枕纹锦蛇消化道5-羟色胺免疫活性内分泌细胞的分布与形态学观察

采用ABC免疫组织化学法,应用5—羟色胺(5-HT)特异性抗血清,对枕纹锦蛇(Elaphe dione)消化道内含有的5—HT内分泌细胞进行了免疫组织化学的定位研究和形态学观察。结果显示,5-HT细胞在消化道各部位的分布密度呈倒“V”形,以十二指肠最高,胃贲门部最低。其形态多样,上段(食管、胃)多为圆形和椭圆形,主要分布于上皮基部和腺泡上皮之间;中段(十二指肠、空肠、回肠)以细长锥体形、梭形、圆形为主,主要分布于上皮基部和上皮细胞之间;下段(直肠)为圆形,分布于上皮基部。锥体形细胞常有一个长突起伸入到固有膜或肠腔,行使内或外分泌功能;梭形细胞有两个细长突起,一个指向固有膜,另一个指向肠腔,表明这种细胞可能具有内、外分泌的双重功能。     

40周HBK-SPF鸭胃肠道5-羟色胺细胞的免疫组织化学定位

目的应用5-HT抗血清研究40周HBK-SPF鸭胃肠道内的5-HT免疫活性细胞的分布密度及形态,并探讨其分布型的成因及细胞形态与功能的关系。方法免疫组织化学ABC法。结果5-HT细胞主要分布于十二指肠及其以下部位,腺胃偶见,分布密度近似呈波浪形,其中以直肠分布密度最高,小肠呈U形分布。5-HT细胞的形态多样,呈圆形、椭圆形、锥体形等,主要分布于胃肠粘膜上皮之间、上皮基部、固有膜以及腺泡上皮之间等。结论40周HBK—SPF鸭5-HT细胞分布型的形成与各部位消化功能有关;根据其形态,我们认为40周HBK—SPF鸭胃肠道内5-HT细胞具有内、外分泌两种功能。     

中华花龟消化道5-羟色胺免疫活性内分泌细胞的分布与形态学观察

应用5-HT抗血清,以ABC（avidin-biotin-peroxidase complex）免疫组织化学方法,探究中华花龟消化道内5-HT免疫反应阳性内分泌细胞的分布及形态。结果表明,5-HT阳性细胞从食管到直肠的消化道各段均有分布,以十二指肠部位分布密度为最高,胃幽门部次之,食管部最低;5-HT阳性细胞广泛分布于上皮细胞之间、上皮基部、腺泡上皮细胞之间、腺泡之间以及固有膜内,形态多样呈圆形、椭圆形、锥体形、梭形等,以锥体形为主。认为中华花龟消化道5-HT阳性细胞具有内、外分泌两种作用途径,并且5-HT阳性细胞的密度分布可能与其食性、生活环境等有关。     

蛇岛蝮蛇消化道5-羟色胺细胞的形态与分布

采用ABC(avidin-biotin-peroxidase complex)免疫组织化学方法,观察蛇岛蝮蛇(Gloydius shedaoensis)消化道内5-羟色胺(5-HT)免疫阳性内分泌细胞的分布及形态.结果显示,5-羟色胺细胞从食管到直肠各段均有分布.细胞分布密度呈波浪式,其中胃贲门部分布密度最高(7.15±2.38),直肠部次之(4.55±3.14),食管部最低(1.2±0.71).5-HT阳性细胞广泛分布于消化道上皮细胞之间、上皮基部、腺泡上皮细胞之间以及固有膜内.形态多样,呈圆形、锥体形、梭形等.分析认为蛇岛蝮蛇消化道5-HT细胞具有内、外分泌两种作用途径,并且其密度分布可能与其食性、生存环境有关.     

东方铃蟾消化道5-羟色胺免疫活性细胞的免疫组织化学定位

应用5-HT抗血清,以ABC(avidin-biotin-peroxidase complex)免疫组织化学方法,对东方铃蟾(Bombinaorientalis)消化道内的5-HT免疫活性细胞(5-Hydroxytryptamine immunoreactive cell,5-HT cell)进行了免疫组织化学的定位研究和形态学观察,并探讨其分布型的成因及细胞形态与功能的关系。结果表明,5-HT细胞在东方铃蟾消化道的各个部位均有分布,其中以胃贲门部分布密度为最高:(55.73±10.67)个/mm2;胃幽门部次之:(42.99±5.25)个/mm2;直肠部最低:(6.37±4.78)个/mm2。5-HT细胞的形态多样:圆形、椭圆形、锥体形、长锥体形等,其中食管和直肠以圆形和椭圆形为主,小肠部则以长锥体形为主,其细长突起指向肠腔或固有膜。细胞分布于上皮基部、上皮细胞之间、腺泡上皮细胞之间或固有膜内;胃贲门部、胃体及胃幽门部5-HT细胞主要分布于腺泡上皮之间,也有的分布于胃上皮之间;肠部5-HT细胞主要分布于肠上皮之间。提示了东方铃蟾5-HT细胞分布型的形成与各部位消化功能及其食性和食物组成有关;5-HT细胞形态与其内、外、旁分泌功能是相适应的。     

虎斑颈槽蛇消化道5-羟色胺免疫活性内分泌细胞的分布与形态学观察

用免疫组织化学ABC(avidin-biotin-peroxidase complex)法,对虎斑颈槽蛇Rhabdophis tigrinus 5-HT免疫反应阳性内分泌细胞的分布及形态学进行了观察.结果 表明,5-HT阳性细胞从食管到直肠的消化道各段均有分布.细胞密度分布呈"N"型,胃体最高,胃幽门部和胃贲门部次之,空肠最少.5-HT阳性细胞的形态多样,其中贲门和胃以圆形或椭圆形为主,肠道(除直肠)则以锥形为主;广泛分布于上皮基部、上皮细胞之间、腺泡上皮及腺泡之间,有时可见于固有膜内.     

变色树蜥消化道5-羟色胺细胞的免疫组织化学定位

用免疫组织化学ABC法,应用5-羟色胺(5-HT)特异性抗血清,对变色树蜥(Calotes versicolor)消化道内含有5-HT的内分泌细胞进行了免疫组织化学的定位研究和形态学观察。结果显示,5-HT细胞在变色树蜥消化道的各个部位均有分布,分布密度近似呈“M”形,其中以空肠分布密度最高,胃体次之,食管最低。5-HT细胞的形态多样,呈圆形、椭圆形、锥体形、长锥体形等,其中胃、幽门和直肠以圆形和椭圆形为主,小肠则以长锥体形为主,其细长突起指向肠腔或固有膜;细胞分布于上皮基部、上皮细胞之间、腺泡上皮细胞之间或固有膜内;多数细胞以内分泌功能为主,少数细胞具有外分泌功能。比较分析表明,5-HT细胞分布型可能与动物的食性有关。     

长鬣蜥胃肠道5-羟色胺细胞的免疫组织化学定位

研究长鬣蜥消化道内含有的5一羟色胺（5-HT）内分泌细胞的位置和形态,采用ABC（avidin—biotin—peroxidase complex）免疫组织化学法,应用5-HT特异性抗血清,对其消化道内的5-HT细胞进行免疫化学定位。结果：5-HT细胞从胃部到直肠的胃肠道各段均有分布,细胞密度分布以胃部最高,十二指肠次之,回肠最低。5-HT细胞的形态呈圆形、椭圆形和锥体形等,其中胃体部和直肠部以圆形和椭圆形为主,小肠部以锥体形为主;5-HT细胞广泛分布于上皮基部、上皮细胞之间、腺泡上皮及腺泡之间,有时可见于固有膜内。结论：5-HT细胞的密度分布与其食性、食物组成和生活环境有关,5-HT细胞的形态与其内、外分泌是相适应的。     

人胃窦部胃泌素和生长抑素及其相关mRNA表达和定位的研究

目的：了解人胃窦粘膜内胃泌素和生长抑素及其mRNA在细胞内的表达和定位。方法：用免疫细胞化学和原位杂交技术。结果：G细胞内的胃泌素主要位于细胞的基部和侧部,而其mRNA则位于核周和核上区;D细胞内的生长抑素不仅位于细胞的基部,也见于细胞突起,其mRNA则位于核周、核上区以及突起。G、D细胞均有开放型和闭合型。结论：G细胞为内分泌方式,而D细胞在人胃窦部可能存在两种细胞亚群,除旁分泌外,也有内分泌方式。     

不同脊椎动物消化道内5-羟色胺免疫染色细胞的分布

用过氧化物酶——抗过氧化物酶（PAP）法,对乌鳢（Ophiccephalus argus）、中华大蟾蜍（Bufo bufo garaaarizans）、黄喉水龟（Clemmys mutica）、虎皮鹦鹉（Melopsittacus undulatus）和小白鼠（Mus musculus albula）五种脊椎动物消化道内的5-羟色胺（5-hydroxytryptamine,简称5-HT）免疫染色细胞的分布进行了研究。发现各种动物胃肠道（虎皮鹦鹉胃、乌鳢肠及胃贲门除外）均含有5-HT免疫染色细胞,并首次发现黄喉水龟和中华大蟾蜍食道内含有5-HT免疫染色细胞。一般地,各种动物胃内5-HT免疫染色细胞密度最高,十二指肠和大肠次之,小肠最低。5-HT免疫染色细胞位于粘膜上皮或腺上皮细胞间,常有一个或一个以上的细胞突起伸入固有层或肠腔面（或腺腔面）,有些细胞的一端突起伸入固有层,另一端突起伸入肠腔面,表明5-HT免疫染色细胞兼具内分泌或分泌功能。     

Regeneration of endocrine cells in the stomach

A mucosal defect was produced by cryosurgery in the antral and the fundic wall of the rat stomach, and regeneration of gastric endocrine cells was studied 50, 100 and 200 days after operation. Fifty days after the operation, the mucosal defect was completely covered with regenerated epithelium. The regenerated mucosa both in the antral and in the fundic region consisted of mucinous glandular structures. The regenerated mucosa in the corpus remained pseudopyloric in type even 200 days after operation. Regardless of the time after operation, regeneration of endocrine cells was always observed. We could identify G cells and EC cells in the regenerated mucosa of the antrum, and EC cells, A cells and AL cells in the regenerated mucosa of the corpus, respectively. By electron microscopy, endocrine-exocrine cells were frequently encountered. These cells had two different types of intra-cytoplasmic granules; one was an endocrine-specific, small electron-dense granule, and the other a large, lucent mucin droplet-like granule. These findings indicate that the endocrine cells of the stomach are formed from endodermal precursor cells.     

Cell-specific processing of chromogranin A in endocrine cells of the rat stomach.

The rat stomach is rich in endocrine cells. The acid-producing (oxyntic) mucosa contains ECL cells, A-like cells, and somatostatin (D) cells, and the antrum harbours gastrin (G) cells, enterochromaffin (EC) cells and D cells. Although chromogranin A (CgA) occurs in all these cells, its processing appears to differ from one cell type to another. Eleven antisera generated to different regions of rat CgA, two antisera generated to a human (h) CgA sequences, and one to a bovine (b) CgA sequence, respectively, were employed together with antisera directed towards cell-specific markers such as gastrin (G cells), serotonin (EC cells), histidine decarboxylase (ECL cells) and somatostatin (D cells) to characterize the expression of CgA and CgA-derived peptides in the various endocrine cell populations of the rat stomach. In the oxyntic mucosa, antisera raised against CgA(291-319) and CGA(316-321) immunostained D cells exclusively, whereas antisera raised against bCgA(82-91) and CgA(121-128) immunostained A-like cells and D cells. Antisera raised against CgA(318-349) and CgA(437-448) immunostained ECL cells and A-like cells, but not D cells. In the antrum, antisera against CgA(291-319) immunostained D cells, and antisera against CgA(351-356) immunostained G cells. Our observations suggest that each individual endocrine cell type in the rat stomach generates a unique mixture of CgA-derived peptides, probably reflecting cell-specific differences in the post-translational processing of CgA and its peptide products. A panel of antisera that recognize specific domains of CgA may help to identify individual endocrine cell populations.     

The reaction of the endocrine cells of the gastrointestinal tract in response to exposure to 3,6-dichloropicolinic acid

Silver-impregnated argentaffin cells both Ec, D1, G, P, S and K enteroendocrine cell types of rat gastrointestinal mucosa were investigated under light and electron microscopy after single oral administration of 3,6-dichloropicolinic acid. As a result, in pyloric-duodenal region Ec cells after a period of 1 hour had intensively secreted hormones. Ultrastructurally their cytoplasm and secretory granules were covered by expressed vacuolization. These data hypothetically elucidate the role of the endocrine regulations in developing barrier function of the gastrointestinal epithelium.     

幽门螺杆菌感染对慢性胃炎胃窦部EC细胞和CgA细胞的影响

目的探讨幽门螺杆菌（Helicobacter pylori Hp）感染与慢性胃炎（CG）患者胃窦粘膜内肠嗜铬细胞（Enterochromaffin,EC细胞）、嗜铬粒素A细胞（CgA细胞）变化的关系。方法采用免疫细胞化学方法,检测Hp相关性慢性胃炎胃窦部粘膜内EC细胞、CgA细胞的分布。结果1．Hp^＋组CgA^＋细胞数低,与Hp^＋组和正常组比较差异显著（P〈0．01）;2.EC细胞数随病理类型加重呈下降趋势,三组间的差异性极显著（P〈0．01）,慢性萎缩性胃炎组（CAG）CgA^＋细胞数与慢性非萎缩性胃炎（CNAG）组和正常组比较,差异极显著（P〈0．01）。结论Hp感染和慢性胃炎胃窦部EC细胞和CgA细胞之间存在密切关系。     

Serotonin-producing enterochromaffin (EC) cells of gastrointestinal mucosa in dexamethasone-treated rats

The aim of our study was to investigate the morphological, immunohistochemical and ultrastructural changes of rat serotonin-producing enterochromaffin (EC) cells of gastrointestinal mucosa in dexamethasone-treated rats (D). After 12-daily intraperitoneal administration of 2 mg/kg dexamethasone, rats developed diabetes similar to human diabetes type 2. Stomach, small and large intestines were examined. Large serotonin positive EC cells appeared in the corpus mucosa epithelium of D group of rats, although these cells were not present in control (C) rats. Both volume fraction and the number of EC cells per mm(2) of mucosa were significantly increased only in the duodenum. However, the number of EC cells per circular sections of both antrum and small intestine was increased, but reduced both in the ascending and descending colon in D group. The dexamethasone treatment caused a strong reduction in number of granules in the antral EC cells, while it was gradually increased beginning from the jejunum to descending colon. The mean granular content was reduced in the antral EC cells but increased in the jejunal EC cells in D group. In conclusion, the present study showed that morphological changes in gut serotonin-producing EC cells occurred in diabetic rats.     

Subcellular localization of serotonin immunoreactivity in rat enterochromaffin cells

Serotonin immunoreactive material was localized to rat enterochromaffin cells (EC cells) at the subcellular level using antibodies to serotonin (5-HT) raised in rabbits. Ultrathin sections from paraformaldehyde fixed plastic embedded tissues were directly labelled with the 5-HT antiserum, using the protein A-gold technique to visualize the immunoreaction. The 5-HT immunoreactivity (5-HT-IR) in the rat gastrointestinal mucosa was exclusively localized to epithelial EC cells with a low background over other epithelial non-enterochromaffin cells. Quantitative evaluation of the immunoreaction revealed that most of the 5-HT-IR in the cytoplasm of EC cells (60%) was located over the dense cores of the secretory granules. However, a significant part of the cytoplasmic 5-HT-IR (40%) was located outside the dense cores of the secretory granules which suggests that different forms of 5-HT storage may exist.     

Serotonin storage and chromogranins: an experimental study in rat gastric endocrine cells.

Chromogranins (Cg) and secretogranins (Sg) are acidic proteins localized in the secretory granules of a large variety of endocrine cells collectively named APUD cells (amine precursor uptake and decarboxylation). To examine the possible function of Cg/Sg as amine storage proteins, enteroendocrine cells of the rat gastric antral mucosa, i.e., serotonin-containing enterochromaffin (EC)-cells, gastrin (G)-, and somatostatin (D)-cells, were investigated immunohistochemically in serial semi-thin sections of controls and after intervention in serotonin synthesis. CgA and CgB immunoreactivity was determined semiquantitatively by optical density measurements. Experiments included inhibition of serotonin synthesis by p-chlorophenylalanine (pCPA), exogenous application of the serotonin precursor 5-hydroxytryptophan (5-HTP), and a combination of both treatments. The cellular distribution of Cg and the density of its immunoreactivity were closely related to the primary content of serotonin and the ability to store serotonin after 5-HTP application. Thus, Cg may act as amine-binding proteins in enteroendocrine cells, binding most probably being due to ionic interactions between Cg and the biogenic amines. EC- and G-cells, however, differed in their amine-handling properties and in the response of their Cg immunoreactivity after intervention in serotonin synthesis. We conclude, therefore, that the physiological function of Cg as amine storage proteins is restricted to endocrine cells with an endogenous content of amines. In other endocrine cells, exhibiting only a potential amine production, APUD may be considered as a kind of supravital staining without physiological significance.     

Subcellular localization of serotonin immunoreactivity in rat enterochromaffin cells

Summary Serotonin immunoreactive material was localized to rat enterochromaffin cells (EC cells) at the subcellular level using antibodies to serotonin (5-HT) raised in rabbits. Ultrathin sections from paraformaldehyde fixed plastic embedded tissues were directly labelled with the 5-HT antiserum, using the protein A-gold technique to visualize the immunoreaction. The 5-HT immunoreactivity (5-HT-IR) in the rat gastrointestinal mucosa was exclusively localized to epithelial EC cells with a low background over other epithelial non-enterochromaffin cells. Quantitative evaluation of the immunoreaction revealed that most of the 5-HT-IR in the cytoplasm of EC cells (60%) was located over the dense cores of the secretory granules. However, a significant part of the cytoplasmic 5-HT-IR (40%) was located outside the dense cores of the secretory granules which suggests that different forms of 5-HT storage may exist.Supported by grants from the Swedish Medical Research Council (537, 2207, 5220). Göteborgs Läkaresällskap, and The Medical Faculty of Göteborg     

Immunocytochemical studies on the distribution pattern of daunomycin in rat gastrointestinal tract

The cancer drug daunomycin is used in treatment of leukemia but possesses severe side effects that involve the gastrointestinal tract. We therefore used a newly developed immunocytochemical procedure to determine the distribution of DM in the gastrointestinal tracts of rats after i.v. injection. Two hours after injection, DM was diffusely distributed in nuclei and most parts of the cytoplasm of intestinal epithelial cells. The cytoplasmic immunoreactivity for DM was most pronounced in small granules of the apical cytoplasm. Sixteen hours after injection, DM immunostaining was by and large absent in the villous epithelium but persisted in the intestinal crypts. In addition, staining was also detected in endothelial cells, scattered cells of the lamina propria and in smooth muscle cells. After 5 days, only little staining for DM remained. Similar findings were made in the colon. In the gastric mucosa, DM accumulation persisted at 16 h in some glandular cells but was lost from the surface epithelium. No staining was detected in saline-injected control rats. The distribution of DM accumulation correlated partially with the distribution of apoptotic cells as detected by the TUNEL procedure. Our results pinpoint that DM may exert prolonged effects on glandular and regenerative cells of the gastrointestinal tract—an observation that may explain the gastrointestinal toxicity of the drug. It seems possible that DM accumulation in surface epithelial cells is rapidly cleared through drug transporters.     

Intracellular localization of serotonin in mast cells of the colon in normal and colitis rats

Intracellular localization of serotonin (5-HT) in the mast cells of two phenotypes in normal rat colon and dextran sodium sulphate-induced colitis was studied by immunoelectron microscopy with a quantitative analysis of the distribution of immunogold labelling. Mucosal mast cells in normal rats contained round shape secretory granules with varying electron density. Immunogold labelling for 5-HT was concentrated over the secretory granules. In mucosal mast cells from colitis rats, vacuolated granules without 5-HT labelling were frequently observed and immunogold labelling over the secretory granules was significantly increased compared to controls. On the other hand, connective tissue mast cells in normal rats contained oval shape secretory granules with homogeneous electron density. Their immunogold labelling was diffusely scattered over the secretory granules as well as over the cytoplasm. In connective tissue mast cells from colitis rats, secretory granules with high electron density were increased and the immunogold labelling over the secretory granules was much higher than that in controls. The present results suggest that intracellular localization of 5-HT is different in two phenotypes of mast cells and they may release 5-HT in a different manner. Mucosal mast cells may release 5-HT by a degranulation or exocytosis, while connective tissue mast cells may release 5-HT by a diacrine manner of secretion.