长爪沙鼠肠道5-羟色胺细胞密度的季节变化

为探讨季节性环境对长爪沙鼠肠道5-羟色胺(5-hydroxytryptamine,5-HT)细胞密度动态的影响,于2003
年11 月(冬季)和2004 年7 月(夏季),采用卵白素-生物素-过氧化物酶复合物(avidin-biotin-peroxidase complex,
ABC)免疫组织化学法,对其肠道5-HT 细胞进行了定位研究。结果显示:5-HT 细胞主要分布于肠上皮基
底部和肠腺上皮中,多呈圆形或椭圆形,少数呈长棒状、锥体形或不规则形,其形态学特征无季节性差异。冬
季在小肠密度最高,十二指肠、盲肠和直肠其次,结肠最低;夏季在小肠和十二指肠密度最高,其它各段密度
相似,这可能与其食物质量的季节性变化有关。除十二指肠和结肠外,冬季肠道各段的密度都高于夏季,这有
利于提高处理和消化食物的能力,是对冬季食物质量和摄食量增加的适应。5-HT 细胞的形态学特征和季节动态
说明,长爪沙鼠肠道在细胞水平上可对环境条件的变化产生反应,具有适应性调节的能力。     

蝘蜓消化管内分泌细胞的免疫组织化学定位

目的阐明爬行动物蝘蜓消化管各段内分泌细胞的类型、局部分布、分布密度和形态学特征。方法应用免疫组织化学技术中链霉卵白素-过氧化物酶(S-P)法。结果在蜓消化管内鉴别出5种内分泌细胞,即:5-羟色胺(5-hydroxytryptamine,5-HT)、生长抑素(somatostatin,SS)、胃泌素(gastrin,GAS)、高血糖素(glucagon,GLU)、P-物质(substance P,SP)免疫活性(i mmnoreactive,IR)细胞。5-羟色胺免疫活性细胞是消化管中最主要的内分泌细胞类型,以不同密度分布于消化管各段,其中胃幽门部位分布密度最高。生长抑素免疫活性细胞在消化管内仅局限分布于胃部。胃泌素免疫活性细胞仅见于幽门和十二指肠部位。高血糖素免疫活性细胞仅分布于回肠和直肠。P-物质免疫活性细胞仅出现在直肠部位。蝘蜓消化管内分泌细胞形态多样:圆形、椭圆形、纺锤形、梭形、楔形、锥形以及不规则形。胃部多数内分泌细胞分布于胃腺中,食管和肠管中多数内分泌细胞则分布于上皮细胞间。结论蜓和其它爬行动物胃肠内分泌细胞的分布存在一定共同特征,然而也存在着一些特有的差异。     

蝘蜒消化管内分泌细胞的免疫组织化学定位

目的阐明爬行动物蝘蜒消化管各段内分泌细胞的类型、局部分布、分布密度和形态学特征。方法应用免疫组织化学技术中链霉卵白素一过氧化物酶（S-P）法。结果在蝘蜒消化管内鉴别出5种内分泌细胞,即：5—羟色胺（5-hydroxytryptamine,5-HT）、生长抑素（somatostatin,SS）、胃泌素（gastrin,GAS）、高血糖素（glucagon,GLU）、P-物质（substance P,SP）免疫活性（immnoreactive,IR）细胞。5-羟色胺免疫活性细胞是消化管中最主要的内分泌细胞类型,以不同密度分布于消化管各段,其中胃幽门部位分布密度最高。生长抑素免疫活性细胞在消化管内仅局限分布于胃部。胃泌素免疫活性细胞仅见于幽门和十二指肠部位。高血糖素免疫活性细胞仅分布于回肠和直肠。P-物质免疫活性细胞仅出现在直肠部位。蝘蜒消化管内分泌细胞形态多样：圆形、椭圆形、纺锤形、梭形、楔形、锥形以及不规则形。胃部多数内分泌细胞分布于胃腺中,食管和肠管中多数内分泌细胞则分布于上皮细胞间。结论蝘蜒和其它爬行动物胃肠内分泌细胞的分布存在一定共同特征,然而也存在着一些特有的差异。     

牛蛙胃肠胰系统内分泌细胞的免疫组织化学鉴定与定位

应用过氧化物酶标记的链霉卵白素(S-P)免疫组织化学方法对牛蛙(Rana catesbeiana)胃肠胰系统5种内分泌细胞进行了鉴定与定位.在消化道中检测到了5-羟色胺(5-HT)、生长抑素(SS)、胃泌素(Gas)和胰高血糖素(Glu)细胞.5-HT细胞主要分布于胃幽门部和空肠,食道中偶见.SS细胞主要分布于胃,幽门部较密集,小肠各段少量,直肠和食道偶见.Gas细胞主要分布于小肠各段,胃和直肠中偶见,食道中未检测到.Glu细胞主要分布于胃和直肠,小肠各段偶见,食道中未检测到.在胰腺中检测出了5-HT、SS、Gas、Glu和胰多肽(PP)细胞.SS、Glu和PP细胞数量较多,成簇分布于胰岛中,5-HT和Gas细胞少量,散在分布于胰腺腺泡之间.胃腺部和胰腺内分泌细胞多呈圆形、椭圆形或形态不规则,有的可见明显胞突伸向邻近细胞,胃肠道上皮中的内分泌细胞多呈梭形、楔形或锥形,有的可见明显胞突伸向消化腔.与其它两栖动物相比,牛蛙胃肠胰系统内分泌细胞的存在与分布有一些共性,也存在着种间差异.     

长爪沙鼠脏器重量和肠道长度的季节性变化

小哺乳动物内脏器官的重量和消化道的长度具有可塑性,与其所处的环境密切相关.为进一步了解长爪沙鼠对季节性环境的适应,比较了活捕于内蒙古太仆寺旗的长爪沙鼠的体重、内脏器官的重量及肠道各段长度的性别和季节变化.结果显示:除体重和体长雄鼠高于雌鼠,肝脏的湿重低于雌鼠外,其他指标均未检测到性别差异.雌雄鼠的体重和心脏的湿重都在冬季最高,夏季最低;雄鼠肝脏的湿重夏季最高,春季和冬季最低,雌鼠无季节性变化.睾丸的湿重在春季最高.盲肠和小肠的湿重秋季高于春季,胃和大肠的湿重无季节性差异.小肠的长度冬季最长,夏季最短;盲肠春季最短,大肠春季最长,夏季最短.体重、心脏、消化器官和其他内脏器官的重量,以及消化器官长度的可塑性变化等对于长爪沙鼠适应环境具有重要的意义.     

无蹼壁虎消化道5-羟色胺细胞的免疫组织化学定位

目的研究无蹼壁虎(Gekkoswinhonis)消化道内5-HT免疫反应阳性内分泌细胞的分布以及形态。方法应用显示5-HT的免疫组织化学方法。结果5-HT阳性细胞在无蹼壁虎消化道各段均有分布,其中以十二指肠部位分布密度最多,食道和直肠其次,回肠部位分布密度最低。消化道各段5-HT细胞形态多样,有圆形、椭圆形、梭形、不规则形,其中梭形细胞多具有胞突。结论无蹼壁虎的消化道5-HT细胞的分布、形态与其功能相适应。     

红腹锦鸡胃肠道内分泌细胞的免疫组织化学定位

应用ABC免疫组织化学方法,对红腹锦鸡(Chrysolophus pictus)胃肠道5-羟色胺(5-hydroxtryptamine,5-HT)、胃泌素(gastfin,GAS)、生长抑素(somatostatin,ss)3种内分泌细胞的分布密度和形态进行了观察.结果显示,5-HT细胞在空肠和直肠分布密度最高,回肠和盲肠次之,十二指肠较少,腺胃和肌胃最少;GAS细胞在十二指肠和直肠分布密度最高,其次是空肠和盲肠,腺胃部最低,肌胃则呈免疫阴性;SS细胞数量较少,在直肠、盲肠处分布密度相对高,其次是十二指肠和空肠,腺胃部最低,肌胃则呈免疫阴性.3种内分泌细胞的形态多样,有圆形、椭圆形、锥体形、杆状和不规则形,其中以圆形、椭圆形为主.细胞分布于固有膜、黏膜上皮细胞基部、黏膜上皮细胞之间、腺泡上皮细胞基部或腺泡上皮细胞之间.红腹锦鸡胃肠道内分泌细胞的形态与其内、外分泌功能是相适应的.     

Ghrelin在成年中国黄羽鹌鹑消化道中的定位

为探讨Ghrelin免疫反应阳性细胞在成年中国黄羽鹌鹑(Coturnix japonica)消化道的分布规律及形态学特点。应用免疫组织化学SABC法对成年中国黄羽鹌鹑消化道各段Ghrelin阳性细胞进行定位和形态学研究;利用SPSS 17.0软件,对所得数据进行单因素Dunnett多重比较分析。结果显示,Ghrelin阳性细胞在成年中国黄羽鹌鹑腺胃、十二指肠、空肠、回肠和盲肠均有分布,其中在腺胃分布密度最高,为30.70±6.50,盲肠最低,为1.70±1.56,分布密度从腺胃至盲肠呈逐渐降低的趋势。Ghrelin阳性细胞主要分布于腺胃腺叶细胞、肠道黏膜上皮细胞、肠腺上皮细胞和肠固有层之间,细胞形态多为球形、长柱状和三角形。上述结果说明,Ghrelin阳性细胞在成年中国黄羽鹌鹑消化道分布广泛,根据其细胞形态推测中国黄羽鹌鹑消化道Ghrelin阳性细胞可能具有内分泌和外分泌功能。     

两种爬行动物胃肠道内分泌细胞的免疫组织化学比较研究

目的研究七种胃肠激素内分泌细胞在多疣壁虎及石龙子胃肠道的定位及分布。应用S-P免疫组织化学方法。方法结果5-羟色胺(5-Hydroxytryptamine,5-HT)细胞在两种爬行动物胃肠道各段均有分布,但分布型各不相同;生长抑素(Somatostatin,SS)细胞仅在多疣壁虎胃贲门至十二指肠段分布,而石龙子胃肠道各段均有分布;胃泌素(Gastrin,Gas)细胞分布于多疣壁虎十二指肠和空肠段,石龙子则仅分布于胃幽门部;胰高血糖素(Glucagon,Glu)细胞和P-物质(Substance P,SP)细胞均分布于多疣壁虎胃中各段,而石龙子胰高血糖素细胞分布于回肠、直肠及胃体处,P-物质细胞则分布于除空肠外的胃肠道各段;胰岛素(Insulin,Ins)细胞和胰多肽(Pancreatic polypeptide,PP)细胞在两种爬行动物胃肠道各段均未检出。结论两种爬行动物胃肠道内分泌细胞的分布既存在着一定共性,体现了两消化生理的共同点;同时也存在着较大的种间差异。     

循环饥饿投喂对大鼠消化道嗜银细胞形态及分布的影响

为了研究循环饥饿投喂对大鼠(Rattus norvegicus)消化道内嗜银细胞的分布密度及形态功能的影响,本实验采用Grimelius银染法观察和测定循环饥饿投喂(饥饿1 d,投喂1 d,周期为14 d)期间大鼠消化道嗜银细胞形态功能及密度分布。结果表明,实验组(即循环饥饿投喂组)和对照组(正常喂食组)大鼠消化道嗜银细胞除食管外均有分布,形态上对照组嗜银细胞以椭圆形和锥体形为主,实验组嗜银细胞则主要以锥体形为主;两组大鼠消化道嗜银细胞的分布密度高峰都位于胃,密度低谷对照组位于空肠、盲肠、回肠和直肠,实验组位于空肠到直肠各段;实验组大鼠消化道嗜银细胞分布密度在贲门和幽门部极显著低于对照组(P <0.01),结肠显著低于对照组(P <0.05),说明循环饥饿投喂会明显改变消化道嗜银细胞的形态并降低细胞数量,这可能与内分泌细胞的功能改变有关。     

白条草蜥消化道内分泌细胞的免疫组织化学

应用6种胃肠激素抗血清和免疫组织化学ABC法(avidin-biotin complex method),对白条草蜥(Takydromus wolteri)消化道内分泌细胞进行了免疫组织化学定位研究和形态学观察。结果表明,5-羟色胺细胞较其他5种内分泌细胞的分布更为广泛,整个消化道中(即从食管到直肠)均有分布,其分布密度高峰位于幽门。食管、回肠和直肠未检测到生长抑素细胞,生长抑素细胞在幽门部分布密度最高,总体来说生长抑素细胞的分布在胃部较高而在小肠部较低。胃泌素细胞和胰多肽细胞分布在小肠,均在十二指肠分布密度最高。胰高血糖素细胞在胃幽门部分布密度最高,十二指肠、空肠次之,回肠分布密度最低。P-物质细胞仅分布于幽门部。6种内分泌细胞以圆形和锥体形为主,它们广泛分布于消化道黏膜之间、腺泡上皮细胞之间及上皮细胞基部。内分泌细胞的密度分布与其食性、食物组成和生活环境有关,它们的形态与其内、外分泌功能是相适应的。     

蓝狐消化道内分泌细胞的免疫组化研究

蓝狐又名北极狐(Alopex lagopus),属于食肉目(Carnivora),犬科(Canidae),北极狐属(Alopex).     

Existence of serotonin and neuropeptides-immunoreactive endocrine cells in the small and large intestines of the mole-rats (Spalax leucodon)

The present study was conducted to clarify the regional distribution and relative frequency of endocrine cells secreting serotonin, substance P (SP), cholecystokinin-8 (CCK-8), vasoactive intestinal polypeptide (VIP) and neurotensin in the small and large intestine of the mole-rats (Spalax leucodon), by specific immunohistochemical methods. In the small and large intestine of mole-rats (Spalax leucodon), serotonin, SP and VIP were identified with various frequencies, but CCK-8 and neurotensin were not observed. Most of the IR cells in the small and large intestine were located in the intestinal crypt and epithelium however, they were more frequency in the intestinal crypt. Serotonin-IR cells were detected throughout the whole intestinal tract, predominantly in the duodenum and colon. SP-IR cells were demonstrated throughout the whole intestinal tract except for the ileum and rectum with highest frequencies in the cecum. VIP-IR cells were found in all parts of the small intestine except for the large intestine.In conclusion, the general distribution patterns and relative frequency of intestinal endocrine cells of the mole-rats (Spalax leucodon) was similar to those of some rodent species. However, some species-dependent unique distributions and frequencies characteristics of endocrine cells were also observed in the present study.     

Distribution of endocrine cells in the digestive tract of Alligator sinensis during the active and hibernating period

The digestive tract is the largest endocrine organ in the body; the distribution pattern of endocrine cells varies with different pathological and physiological states. The aim of the present study was to investigate the distributed density of 5-hydroxytryptamine (5-HT), gastrin (GAS), somatostatin (SS) and vasoactive intestinal peptide (VIP) immunoreactive (IR) cells in the digestive tract of Alligator sinensis during the active and hibernating period by immunohistochemical (IHC) method. The results indicated that 5-HT-IR cells were distributed throughout the entire digestive tract, which were most predominant in duodenum and jejunum. The density increased significantly in stomach and duodenum during hibernation. GAS-IR cells were limited in small stomach and small intestine. The density decreased significantly in small stomach during hibernation, while increased in duodenum. What's more, most of the endocrine cells in duodenum were generally spindle shaped with long cytoplasmic processes ending in the lumen during hibernation. SS-IR cells were limited in stomach and small stomach. The density increased in stomach while decreased in small stomach during hibernation, meanwhile, fewer IR cells occurred in small intestine. VIP-IR cells occurred in stomach and small stomach. The density decreased in small stomach, while increased in stomach during hibernation. These results indicated that the endocrine cells in different parts of digestive tract varied differently during hibernation, their changes were adaptive response to the hibernation.     

Expression of intermediate conductance potassium channel immunoreactivity in neurons and epithelial cells of the rat gastrointestinal tract

Recent functional evidence suggests that intermediate conductance calcium-activated potassium channels (IK channels) occur in neurons in the small intestine and in mucosal epithelial cells in the colon. This study was undertaken to investigate whether IK channel immunoreactivity occurs at these and at other sites in the gastrointestinal tract of the rat. IK channel immunoreactivity was found in nerve cell bodies throughout the gastrointestinal tract, from the esophagus to the rectum. It was revealed in the initial segments of the axons, but not in axon terminals. The majority of immunoreactive neurons had Dogiel type II morphology and in the myenteric plexus of the ileum all immunoreactive neurons were of this shape. Intrinsic primary afferent neurons in the rat small intestine are Dogiel type II neurons that are immunoreactive for calretinin, and it was found that almost all the IK channel immunoreactive neurons were also calretinin immunoreactive. IK channel immunoreactivity also occurred in calretinin-immunoreactive, Dogiel type II neurons in the caecum. Epithelial cells of the mucosal lining were immunoreactive in the esophagus, stomach, small and large intestines. In the intestines, the immunoreactivity occurred in transporting enterocytes, but not in mucous cells. Immunoreactivity was at both the apical and basolateral surfaces. A small proportion of mucosal endocrine cells was immunoreactive in the duodenum, ileum and caecum, but not in the stomach, proximal colon, distal colon or rectum. There was immunoreactivity of vascular endothelial cells. It is concluded that IK channels are located on cell bodies and proximal parts of axons of intrinsic primary afferent neurons, where, from functional studies, they would be predicted to lower neuronal excitability when opened in response to calcium entry. In the mucosa of the small and large intestine, IK channels are probably involved in control of potassium exchange, and in the esophageal and gastric mucosa they are possibly involved in control of cell volume in response to osmotic challenge.     

The thickness of the mucus layer in different segments of the rat intestine

Summary The thickness of the pre-epithelial mucus layer has been measured in different gut segments of rats kept under normal (ad libitum) feeding conditions, and after 48 h of fasting, using cryostat sections and celloidin stabilization from samples containing luminal contents. The mucus layer of the stomach, duodenum, jejunum, ileum, caecum, proximal colon, colon transversum, distal colon and rectum was studied in five groups of male rats (10, 40, 70 and 150 days of age, and older). Underad libitum feeding conditions, a distinct and continuous mucus layer, with a thickness of more than 3 μm, was only observed in the colon transversum, in the distal colon, in the rectum and in the stomach. No pre-epithelial mucus layer was observed in the duodenum and jejunum where the glycocalix from the apical membrane of the superficial cells appeared to be in a direct contact with the luminal ingesta. In the ileum, caecum and the proximal colon, the surface epithelium of the mucosa was only partly covered by a mucus layer of highly variable thickness. After 48 h of fasting, a mucus layer of 28.8 ± 25.6 μm and 93.3 ± 59.4 μm thickness, respectively, was found in the duodenum and jejunum of adult rats, but no increase in the thickness of the mucus layer was observed in the rat hind gut.     

Distribution of enteric nerve cells that project to the coeliac ganglion of the guinea-pig

Summary The digestive tract of the guinea-pig, from the esophagus to the rectum, was examined in detail to determine the distribution and relative abundances of neurons in these organs that project to the coeliac ganglion and the routes by which their axons reach the ganglion. A retrogradely transported neuronal marker, Fast Blue, was injected into the coeliac ganglion. The esophagus, stomach, gallbladder, pancreas, duodenum, small intestine, caecum, proximal colon, distal colon and rectum were analysed for labelled neurons. Retrogradely labelled neurons were found only in the myenteric plexus of these organs, and in the pancreas. No labelled neurons were found in the gallbladder or the fundus of the stomach, or in the submucous plexus of any region. A small number of labelled neurons was found in the gastric antrum. An increasing density of labelled neurons was found along the duodenum. Similarly, an increasing density of labelled neurons was found from proximal to distal along the jejuno-ileum. However, the greates densities of labelled neurons were in the large intestine. many labelled neurons were found in the caecum, including a high density underneath its taeniae. An increasing density of labelled neurons was found along the length of the proximal colon, and labelled neurons were found in the distal colon and rectum. In total, more labelled cell bodies occurred in the large intestine than in the small intestine. The routes taken by the axons of viscerofugal neurons were ascertained by lesioning the nerve bundles which accompany vessels supplying regions of the digestive tract. Viscerofugal neurons of the caecum project to the coeliac ganglion via the ileocaeco-colic nerves; neurons in the proximal colon project to the ganglion via the right colic nerves, and neurons in the distal colon project to the ganglion via the mid colic and intermesenteric nerves. Neurons in the rectum project to the coeliac ganglion via the intermesenteric nerves. These nerves (except for the intermesenterics) all join nerve bundles from the small intestine that follow the superior mesenteric artery. All viscerofugal neurons of the caecum were calbindin-immunoreactive (calb-IR) and 94% were immunoreactive for vasoactive intestinal peptide (VIP-IR). In the proximal colon, 49% of labelled neurons were calb-IR and 85% were VIP-IR. In the distal colon, 80% of labelled neurons were calb-IR and 71% were VIP-IR.