α1-肾上腺素受体在颌下腺的表达及苯肾上腺素对唾液分泌调节的动物实验

目的研究α-肾上腺素受体亚型在家兔颌下腺的表达和分布，及其激动剂——苯肾上腺素促家兔颌下腺唾液分泌的相关机制。方法应用RT—PCR和Western blot检测家兔正常颌下腺α1-肾上腺素受体亚型mRNA及蛋白质的表达；免疫组化法检测颌下腺α1-肾上腺素受体亚型的分布及水通道蛋白5的表达；经颌下腺导管插管给予（1×10^-8）-（1×10^-6）moL／L的苯肾上腺素，观察家兔心率和血压的变化及促颌下腺唾液分泌的量效关系。结果家兔颌下腺有α1A-α1B和α1D-肾上腺素受体3种亚型的mRNA及蛋白质的表达，并广泛分布于导管和腺泡细胞的胞膜及胞质中。给予1×10^-7moL／L苯肾上腺素7d，促进颌下腺唾液分泌增加，而对心率、血压无明显影响；水通道蛋白5在腺泡及导管细胞的顶膜和侧膜的表达增加。结论家兔颌下腺存在α1A-、α1B-和α1D-肾上腺素受体3种亚型的mRNA和蛋白质的表达。经颌下腺导管给予低剂量苯肾上腺素促进唾液分泌是安全有效的；水通道蛋白5的表达增加可能与苯肾上腺素促唾液分泌的机制有关，该研究为临床治疗领下腺功能低下提供了初步依据。     

黄芪丹参对干燥综合征模型大鼠颌下腺组织的水通道蛋白-5表达的影响

目的 探讨黄芪合并丹参对干燥综合征模型大鼠颌下腺组织水通道蛋白-5(AQP5)的影响。方法 自身同种鼠抗原合并百白破疫苗加强免疫法免疫模型动物;用Western blot分析SS大鼠颌下腺AQP5表达的影响。结果 免疫动物出现类似SS的病理改变,存在大量淋巴细胞浸润,提示免疫造模成功。Western blot检测显示各组均出现分子量为42 KD的条带。空白对照组AQP5表达值正常(1.35±0.13),造模生理盐水组AQP5表达值(1.03±0.08)明显减少,造模中药高剂量组AQP5表达值较造模生理盐水组明显增强(1.31±0.15)。与空白对照组比较,造模生理盐水组AQP5表达显著减少(P<0.05);与造模生理盐水组比较造模中药高剂量组AQP5有表达显著增加(P<0.01)。结论 唾液流量的增加、颌下腺指数降低提示中药黄芪、丹参有改善唾液腺分泌唾液的功能;Western blot检测显示黄芪、丹参通过增强颌下腺水分子通道的释放,上调AQP5的表达,扩大颌下腺水分子的滤过,缓解口腔干燥的症状。?     

一次性18Gy放射对大鼠颌下腺损伤的实验研究

目的:观察一次性18 Gy放射对大鼠颌下腺组织学形态和唾液流率的改变。方法:40只大鼠随机分为实验组和对照组,每组20只。实验组一次性18 Gy局部照射大鼠颌下腺区域,对照组只麻醉不放射。8周后处死所有大鼠,处死前插管法提取大鼠颌下腺唾液,称取其质量,计算唾液流率,比较两组唾液流率的改变。处死后取颌下腺组织,经4%多聚甲醛固定,切片,HE染色,镜下观察颌下腺的组织学形态。结果:放射后实验组进食进水量下降、活动减少。实验组饮水频率高于对照组。对照组的唾液流率为(18.64±8.23)μL/min,实验组的唾液流率是对照组的57.42%,为(10.70±2.22)μL/min。HE染色显示,放射后实验组颌下腺细胞变性,间质血管充血,腺泡细胞内的空泡数量明显增多。结论:放射后大鼠颌下腺唾液流率明显降低,放射后8周,组织学形态出现显著变化。放疗对大鼠颌下腺组织学形态和唾液分泌功能的远期影响,尚需进一步观察和研究。     

大鼠腮腺及颌下腺唾液的收集

目的:探讨大鼠腮腺及颌下腺唾液的收集方法。方法:采用微型Lashley吸盘法收集大鼠腮腺唾液,经口内颌下腺导管口直接插管法收集颌下腺唾液。毛果芸香碱刺激唾液分泌,假设唾液的比重为1.0 g/cm3,以唾液重量代表其体积,记录唾液流率。结果:大鼠腮腺唾液流率(9.9±1.4)μL/m in,颌下腺导管插管唾液流率(19.9±10.8)μL/m in。结论:可以采用微型吸盘法收集大鼠腮腺唾液,经口内颌下腺导管口直接插管法收集大鼠颌下腺唾液。     

自体颌下腺移植治疗角结膜干燥症术后泪液成份分析

目的 了解自体颌下腺移植术后泪液成份的变化。方法 采用实验室常规方法检测移植术后8例患者泪液及30例正常人泪液,颌下腺液的化学成份并进行比较。测定项目包括;淀粉酶,溶菌酶,钠、钾、钙、磷,渗透压,尿素、肌酐,尿酸,总蛋白、免疫球蛋白,甘油三脂,葡萄糖,酸碱度等。结果 正常人泪液中各种成分在唾液中均可检出;移植术后的“唾液泪液”（S-T）中淀粉酶（AMY）呈高分泌状态;钠（Na)含量低于正常泪液;渗透压介于唾液与泪液之间,呈低渗,尿酸（Ua)含量高于正常泪液;溶菌酶（LZ）含量明显低于正常泪液。结论 颌下腺移植术后S-T液的性质介于正常泪液与颌下腺液之间;高分泌水平的AMY表明移植腺体保持良好的分泌功能。AMY可作为腺体移植成活的生化标准;某些成分的明显差异能否对移植效果造成影响,有待进一步观察。     

失副交感神经支配对大鼠颌下腺分泌功能的影响

目的观察大鼠颌下腺失副交感神经支配后近远期分泌功能的变化,探讨失副交感神经支配调控颌下腺分泌、治疗口干的可能性。方法将20只雄性成年SD大鼠分为实验组（12只）和正常对照组（8只）。实验组行右侧鼓舌神经切除术,实验组左侧及正常对照组颌下腺均未处理。术后1、12和24周采用希尔默试验（Schirmer test）检测颌下腺的分泌功能。结果 进食刺激状态下实验组手术侧腺体的唾液流率明显低于非手术侧[(27.13±3.28)、(33.00±12.98)和(27.50±5.20) mm]和正常对照组[(30.25±3.86)、(28.00±3.46)和(27.00±4.32) mm](P＜0.05),证实术后颌下腺失去副交感神经支配。但在静息状态下,术后各时间点实验组手术侧腺体的唾液流率显著高于非手术侧[(1.91±0.62)、( 1.33±0.29)和(2.38±1.79) mm]和正常对照组[(1.90±0.34)、(1.53±0.46)和(1.48±0.39) mm](P＜0.05);非手术侧与正常对照组腺体唾液流率的差异无统计学意义。结论采用颌下腺失副交感神经支配治疗口干有一定的可能性。     

AQP6和AQP5在人下颌下腺上的免疫组化定位

目的检测水通道蛋白亚型AQP6和AQP5在人下颌下腺的分布情况。方法对源自10例行颈淋巴清扫术患者的正常颌下腺组织,通过免疫组织化学染色方法,标记确定人下颌下腺组织中AQP6和AQP5的分布情况。结果 AQP6在部分颌下腺腺泡细胞质中表达。AQP5在浆液性腺泡和粘液性腺泡顶膜以及分泌小管均有表达,而闰管和纹状管未见表达。结论 AQP6在部分颌下腺腺泡细胞中表达,与AQP5相协调,参与唾液中水和阴离子的分泌调节。     

颌下腺部分切除术后腺体外分泌功能的临床研究

目的研究颌下腺部分切除术后颌下腺外分泌功能的改变。方法 52例颌下腺良性肿瘤患者,随机分为A、B两组,A组患者行颌下腺肿瘤和瘤周腺体区域性切除术,即颌下腺部分切除术;B组患者行肿瘤和颌下腺腺体全切除术,即常规颌下腺良性肿瘤手术。术前及术后1周、2周、1个月及半年,分别检测2组患者5 min内舌下区平均静息唾液分泌量,并进行对照分析。结果术前2组患者5 min内舌下区平均静息唾液分泌量基本相等;术后1周、2周、1个月及半年,5 min内舌下区平均静息唾液分泌量A组明显高于B组,A组患者5 min内舌下区平均静息唾液分泌量于术后1周、2周、1个月及半年的顺序递增,术后半年唾液分泌量比术前稍有减少,而B组患者术后唾液分泌量约为术前一半。结论颌下腺部分切除术充分保留了颌下腺的外分泌功能,保留的颌下腺组织外分泌功能随时间的推移逐步恢复。     

唾液变化与胃食管反流病

两千多年前,古希腊人就发现了唾液的医疗价值,他们使用无毒蛇的唾液涂抹伤口,促进伤口愈合[1]。自然界的许多动物也有用舌头舔伤口的习惯,这是一种条件反射,还是因为唾液除了润滑、助消化的功能外,还能促进伤口愈合？Cohen[2]于1962年从大鼠颌下腺中发现表皮生长因子（EGF）,由此引起了人们对唾液成分与上消化道疾病关系进行研究的浓厚兴趣。     

唾液蛋白质组学的研究进展与应用

唾液是人体及其他哺乳动物一种重要且必需的体液,近年,成为除血浆、血清、尿液以外另一种检测人体生理、病理状态的有效工具[1-2].唾液主要由腮腺、舌下腺、下颌下腺三对大唾液腺和大量口腔黏膜下的小唾液腺分泌,并含有部分非唾液腺来源成分,主要包括龈沟液、口腔固有菌群及其产物、上呼吸道分泌物、口腔屏障渗透而来的血浆及血细胞、脱落的口腔上皮细胞以及食物残渣等[3].安静状态下唾液成分主要来源于舌下腺和颌下腺,而刺激状态下则主要由腮腺分泌的唾液组成[4-5],这种差异在实验设计时可作为唾液收集形式的依据.     

Salivary glands: applied anatomy and clinical correlates.

The major salivary glands include the paired parotid, submandibular and sublingual glands. Salivary glands act as accessory digestive glands and produce a secretion referred to as saliva. Saliva has lubricating, cleansing, digestive and antimicrobial properties. The parotid is the largest salivary gland and saliva is secreted into the mouth via the parotid duct (Stensen's duct). The submandibular gland lies inferior to the body of the mandible and is susceptible to sialolithiases. Drainage is via the duct of the submandibular gland (Wharton's duct) into the floor of the mouth on either side of the lingual frenulum. The sublingual glands are situated under the mucosa in the floor of the mouth, on the sides of the tongue. These glands are in relationship to important nerves in the surrounding tissue. Disease processes such as chronic intraparenchymal sialolithiasis and neoplastic changes frequently mandate surgical removal of the underlying salivary gland. Detailed, applied knowledge of anatomy on a regional basis is required to avoid inadvertent nerve damage during surgery and resulting litigation.     

The contribution of oral minor mucous gland secretions to the volume of whole saliva in man

To determine the contribution of minor mucous gland secretions to total saliva by a direct method, flow rates of both unstimulated and sour lemon drop (SLD)-stimulated saliva were initially determined in 15 subjects. The right and left lingual nerves were then anaesthetized to halt submandibular and sublingual secretion, and both parotid ducts were cannulated. The only remaining saliva in the mouth was that secreted by minor salivary glands. Unstimulated and SLD-stimulated minor mucous gland secretions were then collected and the median percentage contributions to whole saliva were calculated to be 8 and 7 per cent, respectively. Comparable results were obtained on 3 subjects using an indirect method similar to that of Schneyer (1956). With the left parotid duct cannulated, subjects maintained a constant, SLD-stimulated, left parotid flow rate of 1 ml/min and the remaining mixed saliva was collected to determine its flow rate. The right parotid and the submandibular and sublingual glands were then also cannulated and the flow rate from these glands determined whilst that from the left parotid was maintained at 1 ml/min. The contribution from minor mucous glands was the difference between the flow rate of mixed saliva and the combined flow rate from the right parotid, submandibular and sublingual glands.     

The effect of food consistency and dehydration on reflex parotid and submandibular salivary secretion in conscious rats

Changes in salivary secretion with different consistency of diet and dehydration were studied in male Wistar rats under unrestricted conditions. To measure the salivary secretion, a stop-flow method was used. There was little unstimulated salivary secretion from the parotid and submandibular glands, but eating solid, powdered, and liquid diets induced parotid and submandibular saliva. There was no significant change in the volume and flow rate of saliva in bilateral parotid glands during the eating of solid diets. The solid and powdered diets induced significantly more salivary secretion from the parotid gland than did the liquid. The salivary flow rate with solid diets was significantly greater from the parotid gland than from the submandibular. On the other hand, the salivary flow rate with the liquid diet was significantly smaller from the parotid gland than from the submandibular. Appreciable amounts of submandibular saliva, but little parotid saliva were secreted during grooming. Clearly, parotid and submandibular saliva have different roles in the rat. When injected intraperitoneally with 1.5 M NaCl solution or water-deprived for 24 h, rats took longer to eat the solid diets, and had increased salivary volume and decreased flow rate from the parotid gland. These results indicate that the moisture content of the diet and the dryness of the mouth alters the volume of parotid saliva secreted in rats and show that parotid saliva plays an important part in mastication and swallowing.     

The biphasic effect of extracellular glucose concentration on carbachol‐induced fluid secretion from mouse submandibular glands

Cholinergic agonists evoke elevations of the cytoplasmic free‐calcium concentration ([Ca²⁺]_i) to stimulate fluid secretion in salivary glands. Salivary flow rates are significantly reduced in diabetic patients. However, it remains elusive how salivary secretion is impaired in diabetes. Here, we used an ex vivo submandibular gland perfusion technique to characterize the dependency of salivary flow rates on extracellular glucose concentration and activities of glucose transporters expressed in the glands. The cholinergic agonist carbachol (CCh) induced sustained fluid secretion, the rates of which were modulated by the extracellular glucose concentration in a biphasic manner. Both lowering the extracellular glucose concentration to less than 2.5 mM and elevating it to higher than 5 mM resulted in decreased CCh‐induced fluid secretion. The CCh‐induced salivary flow was suppressed by phlorizin, an inhibitor of the sodium–glucose cotransporter 1 (SGLT1) located basolaterally in submandibular acinar cells, which is altered at the protein expression level in diabetic animal models. Our data suggest that SGLT1‐mediated glucose uptake in acinar cells is required to maintain the fluid secretion by sustaining Cl^? secretion in real‐time. High extracellular glucose levels may suppress the CCh‐induced secretion of salivary fluid by altering the activities of ion channels and transporters downstream of [Ca²⁺]_i signals.     

Minor gland and whole saliva in postmenopausal women using a low potency oestrogen (oestriol)

Many women undergo hormone replacement therapy in order to relieve menopausal and postmenopausal symptoms. Oral discomfort is common among these symptoms and studies have shown that the stimulated whole saliva flow rate is increased after combined oestradiol and progesterone replacement therapy. There is, however, no data regarding the effect of other oestrogens or of oestrogen alone on whole and minor gland saliva. In the present study, the flow rate from minor salivary glands (buccal, labial and palatal) and the secretion rate and buffer capacity of whole saliva was examined in 18 postmenopausal women (61-76 years) prior to, and during 1 year of a low potency oestrogen (oestriol) use. The ability of whole saliva to aggregate and mediate bacterial adherence as well as subjective feelings of dry mouth was also examined. For comparison, the same variables were examined in nine peri- and postmenopausal, non-medicated women (reference group, 53-61 years). During hormone treatment, the labial saliva flow was significantly increased and the complaints of dry mouth reduced. Increased stimulated whole saliva flow was seen in both the hormone and reference groups. This was also true for the stimulated whole saliva buffer capacity, which was increased parallel to the flow rate. The secretion rates were generally lower in the hormone group compared to the reference group throughout the study period. Except for stimulated whole saliva, statistical analysis at baseline revealed no age-related reduction of the saliva flow rates. The ability of whole saliva to mediate aggregation of Actinomyces naeslundii was significantly decreased after hormone treatment. Thus, the present findings indicate that a low dose oestrogen (oestriol) may affect the flow rate of labial salivary glands and the bacterial aggregation activity of whole saliva.     

调控涎腺细胞分泌的受体及其信号转导的研究进展

涎腺细胞膜表面的受体及其所介导的信号转导通路是调控涎腺分泌的重要途径。本文概要介绍了毒蕈碱型胆碱受体、α1-肾上腺素受体、β-肾上腺素受体及辣椒素受体在正常颌下腺的表达及其对唾液分泌的调控作用,重点介绍了作者所进行的涎腺细胞受体对失神经支配的移植颌下腺分泌调控作用的研究结果。     

Levels of pre-kallikrein in resting and stimulated human parotid and submandibular saliva

Salivary tissue kallikrein is stored in an active form in human salivary glands. Pre-kallikrein has been demonstrated in mixed saliva, but it is not clear if the various salivary glands contribute equally. This study set out to determine if pre-kallikrein is present in human parotid and submandibular salivas at rest, whether levels change during stimulation, and to compare the pattern of pre-kallikrein and kallikrein secretion with that of total protein. Resting and citric acid-stimulated parotid and submandibular, and gum-stimulated parotid saliva samples were collected from 6 healthy subjects. Salivary flows were determined gravimetrically. Total protein concentration and kallikrein enzymic activity were assayed using standard techniques. Pre-kallikrein was assayed following trypsinisation of duplicate samples. Pre-kallikrein was present in parotid and submandibular ductal saliva. Proportions of pre-kallikrein and active kallikrein were similar in salivas secreted at rest and during stimulation, and both outputs mirrored protein output in both major glands. Gum-stimulated parotid saliva showed lower activity than resting, and no differences were seen between resting and stimulated submandibular samples.     

The physiology of salivary secretion

Saliva in the mouth is a biofluid produced mainly by three pairs of major salivary glands – the submandibular, parotid and sublingual glands – along with secretions from many minor submucosal salivary glands. Salivary gland secretion is a nerve‐mediated reflex and the volume of saliva secreted is dependent on the intensity and type of taste and on chemosensory, masticatory or tactile stimulation. Long periods of low (resting or unstimulated) flow are broken by short periods of high flow, which is stimulated by taste and mastication. The nerve‐mediated salivary reflex is modulated by nerve signals from other centers in the central nervous system, which is most obvious as hyposalivation at times of anxiety. An example of other neurohormonal influences on the salivary reflex is the circadian rhythm, which affects salivary flow and ionic composition. Cholinergic parasympathetic and adrenergic sympathetic autonomic nerves evoke salivary secretion, signaling through muscarinic M3 and adrenoceptors on salivary acinar cells and leading to secretion of fluid and salivary proteins. Saliva gland acinar cells are chloride and sodium secreting, and the isotonic fluid produced is rendered hypotonic by salivary gland duct cells as it flows to the mouth. The major proteins present in saliva are secreted by salivary glands, creating viscoelasticity and enabling the coating of oral surfaces with saliva. Salivary films are essential for maintaining oral health and regulating the oral microbiome. Saliva in the mouth contains a range of validated and potential disease biomarkers derived from epithelial cells, neutrophils, the microbiome, gingival crevicular fluid and serum. For example, cortisol levels are used in the assessment of stress, matrix metalloproteinases‐8 and ‐9 appear to be promising markers of caries and periodontal disease, and a panel of mRNA and proteins has been proposed as a marker of oral squamous cell carcinoma. Understanding the mechanisms by which components enter saliva is an important aspect of validating their use as biomarkers of health and disease.     

生津活血中药在头颈部放疗中对涎腺功能影响的研究

目的探讨生津活血中药在头颈部肿瘤患者放疗过程中对涎腺功能的影响。方法将38例首程放疗的患者随机分为实验组(中药加放疗)18例和对照组(单纯放疗)20例。对放疗前及放疗不同剂量时的口干程度、pH值、唾液流率及淀粉酶浓度进行比较。结果随放疗剂量的增加,2组患者口干程度增加,唾液流率与淀粉酶浓度均降低。在放疗至20、40 Gy时实验组的唾液流率和淀粉酶浓度均较对照组高。但在达到60 Gy时,2组数据则趋于接近。另外,患者的主观口干程度与客观的唾液流率下降程度之间并不直接对应。结论①头颈部肿瘤患者在放疗过程中辅以生津活血中药,可在一定程度上改善口干症状,但并不足以预防放射性口干症的发生。②患者的口干严重程度和唾液流率下降程度之间并不严格对应,患者主观的口干程度并不能作为反映唾液腺功能受损程度的可靠指标。