大鼠胃肠道5-羟色胺免疫活性内分泌细胞的分布及形态学观察

本文用肠卷石蜡切片的免疫组织化学反应(硫酸镍铵加强的PAP法)对5只大鼠胃肠道的5-羟色胺(5-HT)免疫活性内分泌细胞的分布及形态进行了研究。结果表明,大鼠胃肠道5-HT免疫活性内分泌细胞在胃幽门部、十二指肠和结肠的密度最高,在空肠、回肠、盲肠和直肠密度中等,在胃体部密度最低。5-HT免疫活性内分泌细胞的形状多样。有的细胞有几个突起穿行于其它上皮细胞之间;有的细胞的基底部有突起,突起的末端含有5-HT阳性物质;有时还见突起穿过基膜进入固有层内。多数细胞的5-HT阳性物质释放到腺腔面和肠腔面,说明EC细胞有内、外两种分泌方式释放5-HT。     

大鼠胃卵泡刺激素和促性腺激素释放激素受体的共定位

我们先前的研究已经研究,大鼠消化系统广泛分布有促性腺激素释放激素（GnRH）免疫反应性上皮细胞,而且证实这些细胞同样存在GnRH mRNA的杂交信号,说明胃、肠、胰腺能自身合成GnRH。随后我们又证实大鼠下颌下腺、胰腺和胃含有GnRH的受体,说明它们又是GnRH的靶器官。     

胃肠道间质肿瘤组织发生的探讨

目的探讨胃肠道间质肿瘤（ｇａｓｔｒｏｉｎｔｅｓｔｉｎａｌｓｔｒｏｍａｌｔｕｍｏｒ，ＧＩＳＴ）的组织发生。方法对３６例ＧＩＳＴ进行组织学、组织化学及免疫组织化学观察。结果胃和大肠间质肿瘤呈间叶细胞表型，但光镜下观察到在１５例发生于小肠的梭形细胞肿瘤中，瘤细胞之间存在着嗜酸性小体即丝团样纤维（ｓｋｅｉｎｏｉｄｆｉｂｅｒ，ＳＦ），Ｍａｓｓｏｎ三色染色呈蓝色，ＰＡＳ呈强阳性；免疫组化染色显示Ｓ－１００蛋白阳性率为４４．４４％，ｄｅｓｍｉｎ阳性率为８．３３％，瘤细胞的免疫表达与其分化程度无关。结论胃和大肠的间质肿瘤免疫表型复杂，提示其起源与原始间叶细胞有关，而小肠间质肿瘤大多数为神经源性肿瘤。可能起源于肠壁内在神经丛的神经膜细胞或来自小肠的自律神经。     

同时显示大鼠胃窦粘膜乙酰胆碱酯酶阳性神经和内分泌细胞的方法

本实验在同一张切片上利用Karnovsky-Roots(1964)方法,显示胃窦粘膜神经乙酰胆碱酯酶,用PAP免疫组织化学技术定位胃棗粘膜内分泌细胞(胃泌素细胞),为了解胃粘膜胆碱能神经和G细胞之间的形态关系,挺供一可行的方法。     

胰高血糖素样肽-2

胰高血糖素样肽GLP 1和GLP 2由小肠和大肠的内分泌细胞产生并分泌。GLP 2通过对胃的动力作用和营养吸收作用保持小肠粘膜上皮的完整 ,对小肠损伤修复等均有重要的调节作用 ,GLP 2在循环中二肽肽酶Ⅳ (DPIV)的作用下氨基末段迅速裂解失去活性 ,并通过肾脏清除。利用这些肽对营养吸收和能量平衡及在糖尿病动物模型和小肠疾病的作用 ,可供临床应用并治疗人类的疾病     

豚鼠肠粘膜下神经丛淋巴管旁神经元的烯醇化酶免疫组织化学观察

作者曾报道豚鼠肠粘膜下神经丛内,可能有一种特殊类型的淋巴管旁神经元。为了对上述的研究提供进一步的证据,本文应用显示神经元特异性烯醇化酶(NSE)的免疫组织化学方法,对这种类型的神经元进行了观察。胃肠神经丛内所有的神经元都呈NSE阳性反应,小肠和结肠粘膜下丛内的淋巴管旁神经元,也显同样的阳性反应。平滑肌和结缔组织细胞均为阴性。大多数淋巴管旁神经元具有典型的神经元形态特征;有些细胞虽不具有明显的神经元形态特点,但它们都显相同的NSE阳性反应。本文为我们前文报道的淋巴管旁神经元提供了更可信的证据。     

培养的大鼠胃平滑肌细胞GnRH受体的免疫组织化学及原位杂交研究

目的　观察培养的大鼠胃平滑肌细胞中是否能表达GnRH受体 ,为进一步研究GnRH对胃平滑肌细胞的功能提供形态学依据。　方法　采用免疫组织化学SABC和原位杂交方法。　结果　培养的大鼠胃平滑肌细胞呈GnRH受体免疫反应阳性 ,阳性物质分布于细胞浆和细胞膜上 ,细胞核呈阴性反应。培养的胃平滑肌细胞同样含有GnRH受体mRNA杂交信号 ,信号物质亦分布于细胞浆内 ,细胞核呈阴性反应。　结论　胃平滑肌细胞能自身表达GnRH受体 ,它可能也是GnRH的靶细胞     

鸡肠神经胶质细胞超微结构特征及钙结合蛋白S100β在小肠中的分布

目的观察10只健康黄羽肉鸡肠神经胶质细胞(EGCs)结构特征及钙结合蛋白S100β(S100β)蛋白在鸡小肠的分布特点,为探讨鸡肠神经胶质细胞的形态学特征提供实验依据。方法采用透射电子显微镜技术观察神经胶质细胞的超微结构特点,免疫组织化学SABC-AP法研究S100β蛋白的分布特征。结果电子显微镜下观察表明,鸡肠神经胶质细胞在小肠各段均呈星形,形态上属于星形胶质细胞,细胞核不规则,胞质中分布有大小不一的圆形或椭圆形无髓神经纤维。免疫组织化学显示,S100β在鸡小肠各段黏膜上皮细胞、肠腺表达较强,其中上皮细胞基膜和肠腺上皮细胞顶端为强阳性,固有膜为阴性,在黏膜下神经丛和肌间神经丛均呈强阳性表达。结论鸡肠神经胶质细胞属于星形胶质细胞,其在小肠的分布较为广泛,除具有营养、保护神经节细胞的功能外,可能还参与调节肠腺细胞分泌及黏膜免疫屏障功能。     

Down综合征16三体小鼠胃的神经发育观察

目的　研究Dow n 综合征动物模型16 三体和正常同窝鼠支配胃的神经发育。方法　采用16三体鼠培育,同窝鼠胚胎龄(em bryonic days, ED)13～18 天细胞遗传学分析,蛋白基因产物9.5(proteingene product 9.5, PGP9.5)免疫组化等方法对16 三体小鼠胃的神经发育进行了研究。结果　正常同窝鼠,胎龄13 天(ED13)来源于外胚层神经嵴的神经母细胞迁移并进驻胃壁;ED14 神经元发出突起,形成原始神经网络;ED15 形成简单排列的肌间神经丛,开始出现早期的神经节;ED16 有分布规则的肌间神经丛;ED17 神经母细胞进驻粘膜下层,形成粘膜下神经丛;ED18 完整的胃神经丛形成,即粘膜下浅、深神经丛和肌间神经丛。与正常同窝鼠比较,16 三体鼠胃神经系发育迟缓,ED14 胃壁始有散在分布神经元。此后,胃神经系的发育与分化均较正常延迟,至ED18 仅有肌间神经丛。根据胃神经系的发育程度和PGP9.5 免疫反应强度作半定量分析及秩和检验,16 三体鼠胃神经的发育明显落后于它们正常的同窝鼠,两者比较有显著性差异(P< 0.05)。结论　16 三体小鼠是公认的Dow n 综合征动物模型,它除了有多系统和多器官的畸型外,还发现有小鼠胃神经丛发育迟缓,粘膜下神经丛缺失。     

胎儿胃肠道胃泌素细胞与生长抑素细胞的免疫组织化学研究

本文用PAP免疫组织比学法和间接免疫荧光组织化学法,对60例8～38周胎儿胃肠粘膜中胃泌素细胞(G细胞)和生长抑素细胞(D细胞)的发生进行了研究。这两种细胞最早出现于8～9周胎儿十二指肠上皮中,但在固有膜及肌层未观察到。12周后,D细胞出现在胎儿胃肠全长粘膜,G细胞则只见于胃窦及小肠粘膜。本文还对各时期胎儿胃肠粘膜中D细胞和G细胞的分布、数量,以及二者比例变化等进行了观察。胃窦中G细胞与D细胞一样,基底部伸出突起,可能具有旁分泌功能。除胃底腺外,其余部位的D细胞和G细胞多为开放型细胞。本文对这两种细胞在胎儿胃肠发育中的可能功能进行了讨论,并与成人胃窦和十二指肠上部粘膜中G、D细胞的比例进行了对比观察。     

豚鼠胃和小肠5—羟色胺及其受体免疫组织化学双标记研究

实验用邻片免疫组织化学双标记法，对豚鼠胃和小肠５－羟色胺（５－ＨＴ）及５－ＨＴ受体进行双标记研究。结果显示，胃底腺壁细胞，小肠的绒毛上皮细胞和小肠腺上皮细胞均呈５－ＨＴ受体阳性，５－ＨＴ阳性内分泌细胞散在分布于５－ＨＴ受体阳性的细胞间，一些５－ＨＴ阳性的内分泌细胞同样呈５－ＨＴ受体阳性。胃及小肠肌层的平滑肌细胞呈５－ＨＴ阴性反应但呈５－ＨＴ受体阳性反应，肌间神经丛的神经纤维呈５－ＨＴ阳性，神经元胞     

促性腺激素释放激素类似物对大鼠胃肠道5-羟色胺分泌的影响

目的 研究GnRH对胃肠道内5-HT分泌的影响。方法胃腔直接注射GnRH类似物阿拉瑞林(A1arelin GnRH—A)以模拟外分泌产生的GnRH，并以免疫组织化学、高压液相色谱电化学检测(HPLC-ECD)的方法对阿拉瑞林刺激后胃及十二指肠内5-HT免疫反应细胞、血清中5-HT含量进行检测。结果 胃腔内注射GnRH—A后，大鼠胃及十二指肠内5-HT免疫反应阳性细胞密度显著增多，但血清中5-HT含量显著减少。结论 外分泌的OnRH对于5-HT的释放起明显抑制作用，但对5-HT的合成可能不产生影响。     

大鼠消化道促性腺激素释放激素受体的免疫组织化学研究

探讨大鼠消化道是否存在ＧｎＲＨ受体及其定位。方法采用兔抗ＧｎＲＨ抗独型抗体的免疫组织化学ＡＢＣ法。结果胃底腺壁细胞,胃小凹上皮细胞及肌间神经丛的副交感神经节细胞呈ＧｎＲＨ受体免疫反应性。     

Origins of synaptic inputs to calretinin immunoreactive neurons in the guinea-pig small intestine

Summary Calretinin immunoreactivity is almost completely confined to two classes of neuron in the myenteric plexus of the guinea-pig small intestine, longitudinal muscle motor neurons and ascending interneurons. Nerve cell bodies of the two classes can be readily identified by their sizes and positions in ganglia. The motor neurons, which are small Dogiel type I neurons, are about 20% and the interneurons, which are medium-sized Dogiel type I neurons, are about 5% of myenteric neurons. In the present work, we have also discovered a minor population (0.1%) of small filamentous neurons. In unoperated regions of intestine, at the light microscopic level, numerous calretinin immunoreactive nerve fibres were found in the tertiary plexus that innervates the longitudinal muscle and a medium density of varicose fibres formed pericellular endings in the myenteric ganglia. After double myotomy operations, in areas of plexus 0.5 to 1.5 mm wide which were isolated from ascending and descending inputs, calretinin-immunoreactive fibres of the tertiary plexus were unchanged, but the periceliular endings in the ganglia disappeared. Both the ascending interneurons and the longitudinal muscle motor neurons received ultrastructurally identified synapses and close axonal contacts that were calretinin-immunoreactive. These were counted in semi-serial sections from normal intestine and from regions between myotomy operations. In unoperated intestine, the proportions of calretinin-immunoreactive synapses on small, calretinin-immunoreactive, Dogiel type I nerve cells and small filamentous nerve cells were 30% and 0.1% respectively and on medium-sized Dogiel type I cells the proportion was 28%. Electron microscopy revealed an almost complete loss of immunoreactive inputs to the small Dogiel type I cells between double myotomies, but the number of unreactive inputs was the same as in normal intestine. This work demonstrates that the ascending calretinin-immunoreactive interneurons connect with one another to form ascending chains in the myenteric plexus and that they also provide about 1/3 of the inputs received by calretinin-immunoreactive longitudinal muscle motor neurons. Many of the remaining inputs to these motor neurons are local; we have deduced that these are mainly from primary sensory neurons.     

Neurons with 5-hydroxytryptamine-like immunoreactivity in the enteric nervous system: their visualization and reactions to drug treatment

Immunoreactive nerve cell bodies and fibres in the intestine have been examined using three antibody preparations raised against 5-hydroxytryptamine. Cross reactivity studies indicate that the substance localized was an hydroxylated indoleamine. In the guinea-pig small intestine, nerve cell bodies were located in the myenteric plexus and varicose fibres were found in the ganglia of the myenteric and submucous plexus. The nerve cell bodies had prominent short, broad processes and a single long process. Similar nerve cells and fibres were found in the guinea-pig stomach and large intestine and areas of intestine that were examined in mice, rabbits and rats. Properties of the neurons were examined in the small intestine of the guinea-pig. The immunoreactive material was depleted by treatment with reserpine, but not by guanethidine or 6-hydroxydopamine in dose sufficient to deplete noradrenaline stores in axons in the intestine. No depletion of 5-hydroxytryptamine by the neurotoxin 5, 7-dihydroxytryptamine was observed. After depletion by reserpine, immunoreactivity of the neurons could be restored by application in vitro of 5-hydroxytryptamine, 5,7-dihydroxytryptamine or 5-hydroxytryptophan. The restoration by 5-hydroxytryptophan was prevented by the inhibitor of L-aminoacid decarboxylase, benserazide. After reserpine treatment, immunoreactivity was not restored by tryptophan. Uptake of 5, 7-dihydroxytryptamine into the nerves was antagonized by fluoxetine. The distribution of neurons with 5-hydroxytryptamine-like immunoreactivity was compared with the distribution of enteric amine-handling neurons that take up and decarboxylate L-dopa. This comparison indicated that there are two classes of aromatic amine neuron in the guinea-pig small intestine, the enteric 5-HT neurons and enteric, non-5-HT, amine handling neurons.     

Immunohistochemistry for intermediate filaments in the enteric nervous system of the porcine small intestine.

Antibodies against the cytoskeletal neurofilament protein 200 and gliafilament acidic protein were used for an immunohistochemical staining of nerve and glia cells in porcine small intestine. In sections as well as in whole mount preparations, the morphological and topographical features of the enteric nerve plexus could be demonstrated. The enteric glia cells are characterized by an abundance of immunoreactive GFAP, which allows a subsequent staining of the plexus. NFP 200 is immunohistochemically recognized only in a part of the neurons. This immunoreactive neuronal population can be identified morphologically as Typ II-neurons, which are defined as adendritic and pseudouniaxonal to multiaxonal. The immunostaining of intermediate filaments is an easy and reproducible means for studying the enteric nervous system and invaluable for the histopathological diagnosis of its morphological abnormalities.