5种哺乳动物涎腺造影及解剖比较研究

目的：研究5种动物涎腺造影及解剖形态学特点。方法：选用成年小型猪5只，猕猴2只，新西兰白兔、Wistar大鼠和昆明小鼠各7只，行腮腺和颌下腺造影、解剖学观察，并进行比较分析。结果：5种动物腮腺腺体在大小、重量上有较大差异，腮腺的重量依次为小型猪、人、猕猴、兔、大鼠和小鼠。5种动物的颌下腺差异较大，其中小型猪颌下腺在大小、重量、导管直径及造影表现上较其它动物更接近于人类。结论：在小型猪、猕猴、兔、大鼠和小鼠5种动物中，小型猪的腮腺、颌下腺在重量、大小、导管直径及造影表现上较其它4种动物更接近于人类。     

小型猪与小鼠腮腺、泪腺、垂体超微结构的观察与比较

目的 研究小型猪及小鼠腮腺的超微结构特点,并将腮腺与泪腺、垂体的超微结构对比观察,旨为涎腺基因治疗转基因表达的生物学特性提供腺体形态学的依据.方法选用成年小型猪、昆明种小鼠各5只,分别取腮腺、泪腺、垂体进行超微结构观察.结果小型猪较小鼠的腮腺腺泡细胞内分泌颗粒密度大,质地均匀,细胞器少见,血管内皮细胞内有较多分泌颗粒存在.小型猪与小鼠泪腺超微结构均与各自腮腺相似,小型猪与小鼠垂体结构特点为细胞排列散在,细胞间充满血窦及毛细血管.结论小型猪腮腺腺泡细胞分泌颗粒多,其毛细血管内皮细胞中也可见较多分泌颗粒,提示这些分泌颗粒可能进入血液发挥内分泌功能.     

放疗对小型猪腮腺颌下腺舌下腺微血管损伤影响的实验研究

目的:观察放疗对小型猪腮腺、颌下腺、舌下腺的微血管损伤状况。方法:将6只实验用小型猪分为2组。2组动物进行放疗,将双侧腮腺、颌下腺、舌下腺加入放射野中,放疗组20Gy/每侧,对照组0Gy/每侧。放疗结束后4 h处死两组动物,取两组动物腮腺、颌下腺、舌下腺标本行HE染色与CD31免疫组化染色,观察放疗早期3种腺体微血管密度变化。结果:两组小型猪腮腺、颌下腺、舌下腺CD31阳性染色颗粒数有显著差异(P＜0.05);3个腺体间统计结果有显著性差异(P＜0.05);腮腺与颌下腺及舌下腺有显著性差异(P＜0.05),颌下腺与舌下腺无显著性差异。结论:放疗可导致小型猪腮腺、颌下腺、舌下腺微血管密度明显减低,且各腺体间微血管密度减低有差异,腮腺的损伤程度大于颌下腺和舌下腺。     

二甲基苯丙蒽诱发大鼠颌下腺腺癌的实验研究

目的:建立大鼠颌下腺腺癌动物模型,研究涎腺腺癌组织发生及发病机制.方法:40只SD成年鼠(雌雄各20只),颌下腺导管结扎后,1%二甲基苯丙蒽丙酮液腺体内二次直接注射腺体内诱发大鼠颌下腺腺癌.通过HE染色和免疫组化染色确立大鼠颌下腺腺癌动物模型.结果:结扎后颌下腺细胞增殖活跃,正常腺体与导管结扎后颌下腺PCNA表达存在显著差异(P<0.05).二次追加注射后,仅雌成年鼠形成颌下腺腺癌,生成率为60%.腺癌组织结构为腺管状、乳头状、筛状以及实性状,并有腺癌转移.导管上皮细胞CK19阳性,肌上皮细胞calpolin、CK14阳性.结论:颌下腺恶性肿瘤发生只少需要细胞二次以上基因突变,而且DMBA诱发颌下腺腺癌只发生雌SD成年鼠,涎腺腺癌发生可能与雌激素有关.     

单一剂量单侧腮腺放射损伤对双侧腮腺结构和功能的影响

目的 研究单一大剂量射线照射单侧小型猪腮腺对双侧腮腺结构和功能影响。方法 14只小型猪一侧腮腺用直线加速分别给予15 Gy（7只）和20 Gy（7只）离子射线照射,4只做为空白对照。分别在放射前,放射后4周和16周观察腮腺唾液流率、腺体重量、腺泡面积和组织学变化。结果 4周时,15 Gy和20 Gy照射后放射侧腮腺重量下降达50%;15 Gy照射后放射侧腮腺唾液流率无明显下降,20 Gy照射后放射侧腮腺唾液流率减少约50％。16周时,15 Gy和20 Gy照射后放射侧腮腺重量下降达50%,组织学明显改变,照射后放射侧腮腺流率分别下降约60%及80%。非放射侧腮腺重量及形态均无明显变化,但20 Gy照射后16周时非放射侧腮腺唾液流率明显下降。结论 单一剂量照射后腮腺结构的改变相对唾液流率下降发生较早,唾液流率减少与腺泡面积的减少不完全成正相关。非照射侧腮腺形态变化不明显,但唾液流率明显下降。     

大鼠颌下腺腺病毒介导荧光素酶基因转导及组织学变化

目的 观察大白鼠颌下腺腺病毒介导的荧光素酶基因转导及其组织学变化。方法 将40只Wistar大鼠随机分为5组，经颌下腺导管转导腺病毒介导荧光素酶基因重组体即AdCMVLuc,3d及1、2、4、8周后观察其基因表达及病理变化。结果 颌下腺转基因表达3d时最高，以后逐渐下降，至4周、8周时仍可测到表达。组织病理学变化：3d-1周时可见腺泡受挤压、腺导管扩张；2周时部分腺泡轻度萎缩，腺泡间距离加大；小叶内及小叶间导管周围淋巴细胞呈灶状浸润；4周时可见有腺泡及腺泡腔结构变清晰；8周时腺泡、导管基本恢复正常，炎症不明显。超微结构变化；注入基因后3d，腺泡和导管细胞内可见大量粗面内质网，粘液腺泡中粘液滴增多，融合成片；1周后，导管腔的微绒毛突起减少，胞质内可见线粒体显著增多；2周及4周，腺泡腔可见少量的微绒毛突起及细丝网状物，粘液腺泡中可见粘液滴。基底部可见粗面内质网，基底膜增厚。结论 本研究报道了腺病毒介导的大鼠颌下腺基因转导后的超微结构变化，提示腺体蛋白合成体系功能活跃，大鼠涎腺基因转导能产生生物活性蛋白，腺体有明显炎症反应。     

小型猪腮腺解剖、造影和组织结构观察

目的 观察小型猪正常腮腺的解剖、造影及组织结构，为研究人类腮腺疾病打下基础。方法对１１只中国实验用小型猪的腮腺进行造影、解剖，并在光镜及电镜下观察其结构。结果 造影示主导管细长，行至下颌角后下开发发出分支导管，上下走行，未见副腺体。解剖观察示腮腺重１０～２０ｇ，主导管长１１～１５ｃｍ，直径１～３ｍｍ，腺体呈现三角形位于颌后区，未见副腺体。组织学观察示腮腺由典型的浆液性腺泡组成，腺泡细胞呈锥形，胞浆     

大鼠涎腺放射损伤模型的建立及NBS1的表达变化

目的：研究大鼠涎腺放射损伤模型中NBS1基因的表达,初步探讨其在放射性涎腺上皮细胞损伤修复中的调控作用。方法：放射组40只大鼠以^60Coγ射线分次照射,每次3GY,隔天1次,共5次,累积剂量分别为3、6、9、12、15GY,对照组40只大鼠同期进行麻醉。照射后2-4h,收集大鼠腮腺,颌下腺。应用苏木素-伊红染色（HE）和透射电镜观察涎腺组织的显微和超微结构变化;应用逆转录聚合酶链技术（RT—PCR）检测腮腺、颌下腺NBS1mRNA的表达情况。结果：腮腺较颌下腺组织损伤严重;放射组和正常组比较,腮腺放射剂量9GY组起,颌下腺于12GY组起,NBS1mRNA表达水平减少（P〈0．05）。结论：大鼠涎腺放射损伤模型建立成功,NBS1可能参与涎腺放射损伤修复。     

60Coγ射线照射大鼠涎腺组织后Mrell蛋白表达的初步研究

目的:检测Mre11基因及其蛋白在放疗后的大鼠腮腺和颌下腺组织中的表达变化。方法:选取近交系雄性Wistar大鼠60只,按单次照射0 Gy,3 Gy、6 Gy、9 Gy、12 Gy、15 Gy剂量分成6组,用60Coγ射线照射大鼠头颈部,2h后收集大鼠两侧腮腺和颌下腺组织。用透射电镜观察涎腺上皮细胞超微结构变化;用RT-PCR检测Mre11的基因表达情况;用免疫组化检测Mre11蛋白表达情况。结果:透射电镜显示:放射后大鼠腮腺腺泡细胞胞质和胞膜均出现不同程度的损坏,随着剂量的增加,这种损坏逐渐加剧,未见到再生、恢复的变化。颌下腺和导管变化不明显。RT-PCR检测Mre11mRNA表达无统计学差异。免疫组化检测Mre11蛋白表达有统计学差异。结论:治疗剂量的60Coγ照射对正常涎腺组织呈不可逆的损伤,损伤的程度具有剂量依赖性;大鼠涎腺细胞Mre11mRNA的表达无剂量依赖性;大鼠涎腺细胞Mre11蛋白的表达与辐射剂量以及组织类型有关,随剂量的增加先增强后减弱。     

非肥胖型糖尿病小鼠自发性涎腺炎的发生与发展

目的 观察雌性非肥胖型糖尿病（NOD）小鼠自发性涎腺炎的发生发展过程。方法 选择5、10、15、20周龄雌性NOD小鼠各6只。测定刺激全唾液流率（STFR）、施墨试验、唾液总蛋白、常规HE切片及电镜超微结构观察涎腺组织的改变。以BALB／c小鼠作对照。结果 10、15、20周NOD小鼠STFR、唾液总蛋白均明显低于对照组（P〈0．05），相应的下颌下腺分泌颗粒减少。10周雌性NOD小鼠涎腺炎发病率为4／6，15、20周均为6／6。淋巴细胞浸润主要见于下颌下腺，舌下腺极少，腮腺未见。10周时NOD小鼠已有淋巴细胞浸润灶形成。15周显著增多而且面积增加。STFR与淋巴细胞浸润灶数呈负相关。结论 雌性NOD小鼠5～10周淋巴细胞开始浸润下颌下腺，刺激唾液和蛋白分泌降低。不同腺体受累情况不同。     

Structural and functional injury in minipig salivary glands following fractionated exposure to 70 Gy of ionizing radiation: an animal model for human radiation-induced salivary gland injury

This study explored the feasibility of developing an animal model for radiation-induced salivary gland injury with a radiation protocol identical to current clinical practice. Three male Hanford minipigs were subjected to fractionated daily irradiation with a total dose of 70 Gy; structural and functional measures were compared with those of a control group of minipigs. We found that irradiated submandibular and parotid glands were one-third to one-half the gross size of control glands. Whereas no pathologic changes were noted in control glands, irradiated glands consistently demonstrated significant parenchymal loss with extensive acinar atrophy and interstitial fibrosis, enlarged nuclei in remaining acinar cells, and ductal dilatation and proliferation. Stimulated salivary flow was reduced by 81% in irradiated animals compared with preirradiation flow (P <.001); salivary flow in the control group increased by 30% during the same period (P <.001). The observed radiation-induced structural and functional salivary gland changes are comparable in every respect to those observed following irradiation of human salivary glands.     

Effect of moderate protein-deficiency on ultrastructure in parotid and submandibular acinar cells in the adult rat

Abstract— Powdered diets, of three different levels of protein, were given to groups of adult male rats for 21 days. Two diets with reduced protein content, 5% or 10% casein, were given to experimental rats. A diet with an adequate protein content, 20% casein, was given to controls. A reference group of rats was fed a standard pellet diet for the same period. At the end of the experimental period, the parotid and the submandibular glands were removed and subjected to electron microscopy. The zymogen granules of acinar cells in the parotid glands from the rats receiving the 5% protein diet had lost their normal opaqueness and turned electron lucid whereas parotid glands from the rats fed the 20%, the 10%, and the standard pellet diet exhibited normal acinar cells. The ultrastructure of submandibular acinar cells was not affected in any dietary group.     

Ultrastructural localization of microliths in salivary glands of cat

Although microliths occur in normal human salivary glands and may be an aetiological factor of sialadenitis, little is known of their natural history. In an attempt to remedy this, we investigated a large archival collection of normal and experimental feline parotid, submandibular and sublingual salivary glands. In submandibular and sublingual glands, microliths were detected ultrastructurally in: all types of acinar secretory cells; myoepithelial cells; ductal cells; lumina; intercellular spaces; basement membrane; stroma; macrophages; multinuclear giant cells; and neutrophils. Microliths were not detected ultrastructurally in parotid glands. Microliths appear to form in acinar cells during autophagy and in stagnant secretory material in lumina. Microliths appear to be removed by secretion in the saliva, discharge from cells laterally and basally, and engulfment by macrophages. There appears to be a turnover of microliths, which possibly is upset by secretory inactivity with a resulting accumulation that leads to localized obstruction and sialadenitis.     

A study on changes of liver and salivary glands in rats with experimentally induced liver injuries. Pathological and biochemical observations]

Changes in the salivary glands, liver and pancreas in rats with experimentally induced liver injuries were examined. The injuries (experimental group) were induced by subcutaneous injections of carbon tetrachloride (0.01ml/kg body weight) in a 50% olive-oil solution. The injections were administered twice weekly for 10,20 and 40 weeks. Control animals received the same doses of olive oil during the same periods. 1. In the experimental group, serum glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT) increased remarkably, whereas serum albumin decreased. 2. Swelling of the liver and multiple nodular formations occurred in the experimental group. Liver fibrosis with the formation of pseudolobules indicated a form of liver cirrhosis. 3. No significant histological changes were observed in the pancreases of animals in the 10- and 20-week experimental groups. Vacuolation in the acinar cells was observable in 3 of 8 cases in the 40-week experimental group. 4. In connection with histological findings of parotid glands, vacuolation of the acinar cells occurred in 7 of 12 cases in the 10-week experimental group, in 7 of 8 cases in the 20-week experimental group, and in all 8 cases in the 40-week experimental group. Vacuole numbers and sizes increased as the experimental period was prolonged. 5. Immunohistochemical investigation showed strong positive reactions to the anti-amylase antibody around vacuoles in acinar cells of parotid glands. In unvacuolated acinar cells, on the other hand, only slight positive reaction was observed. 6. Electronmicroscopic observation of the acini revealed greatly enlarged lumina and dilated intercellular canaliculi connected to the lumina. Small vacuoles were observed on the basement of the acini. 7. No such significant changes as fibrosis, vacuolation, and atrophy of acinar cells were observed in the submandibular and sublingual glands of the experimental animals. 8. Serum amylase activity increased more in the experimental than in the control rats. Electrophoretic patterns suggested that in the control group 95 percent of serum amylase was parotid type, and also in the experimental group 95 percent of serum amylase was parotid type. 9. Amylase activity in the parotid glands also increased more in the experimental than in the control animals.     

Tissue distribution of RNAs for cystatins, histatins, statherin, and proline-rich salivary proteins in humans and macaques

The tissue distribution of the mRNAs for a number of salivary proteins [proline-rich proteins (PRPs), statherin, cystatins, and the histatins] has been examined in humans and macaques in order to investigate their possible functions and tissue-specific regulation. We have shown that PRP RNAs (0.8-1.5 kb) are expressed in human and rhesus parotid and submandibular glands, and in the human bronchus. The genes for the acidic and basic PRPs are differentially regulated in these tissues. RNAs for acidic PRPs are predominantly expressed in the submandibular gland, for basic PRPs in the respiratory tract, and for both acidic and basic PRPs in the parotid gland. Protein studies of secretions from these tissues confirm the RNA results. Statherin RNA (0.65 kb) was detected in human and rhesus parotid and submandibular glands and the human bronchus, as well as in rhesus lacrimal glands. Statherin was found by tissue immunoperoxidase staining in the serous cells of respiratory tract submucosal glands, which is the same location for the synthesis of PRPs. Several cystatin RNAs (0.8-1.3 kb) were differentially expressed in human parotid glands, submandibular glands, and the bronchus, and in lacrimal glands from both rhesus and cynomolgus macaques. RNAs (0.6 kb) for the histatins were found only in parotid and submandibular glands. Thus, it appears that PRPs, statherin, and cystatins may play a broader role in the physiology of biological fluids and secretions than previously suspected, since they are found in secretions other than saliva. However, the functions of the histatins are restricted to saliva. These studies also pose some interesting questions regarding the differential expression of these genes in a variety of secretory tissues.     

Effects of hyperleptinemia in rat saliva composition,histology and ultrastructure of the major salivary glands

ObjectiveTo study the effect of the satiety hormone, leptin, in saliva proteome and salivary gland histology and ultrastructure.DesignIncreases in blood leptin levels were induced through mini-pump infusion in male Wistar rats, during a period of 7 days. Saliva was collected before and at the end of the experimental period, for proteomic analysis, and major salivary glands were collected, at the end, for biochemical, histological and ultrastructural analysis.ResultsImmunohistochemistry revealed the presence of leptin receptors in major salivary glands. Salivary amylase levels and enzymatic activity were decreased in saliva, whereas the enzymatic activity of this protein was increased in the cytosol of parotid gland cells. Transmission electron microscopy allowed the observation of high number of electron-dense granules in cytosol of parotid acinar cells, from leptin treated animals.ConclusionsIncreased levels of plasmatic leptin result in changes in saliva composition and salivary glands function. To our knowledge, this is the first study providing evidences for a potential role of leptin in salivary gland secretion and saliva composition. An understanding of how appetite/satiety factors influence saliva composition and how this composition influences food processing in mouth may be relevant in understanding ingestivebehaviour.     

Responses of salivary glands to intake of soft diet

BackgroundModernization has made individuals prefer processed and cooked foods (soft food), but this eating habit may have negative effects on the oral cavity. However, laboratory animals fed with soft diet are commonly used in an attempt to clarify this issue, and various oral tissues, including the salivary glands have been examined. In this review, we summarize the findings of previous studies concerning the responses of salivary glands to daily intake of soft diet.HighlightThe weight of the parotid glands decreased in rodents fed with soft diet (liquid or powder). In atrophic parotid glands, acinar cell shrinkage is histologically observed and the DNA content is reduced, showing that the atrophy is caused by a decrease in the size and number of acinar cells. Immunohistochemical examinations showed that the decrease in the acinar cell number was induced by suppression of acinar cell proliferation and acceleration of apoptosis. The atrophic parotid glands recovered following a change from soft to pellet diet. Other salivary glands, such as the submandibular, sublingual, and palatine glands, responded only slightly to the soft diet feeding.ConclusionAccumulated research data showed that a soft diet negatively affects the parotid glands much more than other salivary glands and that atrophic parotid glands are able to recover by switching to a hard diet. Therefore, it should be emphasized that good eating habits are important for not only digestion but also the health of oral tissues, including the salivary glands.     

Effect of moderate protein-deficiency on ultrastructure in parotid and submandibular acinar cells in the adult rat

Powdered diets, of three different levels of protein, were given to groups of adult male rats for 21 days. Two diets with reduced protein content, 5% or 10% casein, were given to experimental rats. A diet with an adequate protein content, 20% casein, was given to controls. A reference group of rats was fed a standard pellet diet for the same period. At the end of the experimental period, the parotid and the submandibular glands were removed and subjected to electron microscopy. The zymogen granules of acinar cells in the parotid glands from the rats receiving the 5% protein diet had lost their normal opaqueness and turned electron lucid whereas parotid glands from the rats fed the 20%, the 10%, and the standard pellet diet exhibited normal acinar cells. The ultrastructure of submandibular acinar cells was not affected in any dietary group.     

Glycogen content and activities of enzymes involved in the carbohydrate metabolism of the salivary glands of rats during postnatal development

Carbohydrate metabolism was examined in the developing rat salivary glands by analysing enzymatic activity and glycogen content in the postnatal parotid and submandibular glands. The following enzymes of the carbohydrate metabolism, hexokinase (HK), phosphofructokinase-1 (PFK-1), pyruvate kinase (PK), glucose-6-phosphate dehydrogenase (G6PD), and lactate dehydrogenase (LDH) as well as the content of glycogen were determined in the salivary glands of rats aged 2, 7, 14, 21, 30 and 60 days. The specific activity of HK increased from days 2 to 21 and then it decreased up to 60 days old. The values found for the submandibular glands were from 2.5 to 4.9 times higher than those found for the parotid gland, except for rats aged 60 days. PFK-1 showed a different pattern of variation between the glands. In the submandibular gland there was a statistically significant increase in PFK-1 specific activity from 2 to 30 days of age and then, in the 60 days old group a return to level of the rats aged 2 days. In parotid gland, the specific activity of PFK-1 decreased between 2 and 7 days of age, from 7 to 14 days the specific activity increased markedly and from 14 to 60 days old it gradually decreased. The specific activity of PK followed the same pattern of variation in the submandibular and parotid glands, showing no great variation. The specific activity of LDH decreased from 2 to 60 days old in the submandibular glands. In the parotid glands the mean values for this enzyme were higher for the 2 days old group, and then decreased to remained more or less constant. The potential capacity of the pentose phosphate pathway was greater than that of glycolysis at early ages. The glycogen content showed similar variation in both glands. It was initially high and then decreased. In conclusion, our results on the activities of enzymes involved in carbohydrate metabolism in submandibular and parotid glands may be relevant to the initiation of saliva secretion in these animals.