实践中积累的NEPA止吐效果及安全性方面的证据,同时也评价了在关键临床试验之外的环境下,即日常临床环境中使用NEPA进行止吐的初步证据。此外,本文还评述了化疗期间使用NEPA控制恶心症状和提高患者生活质量,这是癌症患者管理中面临的两个大挑战。

NK-1抑制剂预防头颈部恶性肿瘤PF方案化疗相关恶心、呕吐的疗效观察

目的观察在头颈部恶性肿瘤PF方案(顺铂+5-氟尿嘧啶)化疗过程中应用NK-1抑制剂阿瑞匹坦(aprepitant)的止吐疗效及不良反应。方法 56例需行PF方案静脉化疗的头颈部恶性肿瘤患者,随机分为实验组及对照组,各28例。实验组患者接受NK-1抑制剂阿瑞匹坦+5-HT3受体拮抗剂格拉司琼+地塞米松的三药联合方案预防止吐,对照组接受5-HT3受体拮抗剂格拉司琼+地塞米松的两药联合方案预防止吐。1个化疗周期结束后评估两组患者的恶心、呕吐缓解情况及相关不良反应。结果 56例患者均按期完成化疗,在急性恶心、呕吐控制情况上,实验组均高于对照组,完全缓解率(CR)分别为57.1%vs 50.0%、50.0%vs 42.9%,有效率(RR)分别为82.1%vs 71.4%和78.6%vs 67.9%,差异无统计学意义(P>0.05)。在延迟性恶心、呕吐控制情况上,实验组与对照组完全缓解率CR分别为50.0%vs 21.4%、53.6%vs 25.0%,有效率(RR)分别为78.6%vs 46.4%、82.1%vs 53.6%,实验组明显高于对照组,差异有统计学意义(P<0.05)。两组患者主要不良反应均为轻度,差异无统计学意义(P>0.05)。结论本研究表明含NK-1抑制剂阿瑞匹坦的三药联合方案预防头颈部恶性肿瘤PF方案化疗引起的急性期及延迟期恶心、呕吐安全有效,可在临床进一步研究推广。

首个NK-1受体拮抗剂——阿瑞匹坦的概况介绍

化疗是肿瘤临床治疗中最常用的方法之一,化疗后恶心呕吐反应是影响化疗患者用药依从性和疗效的主要干扰因素之一。阿瑞匹坦是首个用于止吐的NK1受体拮抗剂,用于化疗中产生的急性或迟发性恶心和呕吐,本文对其作用机制、药动学、临床研究安全性等进行综述。

生姜对NK_1受体介导的豚鼠离体回肠收缩影响

目的 :观察生姜及其主要辛辣成分对NK_1受体介导的豚鼠离体肠管收缩的影响,从NK_1受体角度初步探讨生姜的止吐机制。方法:以豚鼠离体回肠为实验材料,利用恒温组织浴槽,在高中低三个浓度生姜汁(50μL、100μL、200μL)、6-姜酚(3×10-5mol·L^(-1)、1×10-5mol·L^(-1)、3×10-6mol·L^(-1))、6-姜烯酚(3×10-5mol·L^(-1)、1×10-5mol·L^(-1)、3×10-6mol·L^(-1))存在和不存在情况下,分别建立P物质(SP)和选择性NK_1受体激动剂GR73632的量效曲线,观察对肠管收缩和量效曲线的影响。结果:生姜汁、6-姜酚、6-姜烯酚均能剂量依赖性地抑制SP激发的离体肠管收缩增强,降低其平均张力(P<0.05,P<0.01或P<0.001);均可剂量依赖性地使SP的最大效应降低(P<0.001);除低浓度6-姜酚外,3个剂量的生姜汁、高中浓度的6-姜酚、3个浓度的6-姜烯酚对SP最大效应的抑制作用均显著强于SR140333(3×10-7mol·L^(-1)),与SR140333比较差异有统计学意义(P<0.001)。6-姜酚、6-姜烯酚均能剂量依赖性地抑制GR73632激发的离体肠管收缩增强,降低其平均张力(P<0.05或P<0.001);均可剂量依赖性地使GR73632的最大效应降低(P<0.001);高浓度6-姜酚和高浓度6-姜烯酚,对GR73632最大效应的抑制作用与阳性药SR140333(3×10-7mol·L^(-1))存在时比较均有增强趋势,但差异没有统计学意义(与SR140333比较,P>0.05)。生姜汁、6-姜酚、6-姜烯酚均可使SP的量效曲线非平行右移,并使最大效应显著降低;6-姜酚、6-姜烯酚均可使GR73632的量效曲线右移,并使最大效应显著降低。结论:生姜及其主要辛辣成分可以非竞争性阻断NK_1受体,这可能是生姜止吐作用的重要机制。

母婴分离致肠易激综合征大鼠模型的建立与评价

目的 研究新生期母婴分离导致肠易激综合征（IBS）大鼠模型的建立及其对P物质与其受体NK1表达的影响。方法将64只新生期雄性大鼠随机分为母婴分离组（在出生后第2～21天，每天将新生大鼠与哺乳期母鼠分离3h）和对照组（不给予上述处理）。成年后（出生后60d）两组大鼠均给予结直肠球囊扩张（CRD），用行为学观察和腹部回缩反射（AWR）评分来评估内脏痛反应，用免疫组化方法检测腰骶段脊髓背角P物质及其受体NK1的表达量，并进行远端结肠常规组织学检测。结果引起母婴分离组大鼠内脏痛反应的CRD压力阈值[（19．22±926）mmHg]显著低于对照组[（24．89±1091）mmHg]，差异有统计学意义（P〈0．05）。在40、60和80mmHg压力扩张下，母婴分离组的AWR评分均显著高于对照组（均P〈0．05）。CRD后母婴分离组腰骶段脊髓背角P物质及其受体NK1蛋白免疫反应阳性细胞数与对照组比较差异均无统计学意义（均P〉0.05）。母婴分离组和对照组大鼠在CRD前后结肠均未见组织损伤或炎症。结论新生期母婴分离能成功建立IBS大鼠模型，成年后在内脏刺激时产生过强的内脏痛反应和神经元活化反应，P物质及其受体NK1可能不参与其过程。

Bladder-colon chronic cross-sensitization involves neuro-glial pathways in male mice

BACKGROUND Irritable bowel syndrome and bladder pain syndrome often overlap and are both characterized by visceral hypersensitivity.Since pelvic organs share common sensory pathways,it is likely that those syndromes involve a cross-sensitization of the bladder and the colon.The precise pathophysiology remains poorly understood.AIM To develop a model of chronic bladder-colon cross-sensitization and to investigate the mechanisms involved.METHODS Chronic cross-organ visceral sensitization was obtained in C57BL/6 mice using ultrasound-guided intravesical injections of acetic acid under brief isoflurane anesthesia.Colorectal sensitivity was assessed in conscious mice by measuring intracolonic pressure during isobaric colorectal distensions.Myeloperoxidase,used as a marker of colorectal inflammation,was measured in the colon,and colorectal permeability was measured using chambers.c-Fos protein expression,used as a marker of neuronal activation,was assessed in the spinal cord(L6-S1 level)using immunohistochemistry.Green fluorescent protein on the fractalkine receptor-positive mice were used to identify and count microglia cells in the L6-S1 dorsal horn of the spinal cord.The expression of NK1 receptors and MAPK-p38 were quantified in the spinal cord using western blot.RESULTS Visceral hypersensitivity to colorectal distension was observed after the intravesical injection of acetic acid vs saline(P<0.0001).This effect started 1 h post-injection and lasted up to 7 d postinjection.No increased permeability or inflammation was shown in the bladder or colon 7 d postinjection.Visceral hypersensitivity was associated with the increased expression of c-Fos protein in the spinal cord(P<0.0001).In green fluorescent protein on the fractalkine receptor-positive mice,intravesical acetic acid injection resulted in an increased number of microglia cells in the L6-S1 dorsal horn of the spinal cord(P<0.0001).NK1 receptor and MAPK-p38 levels were increased in the spinal cord up to 7 d after injection(P=0.007 and 0.023 respectively).Colorectal sensitization was prevented by intrathecal or intracerebroventricular injections of minocycline,a microglia inhibitor,by intracerebroventricular injection of CP-99994 dihydrochloride,a NK1 antagonist,and by intracerebroventricular injection of SB203580,a MAPK-p38 inhibitor.CONCLUSION We describe a new model of cross-organ visceral sensitization between the bladder and the colon in mice.Intravesical injections of acetic acid induced a long-lasting colorectal hypersensitivity to distension,mediated by neuroglial interactions,MAPK-p38 phosphorylation and the NK1 receptor.