Serotonin receptor 2B induces visceral hyperalgesia in rat model and patients with diarrhea-predominant irritable bowel syndrome

BACKGROUND Serotonin receptor 2B(5-HT2B receptor)plays a critical role in many chronic pain conditions.The possible involvement of the 5-HT2B receptor in the altered gut sensation of irritable bowel syndrome with diarrhea(IBS-D)was investigated in the present study.AIM To investigate the possible involvement of 5-HT2B receptor in the altered gut sensation in rat model and patients with IBS-D.METHODS Rectosigmoid biopsies were collected from 18 patients with IBS-D and 10 patients with irritable bowel syndrome with constipation who fulfilled the Rome IV criteria and 15 healthy controls.The expression level of the 5-HT2B receptor in colon tissue was measured using an enzyme-linked immunosorbent assay and correlated with abdominal pain scores.The IBS-D rat model was induced by intracolonic instillation of acetic acid and wrap restraint.Alterations in visceral sensitivity and 5-HT2B receptor and transient receptor potential vanilloid type 1(TRPV1)expression were examined following 5-HT2B receptor antagonist adminis-tration.Changes in visceral sensitivity after administration of the TRPV1 antago-INTRODUCTION Irritable bowel syndrome(IBS)is a chronic functional bowel disorder characterized by recurrent abdominal pain with altered bowel habits that affects approximately 15%of the population worldwide[1].IBS significantly impacts the quality of life of patients.Although the pathogenesis of IBS is not completely understood,the role of abnormal visceral sensitivity in IBS has recently emerged[2,3].5-Hydroxytryptamine(5-HT)is known to play a key role in the physiological states of the gastrointestinal tract.Plasma 5-HT levels in IBS with diarrhea(IBS-D)patients were greater than those in healthy controls[4],suggesting a possible role of 5-HT in the pathogenesis of IBS-D.The serotonin receptor 2(5-HT2 receptor)family comprises three subtypes:5-HT2A,5-HT2B,and 5-HT2c.All 5-HT2 receptors exhibit 46%-50%overall sequence identity,and all of these receptors preferentially bind to Gq/11 to increase inositol phosphates and intracellular calcium mobilization[5].5-HT2B receptors are widely expressed throughout the gut,and experimental evidence suggests that the primary function of 5-HT2B receptors is to mediate contractile responses to 5-HT through its action on smooth muscle[6].The 5-HT2B receptor is localized to both neurons of the myenteric nerve plexus and smooth muscle in the human colon.The 5-HT2B receptor mediates 5-HT-evoked contraction of longitudinal smooth muscle[6].These findings suggest that the 5-HT2B receptor could play an important role in modulating colonic motility,which could affect sensory signaling in the gut.Other laboratories have shown that the 5-HT2B receptor participates in the development of mechanical and formalin-induced hyperalgesia[7,8].A 5-HT2B receptor antagonist reduced 2,4,6-trinitrobenzene sulfonic acid(TNBS)and stress-induced visceral hyperalgesia in rats[9,10].However,the role of the 5-HT2B receptor in IBS-D patients and in acetic acid-and wrap restraint-induced IBS-D rat models was not investigated.

Association of Serotonin Receptors with Attention Deficit Hyperactivity Disorder： A Systematic Review and Meta-analysis

Attention deficit hyperactivity disorder （ADHD） is one of the most common mental disorders in childhood, with a high heritability about 60% to 90%. Serotonin is a monoamine neurotransmitter. Numerous studies have reported the association between the serotonin receptor family （5-HTR） gene polymorphisms and ADHD, but the results are still controversial. In this study, we conducted a meta-analysis of the association between 5-HTRIB, 5-HTR2A, and 5-HTR2C genetic variants and ADHD. The results showed that the 861G allele of 5-HTRIB SNP rs6296 could significantly increase the risk of ADHD （OR= 1.09, 95% CI： 1.01-1.18）; the 5-HTR2C gene rs518147 （OR=1.69, 95% CI： 1.38-2.07） and rs3813929 （OR = 1.57, 95% CI： 1.25-1.97） were all associated with the risk of ADHD. In addition, we also carried on a case- control study to explore the relevance between potential candidate genes 5-HTR1A, 5-HTRIE, 5-HTR3A and ADHD. The results indicated that 5-HTRIA rs6295 genotype （CC＋CG vs. GG OR=Z00, 95% CI： 1.23-3.27） and allele （OR=1.77, 95% CI： 1.16-2.72） models were statistically significantly different between case group and control group. This study is the first comprehensive exploration and summary of the association between serotonin receptor family genetic variations and ADHD, and it also provides more evidence for the etiology of ADHD.

Alterations in serotonin, transient receptor potential channels and protease-activated receptors in rats with irritable bowel syndrome attenuated by Shugan decoction

AIM:To determine the molecular mechanisms of Shugan decoction(SGD) in the regulation of colonic motility and visceral hyperalgesia(VHL) in irritable bowel syndrome(IBS).METHODS:The chemical compounds contained in SGD were measured by high-performance liquid chromatography.A rat model of IBS was induced by chronic water avoidance stress(WAS).The number of fecal pellets was counted after WAS and the pain pressure threshold was measured by colorectal distension.Morphological changes in colonic mucosa were detected by hematoxylin-eosin staining.The contents of tumor necrosis factor(TNF)-αin colonic tissue and calcitonin-gene-related peptide(CGRP)in serum were measured by ELISA.The protein expression of serotonin[5-hydroxytryptamide(5-HT)],serotonin transporter(SERT),chromogranin A(Cg A)and CGRP incolon tissue was measured by immunohistochemistry.RESULTS:SGD inhibited colonic motility dysfunction and VHL in rats with IBS.Blockers of transient receptor potential(TRP)vanilloid 1(TRPV1)(Ruthenium Red)and TRP ankyrin-1(TRPA1)(HC-030031)and activator of protease-activated receptor(PAR)4 increased the pain pressure threshold,whereas activators of PAR2and TRPV4 decreased the pain pressure threshold in rats with IBS.The effect of SGD on pain pressure threshold in these rats was abolished by activators of TRPV1(capsaicin),TRPV4(RN1747),TRPA1(Polygodial)and PAR2(AC55541).In addition,CGRP levels in serum and colonic tissue were both increased in these rats.TNF-αlevel in colonic tissue was also significantly upregulated.However,the levels of 5-HT,SERT and Cg A in colonic tissue were decreased.All these pathological changes in rats with IBS were attenuated by SGD.CONCLUSION:SGD alleviated VHL and attenuated colon motility in IBS,partly by regulating TRPV1,TRPV4,TRPA1,PAR2,5-HT,Cg A and SERT,and reducing CGRP and TNF-αlevel.

Serotonin 2C Receptor Alternative Splicing in a Rat Model of Orofacial Neuropathic Pain

Abnormal serotonin 2C receptor (5HTR2C) alternative splicing and RNA editing are involved in the etiology of pain disorders. Functional 5HTR2C can only be generated when alternative exon Vb is included within the mRNA;the small nucleolar RNA RBII-52 is complementary to exon Vb and promotes its inclusion. The expression of HBII-52 (the human equivalent of RBII-52) is reduced in Prader-Willi syndrome, patients of which have a high pain threshold. Here, we measured the pain threshold in a rat model of orofacial neuropathic pain and related it to the expression levels of wild-type and variant 5HTR2C and RBII-52. We generated an infraorbital nerve loose ligation model of neuropathic pain in rats and measured the pain threshold of the animals using mechanical stimulation with von Frey filaments. We then sacrificed the animals and examined the RNA levels of 5HTR2C and RBII-52 in the cervical spinal cord by real-time PCR. On post-injury day 28, pain threshold values in injured rats were significantly lower than in sham-operated or na?ve animals. The levels of total and exon Vb-skipped 5HTR2C mRNA were significantly lower in injured rats than in that sham-operated or na?ve rats, and the ratio of exon Vb-skipped 5HTR2C to total 5HTR2C was significantly higher. There were no significant differences in RBII-52 expression among the groups. Our data suggest that neuropathic pain induces serotonergic dysfunction mediated by 5HTR2C alternative splicing. 5HTR2C might be subject to complicated and fine regulation both by RNA editing and by alternative splicing.

Effects of Activation and Blockade of Serotonin 5-HT1A Receptors on the Immune Response in Rats Selected for Different Levels of Aggressiveness

The present study examines the effects of serotonin (5-HT) 1A receptor ligands on humoral im-mune response in two rat lines selected for over 75 generations for the enhancement or elimination of aggression. Activation of presynaptic 5-HT1A receptors with a low dose of the selective 5-HT1A receptor agonist 8-OH-DPAT (0.1 mg/kg) or the blockade of postsynaptic 5-HT1A receptors with the antagonist WAY-100635 (1.0 mg/kg) did not affect the numbers of IgM-antibody forming cells (IgM-AFC) in the spleen of highly aggressive rats, which were characterized by higher immune responsiveness compared to nonaggressive line. On the other hand, the same doses of 8-OH-DPAT and WAY-100635, as well as a higher dose of 8-OH-DPAT (1.0 mg/kg), which is known to activate postsynaptic 5-HT1A receptors, produce immunostimulation in nonaggressive rats. However, only the highest dose of 8-OH-DPAT (5.0 mg/kg) was able to cause immunosuppression in nonaggressive rats that was mainly dependent on stimulation of postsynaptic 5-HT1A receptors. In contrast to nonaggressive rats, the dose of 1.0 mg/kg 8-OH-DPAT was sufficient to produce a decrease in the numbers of IgM-AFC in highly aggressive rats. Thus, pharmacological activation of pre- and postsynaptic 5-HT1A receptors, as well as the blockade of postsynaptic 5-HT1A receptors, produced different effects on the immune response in two lines of rats selected for high level of aggression or its absence. These data may have implications for more efficient treatments of a number of mental disorders associated with abnormal aggression.

酸枣仁提取物调控miR-7b-3p/5-羟色胺1A受体表达促进骨生长

背景:前期研究发现,酸枣仁提取物通过提高脑组织5-羟色胺1A受体(serotonin 1A receptor,5-HT1AR)表达,使之与5-羟色胺结合,延长小鼠慢波睡眠,促进生长激素的分泌,从而使骨生长。5-HT1AR作为一种蛋白质,其表达丰度受到miRNA的调控。作者推测酸枣仁提取物可能通过miRNA调控5-HT1AR的表达从而发挥药物作用。目的:观察酸枣仁提取物通过干预小鼠脑组织中miR-7b-3p/5-HT1AR通路对骨骼生长的影响。方法:①将昆明种小鼠分为正常对照组、用药组(灌胃酸枣仁提取物0.320 mg/g),阳性对照组(灌胃酸枣仁皂甙0.013 mg/g)和酸枣仁提取物+5-HT1AR抑制剂组(灌胃酸枣仁提取物最后3 d同时每天侧脑室注射5-HT1AR选择性抑制剂P-MPPF 8μg),25 d后观察酸枣仁提取物对小鼠骨生长、血清生长激素水平及脑组织5-HT1AR表达的影响;②基因芯片法筛选由酸枣仁提取物引起的骨生长小鼠与普通小鼠脑组织差异表达的miRNAs,并通过PCR验证和双荧光素酶报告基因实验证实筛选的miR-7b-3p与5-HT1AR的调控关系;③体外培养小鼠脑皮质细胞并鉴定,利用Western blot法观察酸枣仁提取物对脑皮质细胞中5-HT1AR表达的影响;④将昆明种小鼠分为正常对照组、用药组、miR-7b-3p inhibitor组、用药+miR-7b-3p mimics组、阳性对照组,观察各组小鼠脑组织5-HT1AR表达及5-羟色胺与5-HT1AR结合活性;⑤将SD大鼠分为正常对照组、用药组、miR-7b-3p inhibitor组、用药+miR-7b-3p mimics组、阳性对照组,观察各组大鼠慢波睡眠的变化。结果与结论:①酸枣仁提取物可以促进小鼠体长、胫骨增长,促进生长激素分泌,提高脑组织5-HT1AR含量;②基因芯片筛选出差异表达的miRNAs个数为16个,其中上调有13个,下调有3个;生物信息学预测下调miR-7b-3p可以调控5-HT1AR表达,且双荧光素酶报告基因实验证实二者有直接调控关系;③酸枣仁提取物和沉默脑皮质细胞中miR-7b-3p表达可以引起5-HT1AR高表达;沉默miR-7b-3p后小鼠脑组织5-HT1AR表达、5-羟色胺与5-HT1AR结合活性及生长激素分泌均升高;过表达miR-7b-3p后小鼠脑组织5-HT1AR表达、5-羟色胺与5-HT1AR结合活性及生长激素分泌均降低;大鼠慢波睡眠期也相应延长或缩短。结果表明,酸枣仁提取物能够降低脑组织的miR-7b-3p水平,同时增加5-HT1AR的表达量。这种机制有助于延长慢波睡眠周期,并且促进生长激素的生成,对骨骼生长有积极影响,为使用酸枣仁提取物作为促进骨骼生长的潜在手段提供了科学依据。

Effects of Estradiol on 5-HTsA and 5-HT2c Receptor Immunolabeling in Rat Hippocampus

Steroid hormones participate in the modulation of serotonergic transmission, including the regulation of synthetic and metabolic enzyme production, as well as receptor and transporter activity. The changes of 5-HT5A and 5-HT2c immunolabeling induced by steroids in the hippocampus ofovariectomized rats were studied in this work. Densitometric analysis in rat hippocampi were carried out for adjacent brain coronal immunolabeled sections after treatment with subcutaneous injections of vehicle, estradiol, progesterone or the combination of both steroids in ovariectomized rats. Exposure to estradiol and the combination of estradiol and progesterone significantly reduced the 5-HT5A-like immunosignal in the CA 1 region while progesterone did not induce changes. On the other hand, exposure to the combination of estradiol and progesterone or estradiol alone increased the 5-HT2c immunosignal in the same region. These results indicate that estradiol is involved in the discrete regulation of serotonin receptors 5-HT5A and 5-HT2c in rat hippocampus.

Heat-Killed <i>Lactobacillus brevis</i>SBC8803 Induces Serotonin Release from Intestinal Cells

Previously, we reported that changes induced in autonomic neurotransmission in rats by Lactobacillus brevis SBC8803 may be mediated by serotonin 3 (5-HT3) receptors. In this study, we evaluated the effects of heat-killed L. brevis SBC8803 on serotonin (5-HT) releasing from intestinal cells. In the in vitro study, L. brevis SBC8803 stimulated 5-HT release from cultured rat endocrine RIN-14B cells (SBC8803 vs. sterile water;P in vivo study, 2 mg of heat-killed L. brevis SBC8803 was administered using a stomach sonde (feeding needle) to C57BL/6J mice. Analysis of plasma by ELISA showed gradually increase in 5-HT concentrations (0 min vs. 60 min;P ex vivo cultured intestinal loops composed of duodenum and part of the jejunum, from C3H/HeN and C57BL/6J male mice indicated that L. brevis SBC8803 effectively induced 5-HT release (SBC8803 vs. sterile water;P L. brevis SBC8803 may stimulate 5-HT release from mouse intestinal cells such as enterochromaffin cells.

Role of 5-HT2A Receptors in Immunomodulation in Animal Models of Aggressive Behavior

Serotonin 5-HT2A receptors are playing an important role in the pathophysiology of aggressive behaviors and in the control of immune function. In the present study, we analyzed the effects of activation and blockade of 5-HT2A receptors with selective ligands on the immune response formation in animals with aggressive behaviors induced by genetic factors (rats selected for the increased aggressiveness toward human) or by chronic social stress (mice of the CBA/Lac strain engaged in 10 days of social confrontations). Activation of 5-HT2A receptors with DOI at 1.0 mg/kg reduced the immune response level both in aggressive rats and mice compared to the corresponding vehicle-treated groups, while DOI administration did not alter the immune reaction in nonaggressive animals. The blockade of 5-HT2A receptors with ketanserin at 1.0 mg/kg resulted in immunostimulation both in mice of the CBA strain not subjected to social stress (the controls) and in nonaggressive rats selected for elimination of aggressiveness. On the other hand, its administration to CBA mice demonstrating offensive aggression enhanced the immune reaction, while the same dose of ketanserin did not modify the immune response level in rats with genetic predisposition to the increased defensive aggression. Thus, our data suggest that the role of 5-HT2A receptors in immunomodulation depends on the specific type of aggression that may be taking into account in the treatment of some neuropsychiatric disorders with the antipsychotic drugs and antidepressants targeting 5-HT2A receptors.

磁共振成像在体可视化检测肾脏5-羟色胺的动态变化及药物性急性肾损伤早期无创诊断

【目的】磁共振成像(MRI)在体检测肾脏5-羟色胺受体的动态变化,为药物性急性肾损伤早期诊断提供无创影像方法。【方法】以5-羟色胺基团为基础,构建具有5-羟色胺受体靶向性的磁共振对比剂(HT-Gd),通过检测小鼠肾脏部位T1加权磁共振成像(T1WI)信号,探索药物性肾损伤早期MRI检测方法。【结果】体外细胞内吞试验发现,经顺铂预处理12 h后,肾小管上皮细胞(HK-2)对HT-Gd的摄取是36.8 pg/cell,而未经顺铂处理细胞对HT-Gd摄取量仅为14.7 pg/cell。在体内磁共振成像研究中发现,HT-Gd可以增强顺铂给药24 h小鼠的肾脏T1WI信噪比至40.5%,约为未经顺铂处理组小鼠的2倍(SNR=20.2%)。【结论】HT-Gd可视化检测肾脏部位的5-羟色胺受体,实现了对顺铂诱导急性肾损伤的早期诊断,为药物性急性肾损伤早期诊疗研究提供了新的参考方法。

抑郁症单胺类递质受体研究进展

目前认为 ,抑郁症的发病主要与单胺类递质有关。单胺类递质受体系统在抑郁症的发病及治疗过程中会发生明显变化。本文综述了 5 羟色胺受体。

5-羟色胺与创伤后应激障碍的研究进展

创伤后应激障碍(posttraumatic stress disorder,PTSD)是当机体遭受威胁生命或者强烈精神创伤后发生的疾病。近年来研究发现,5-羟色胺(5-HT)可能通过5-羟色胺转运体 (SERT)、5-HT受体(主要包括5-HT 1A 、5-HT1B、5-HT2A和5- HT2C受体),以及多巴胺、去甲肾上腺素等神经递质相互作用,参与PTSD的发生,该文就此进行综述。

慢传输型便秘患者结肠中五羟色胺受体亚型的表达及意义

目的:研究主要5-HT受体亚型在慢传输型便秘(slowtransitconstipation,STC)患者结肠中的表达,探讨其在慢传输型便秘发病机制中的作用.方法:采用免疫组化EnVision法,检测20例STC患者和20例对照组结肠组织中5-HT1A,5-HT3和5-HT4受体的分布及表达水平,并采用IMS计算机辅助图像分析系统进行半定量分析.结果:5-H1A受体分布于黏膜下层、肌层,肌间神经丛5-HT1A受体的表达在STC组和对照组间无显著差异(P=0.548).5-HT3受体分布于黏膜下层和肌层,肌间神经丛STC组阳性指数显著低于对照组(65.2±15.9vs94.3±20.1,P<0.01).5-HT4受体分布于黏膜层、黏膜下层、肌层.在黏膜层和肌间神经丛,STC组5-HT4受体阳性指数均显著低于对照组(57.8±10.9vs78.5±12.9,P<0.01;77.5±19.9,119.2±26.9,P<0.01).STC组中,5-HT3受体表达水平与结肠传输试验第5天体内残留标志物数量无关(P>0.05);但5-HT4受体表达水平与第5天体内残留标志物数量呈负相关(r=-0.782,P<0.01).结论:STC患者结肠中存在5-HT3和5-HT4受体亚型的表达下调,两者可能参与了STC的发病机制.

抑郁症模型大鼠血清雌激素水平与海马5-HT含量之间的关系

目的:观察抑郁症模型大鼠血清雌二醇(E2)水平、海马5-羟色胺(5-HT)含量及其中缝核雌激素受体β(ERβ)和色氨酸羟化酶2(TPH2)表达的变化,探讨抑郁症发生的可能机制。方法:雌性SD大鼠20只,随机平均分为正常组和模型组,模型组给予孤养和21d慢性不可预见性的温和应激(CUMS)制备抑郁症大鼠模型。采用放射免疫分析法(RIA)测定血清雌二醇(E2)水平、高效液相色谱-电化学检测法(HPLC-ECD)测定海马5-羟色胺(5-HT)含量、RT-PCR技术检测中缝核ERβmRNA和TPH2mRNA表达以及荧光免疫组化双重染色法检测中缝核ERβ蛋白和TPH2蛋白表达。结果:21d应激后,模型组大鼠血清E2水平下降、海马5-HT含量减少、中缝核ERβmRNA和TPH2mRNA相对表达量下降及ERβ阳性细胞数和TPH2阳性细胞数明显减少。结论:E2与海马5-HT之间可能存在E2→中缝核5-HT能神经元ERβ→TPH2→海马5-HT的功能作用链。

大鼠脊髓和后根节内5-HT_(1A,2A)受体mRNA阳性神经元的分布

目的 观察大鼠脊髓及后根节内 5 - HT1 A,2 A受体 m RNA阳性神经元的分布。 方法 原位杂交组织化学技术。 结果 (1) 5 - HT1 A受体 m RNA阳性神经元分布于脊髓灰质各层 ,主要见于后角浅层 ( 、 层 )及 、 层 , ～ 层和 层也有散在分布。前角 ( 层 )内仅有少量阳性神经元 ;(2 ) 5 - HT2 A受体 m RNA阳性神经元的分布较局限 ,主要见于后角浅层及前角 ( 层 )神经元 ,在其他各层仅呈散在分布。在大鼠后根节内观察到 :(1) 10 .4%的后根节细胞呈 5 - HT1 A受体 m RNA阳性 ,阳性细胞以中、小型节细胞为主 ;(2 ) 17.4%的后根节细胞呈 5 - HT2 A受体m RNA阳性 ,阳性细胞也以中、小型节细胞为主。 结论 5 - HT1 A和 5 - HT2 A受体在脊髓和后根节内具有不同的分布特点 ,它们在介导 5 -羟色胺在脊髓水平的镇痛及在外周的致痛作用中可能扮演着重要的角色。

5-HT_1受体各亚型mRNAs在大鼠脊髓不同节段背角和腹角的表达(英文)

为进一步了解5-HT受体在中枢感觉和运动机能中的作用,本研究利用反转录PCR方法比较了5-HT1A,5-HT1B,5-HT1D,5-HT1E和5-HT1F受体亚型mRNAs在脊髓不同节段的背角、腹角的表达。结果显示:5-HT1A,5-HT1B,5-HT1D受体亚型mRNA的表达水平在胸、腰、骶段脊髓的背角明显高于腹角;而颈段背角内的表达仅略高于腹角。脊髓内未检测到5-HT1E受体亚型;5-HT1F受体亚型在脊髓各节段的背角和腹角都有较高水平的表达。5-HT1受体家族各亚型mRNA在脊髓背角和腹角表达水平的差异可能提示它们在中枢感觉和运动功能中发挥不同的作用。

何首乌提取物对血管性痴呆大鼠5-HT受体及生化指标的影响

目的研究何首乌提取物对血管性痴呆大鼠学习记忆的影响,初步探讨血管性痴呆大鼠5-HT2A受体的表达及血清超氧化物歧化酶(SOD)活性、丙二醛(MDA)含量的变化。方法采用双侧颈总动脉永久性结扎法建立大鼠血管性痴呆模型,随机分为假手术组、模型组、阳性对照组、何首乌组。通过水迷宫实验检测各组大鼠的学习记忆能力和血清SOD活性、MDA含量的变化;通过免疫组化技术检测各组大鼠丘脑前核内5-HT2A受体的表达水平。结果模型组大鼠d4逃避潜伏期(38.95±27.42)s,平台象限游泳时间(20.35±3.52)s,穿过平台次数(1.50±0.76),SOD活性(0.855±0.094)kU/g prot,MDA含量(5.187±1.237)μmol/g prot,5-HT2A受体的阳性细胞积分光密度值增高。何首乌组大鼠d4逃避潜伏期(15.28±9.83)s,平台象限游泳时间(24.66±3.56)s,穿过平台次数2.75±1.28,SOD活性(0.968±0.158)kU/g prot,MDA含量(4.595±1.104)μmol/g prot,5-HT2A受体的阳性细胞积分光密度值降低。其机制与何首乌组与模型组差异显著(P<0.05),假手术组、阳性对照组与何首乌组差异不显著。结论何首乌提取物能够改善血管性痴呆大鼠学习记忆功能,其机制与使5-HT2A受体表达增强以及抗氧化损伤有关。

腹泻型肠易激综合征患者结肠黏膜5-羟色胺和5-羟色胺_3受体的研究

背景:肠易激综合征(IBS)是一种功能性胃肠道疾病,其病因和发病机制迄今尚未完全阐明。目的:探讨5-羟色胺(5-HT)和5-HT3受体(5-HT3R)在腹泻型IBS(D-IBS)患者结肠黏膜中的变化及其临床意义。方法:对18名正常人和28例D-IBS患者行结肠镜检查并分别取升结肠、横结肠、降结肠和乙状结肠黏膜标本各两块。以免疫组化方法检测5-HT阳性细胞;以蛋白质印迹分析半定量检测5-HT3R的表达。结果:D-IBS组4个部位结肠黏膜的5-HT阳性细胞数和5-HT3R的表达均较正常对照组显著增多(P<0.05),但4个部位之间相互比较均无显著差异。结论:D-IBS患者结肠黏膜5-HT合成和分泌增多,5-HT3R表达上调,提示5-HT和5-HT3R可能为D-IBS的分子生物学基础之一,为D-IBS的治疗提供了分子靶点。

5─羟色胺在四季鹅抱窝中的作用

对５─羟色胺（５—ＨＴ）在四季鹅抱窝中的作用进行了研究．口服５－ＨＴ受体阻断剂，可使抱窝四季鹅的血液催乳素（ＰＲＬ）、β－内啡吠（β－ＥＮＤ）水平迅速下降，抱窝持续时间由２９．２０±１．５６ｄ缩短至４．２０±１．５８ｄ．结果表明：５—ＨＴ参与四季鹅ＰＲＬ和β─ＥＮＤ的调节，在抱窝机理中起着重要作用．β─ＥＮＤ在抱窝中的作用仍需进一步深入研究．

大鼠神经系统内5-羟色胺2A受体亚型的免疫组织化学定位(英文)

目的 观察大鼠神经系统内 5 羟色胺受体 2A亚型 (5 HT2AR)免疫组织化学染色阳性结构的分布。 方法 5 HT2AR特异性抗体的免疫组织化学染色。 结果 5 HT2AR阳性胞体主要分布于嗅球的小球层和僧帽细胞层、海马始层、外侧缰核、丘脑背外侧核、下丘脑室旁核、中脑中央灰质、小脑浦肯野细胞、脑干运动核和感觉神经节等 ;5 HT2AR阳性纤维和终末主要分面于嗅球的小球层和内丛层、大脑皮质、外侧隔核、杏仁外侧核、丘脑网状核、腹侧顶盖区、桥核、下橄榄及脑干运动核等。 结论 5 HT2AR亚型阳性结构广泛分布于大鼠神经系统 ,它们可能介导 5 HT在神经系统中的多种生理功能。