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1.
Carbonic anhydrase VI (CA VI) is a secreted enzyme produced predominantly by serous acinar cells of submandibular and parotid glands. We have investigated the developmental pattern of CA VI production by these glands in the sheep, from fetal life to adulthood, using immunohistochemistry. Also, a specific radioimmunoassay for CA VI was used to measure changes in enzyme expression in the parotid gland postnatally. CA VI is detectable by immunohistochemistry in parotid excretory ducts from 106 days gestation (term is 145 days), in striated ducts from 138 days and in acinar cells from 1 day postnatal. The duct cell content of CA VI declined as the acinar cell population increased, a feature also of CA VI immunoreactivity in the submandibular gland. Production of CA VI by submandibular duct cells was detectable initially at 125 days gestation, and acinar production was not seen before 29 days post-natal. Apart from the differing ontogeny of CA VI production in ducts and acini of parotid and submandibular glands, there was a parallel pattern of CA VI expression during the development of these major salivary glands. With the development of the acinar tissues in the postnatal lamb, there was a dramatic increase (about 600-fold) in the level of expression of CA VI in the parotid gland between days 7 and 59 as measured by radioimmunoassay.  相似文献   

2.
BACKGROUND: Basal folds are slender plications at the basal surface of acinar cells in the salivary glands of many mammalian species. These largely organelle-free folds increase the surface area of the basal plasmalemma manyfold and are unquestionably involved in the translocation of organic and inorganic molecules and water into the acinar cells. METHODS: Specimens of salivary glands were obtained from over 230 species of live-trapped bats from major areas of the globe. Tissues for electron microscopy were fixed and processed by conventional means. RESULTS: A number of the bat species examined had dense material in the intercellular spaces between basal and lateral folds of serous cells in the parotid gland. This intercellular material was particularly prominent in three species of New World bats, viz., Pteronotus parnellii, P quadridens, and Phyllostomus latifolius, and in one species of Old World bats, Chalinolobus argentatus. This dense material, which has a farinaceous texture, appears not to pass through tight junctions, so it is excluded from the lumina of intercellular canaliculi and acini. The dense material originates in the acinar cells--it is carried to the membranes of the folds via coated vesicles, which empty their dense content by exocytosis into the intercellular space. Similar dense material is present in the intercellular spaces of the basal labyrinth of striated ducts in the two species of Pteronotus. The manner in which this material accumulates in the striated duct is unclear. CONCLUSIONS: Although the function of the intracellular dense material is undetermined, it appears to be placed strategically to influence molecular traffic into acinar cells or to modulate the paracellular pathway. From a comparative evolutionary perspective, we hypothesize that, in bats, the combination of basal folds and extracellular densities is associated with insectivory. Similar morphologies appear to be lacking in frugivorous or nectarivorous species.  相似文献   

3.
The rat parotid gland produces a number of well-characterized secretory proteins. Relatively little is known, however, about the onset of their synthesis and cellular localization during gland development. Secretory protein expression was studied in parotid glands of fetal and postnatal rats using light and electron microscopic immunocytochemistry and Northern blotting. Amylase, parotid secretory protein (PSP), common salivary protein-1 (CSP-1), and SMGB were first detected by immunofluorescence in parotid glands of 18 day fetuses. By 5 days after birth, light and electron microscopic immunolabeling localized all of these proteins to the secretory granules of developing acinar cells. Labeling of acinar cells for DNAse I, however, was not observed until 18 days after birth. Between 9 and 25 days, CSP-1 and SMGB reactivity of acinar cells declined, but increased in intercalated duct cells. After 25 days, CSP-1 and SMGB were found only in intercalated ducts, and amylase, PSP, and DNAse I were restricted to acinar cells. Levels of CSP-1 and SMGB mRNA were relatively constant through 21 postnatal days, but declined significantly after that. Amylase and PSP mRNA increased rapidly and continuously from five days after birth to the adult stage. In contrast, DNAse I mRNA was not detectable until 18 days after birth. The immunocytochemical and molecular analyses define three basic patterns of protein expression in the rat parotid gland: proteins whose synthesis is initiated early in development and is maintained in the acinar cells, such as amylase and PSP; proteins that are initially synthesized by immature acinar cells but are restricted to intercalated ducts in the adult gland, such as CSP-1 and SMGB; and proteins that are synthesized only by mature acinar cells and first appear during the third postnatal week, such as DNAse I. The parotid gland exhibits four distinct developmental stages: prenatal, from initiation of the gland rudiment until birth; neonatal, from 1 day up to about 9 days postnatal; transitional, from 9 days to 25 days of age; and adult, from 25 days on. Although differences exist in timing and in the specific proteins expressed, these developmental stages are similar to those seen in the rat submandibular gland. Additionally, the results support the suggestion that intercalated ducts may differentiate from the neonatal acini.  相似文献   

4.
The mechanism of irradiation-induced hypofunction of the salivary glands is a process that is not fully understood. Here we examine the hypothesis that intracellular and redox-active ions of iron and copper, which are associated with the secretion granules, play a catalytic role in the irradiation-induced damage. Rats were subjected to head and neck irradiation (15 Gy X rays) and allowed to recover for 2 months. The function of the parotid and submandibular glands was then determined by pilocarpine-stimulated salivary secretion. A 45% decrease in the function of both glands was obtained when compared to nonirradiated controls. Treatment prior to irradiation (90 min) with cyclocytidine (200 mg/kg) led to a massive degranulation of the parotid gland and yielded nearly complete protection from radiation-induced damage. In contrast, pilocarpine stimulation prior to irradiation led to a marginal degranulation of the parotid gland and yielded only 13% protection. Neither agent caused degranulation of the submandibular gland mucous cells or yielded functional protection of this gland. Treatment with both agents yielded a marked increase in iron, copper and manganese levels in the parotid gland saliva. An analogous marked increase in the redox activity of iron and copper ions was recorded for the parotid saliva stimulated by pilocarpine and cyclocytidine. Pilocarpine-stimulated submandibular gland saliva contained metal levels similar to those of the parotid gland saliva. However, no redox activity and no increase in metal mobilization could be demonstrated in the submandibular gland saliva stimulated by both agents. The correlation between the patterns of gland degranulation, mobilization of redoxactive metals and the protection of gland function, for both parotid and submandibular glands, focuses attention on the catalytic roles played by transition metal ions in promoting free radical reactions, which likely participate in the process of injury to the tissue.  相似文献   

5.
The excurrent duct system of the rat submandibular gland consists of a number of distinct segments. Using the direction of salivary flow as a reference point, these segments are, in order, intercalated duct, granular convoluted tubule, striated duct, excretory duct, main excretory duct (MED), and salivary bladder (which is an expanded portion of the MED). Because these ducts (with the exception of the MED and the salivary bladder) are encased in secretory endpieces, they are difficult to locate and to observe by scanning electron microscopy. A simple method has been devised to rid the gland of these obscuring endpieces so that the detailed architecture of the duct system can be examined. Rat submandibular glands were fixed initially by vascular perfusion with half-strength Karnovsky's fixative. The connective tissue capsule was removed from extirpated glands and the glands remained in fixative for varying lengths of time. For our purposes, a 30-minute immersion in the aldehyde mixture was optimum. After the sublingual gland was removed, the submandibular gland was softly struck with forceps having rounded tips, then shaken in fixative or buffer. The tissue that remained was postfixed in osmium tetroxide. This method results in the complete divestment of nonductular parenchyma from the rat submandibular gland, leaving the duct system clean and ready for microscopic examination.  相似文献   

6.
OBJECTIVE: To present two cases of probable lymphoepithelial cysts of the submandibular glands in patients who were human immunodeficiency virus (HIV) positive and who also had lymphoepithelial cysts of the parotid glands. MATERIALS AND METHODS: Computed tomography and MRI of two HIV positive patients with lymphoepithelial cysts of the parotid glands and cysts in the submandibular glands were correlated with the histories and the possible presence of other known causes of submandibular gland multiple cysts. RESULTS: Because of the present treatment philosophy regarding HIV positive patients with major salivary gland cysts, surgical resection of these glands was not performed. All other known causes of multiple submandibular gland cysts were excluded by either history or laboratory data. CONCLUSION: Computed tomography and MRI on two patients with known HIV infection and bilateral parotid lymphoepithelial cysts are presented. Both patients also had bilateral multiple submandibular gland cysts and no evidence of obstructive glandular disease, autoimmune disease, or other organ system cysts. These cases of presumed submandibular gland lymphoepithelial cysts are rare in the literature. They are presented in the hope that other radiologists will be stimulated to document the occurrence of this entity.  相似文献   

7.
Nerve growth factor (NGF) is a protein highly expressed in the male mouse submandibular gland. We have applied a non-radioactive in situ hybridization method using digoxigenin-labeled NGF oligonucleotides, and have found the highest amounts of NGF mRNA in the secretory striated ducts of the male mouse submandibular gland. Scattered strongly positive cells were found in male mouse sublingual glands. Weakly labeled cells were seen in female mouse and in male rat submandibular gland striated duct cells. Using 33P as an alternative to 32P and 35S, we demonstrated a 1.3 KB NGF mRNA in salivary glands of male mice by Northern blot hybridization. Using 33P we detected NGF mRNA in male mouse submandibular glands by in situ hybridization but with a signal that, compared with the non-radioactive method, had a very low resolution. Castration of male mice almost abolished both the 1.3 KB NGF mRNA seen with Northern blots and the NGF mRNA labeling in submandibular glands 4 weeks after the operation, whereas levels were increased 6 hr and 2 days after sympathectomy. We conclude that hybridization with digoxigenin-labeled NGF oligonucleotides is a good tool to study the expression and regulation of NGF mRNA in male mouse submandibular glands.  相似文献   

8.
BACKGROUND: Collection of saliva produced by the major salivary glands may be accomplished either by cannulation of the glandular ducts or by the application of specific collecting devices to the emergence area of the glandular ducts. Those procedures are complex, slow, invasive and require skilled personnel. AIM: To report the design and application of a device to collect parotid saliva (snail collector) and another device to collect saliva from the submandibular/sublingual complex. MATERIAL AND METHODS: The saliva collection devices were tested in 40 healthy volunteers (20 male) aged 18 to 22 years old. Saliva was collected using conventional conditions, during 5 to 15 min. RESULTS: An average of 1 to 1.5 ml of saliva was collected in the 10-15 min period from both parotid and submandibular/sublingual glands. Flow rates from parotid glands were 80 microliters/min and 180 microliters/min from submandibular/sublingual glands. Parotid saliva had a protein and organic material concentration twice as high than saliva from submandibular/sublingual glands. The presence of human alpha-amylase duplet (Mr 55 kD and 58 kD) predominated in parotid saliva, whereas saliva from submandibular/sublingual glands had other molecular markers such as the lysozyme duplet (Mr 18.5 kD and 17 kD). CONCLUSIONS: The tested devices were easily applicable, comfortable and allowed the collection of both parotid saliva and submandibular/sublingual saliva from various subjects at once, under the supervision of a single professional.  相似文献   

9.
Of all head and neck neoplasms, 3% are malignant salivary neoplasms. Only 20% of them affect submandibular glands. These tumours vary histologically, which results from the complex embryogenesis of the glands. Malignant submandibular gland tumours are twice as frequent as parotid gland tumours. Simultaneous occurrence of quite different malignant tumours in the same salivary gland is extremely rare. The age range of patients affected with salivary gland neoplasms is wide. However, the occurrence of these neoplasms in children is exceptionally rare. The authors describe a case of a 13-year-old girl with acinose adenoid carcinoma and cystiscarcinoma coexisting in one submandibular salivary gland.  相似文献   

10.
Gross cystic disease fluid protein-15 (GCDFP-15)/prolactin-inducible protein (PIP) is present at moderate levels in human submandibular and sublingual glands and is barely detectable in human parotid gland. The rodent homologue, PIP, has previously been identified in adult submandibular and lacrimal glands. Here we present the molecular characterization of rat PIP and show that this protein is a product of neonatal and adult rat submandibular, sublingual, and parotid glands. cDNA clones encoding rat PIP were isolated and sequenced. The deduced amino acid sequence of rat PIP shows 56% overall identity and 80% similarity with mouse PIP. By SDS-PAGE, secreted rat PIP has an apparent Mr of 17,000, with a minor proportion present as Mr 20-22,000 N-glycosylated forms. PIP was localized in rat salivary glands by immunogold silver staining. PIP was identified in acinar cells of developing and mature submandibular and parotid glands and at very low levels in sublingual gland serous demilunes. Typically, rat submandibular gland secretory proteins are produced by either acinar cell progenitors (Type III cells) or mature acinar cells. The expression pattern observed for PIP is similar to that previously reported for salivary peroxidase, an important component of nonimmune mucosal defense.  相似文献   

11.
Rats secrete saliva in response to heat. In the present study, details of thermal salivation were investigated using the FOK rat in comparison with Sprague-Dawley (SD), Donryu, and ACI rats. The FOK rat is a strain inbred for genotypic heat adaptation and endures heat for long periods. Conscious rats of all four strains were exposed to 42.5 degrees C. The order of heat endurance times at this temperature was FOK > SD > Donryu = ACI. FOK rats spread their saliva over their entire ventral surface, their faces, and their outside legs. This saliva area was wider than those made by the other three strains. SD rats spread in an area wider than those of the Donryu and ACI rats. Saliva spreading in the FOK rats continued for 4.0-4.5 h, far longer than in the other strains. Under ketamine anesthesia and exposure to 40 degrees C, the FOK rats secreted saliva at 1390+/-235 microL/100 g of body weight during a 60-min observation period. This was the highest rate among the four rat strains (p < 0.0001). The body temperature increase rate in anesthetized FOK and SD rats was lower than in the other two strains, suggesting a minor contribution of unknown factors. Ligation of the submandibular gland ducts abolished the thermal salivation of the FOK rats, whereas ligation of the parotid duct had no effect. The submandibular, sublingual, and lachrymal glands in the FOK rats were 1.3-1.5, 1.25-1.4, and 1.3-1.5 times heavier, respectively, than those in the other three strains, whereas the parotid gland of the FOK rats was not enlarged. These findings indicate that the rats' saliva spreading and ET values are significantly correlated. A potentiated and long-lasting salivation from the submandibular gland was acquired during development of genotypic heat adaptation. This salivation is actuated in response to heat. The pronounced thermal salivation is probably attributable to adaptive changes in the superior salivatory nucleus-chorda tympani-submandibular gland pathway.  相似文献   

12.
Glycoprotein secretion in the mouse submandibular gland was investigated by light microscope radioautography of semi-thin sections after the administration of L-3H-fucose. The incorporation of the precursor in the acini was negligible. 3H-fucose was taken up in the paranuclear region of the cells lining the intercalated, secretory, striated and excretory ducts. This labeling pattern was interpredted as addition of the precursor to glycoproteins within the Golgi apparatus. Incoropration in the intercalated duct was restricted to the cells with fine cytoplasmic granules. The glycoproteins synthesized by the intercalated and secretory ducts were transported to the saliva by the secretion granules. It is assumed that the glycoproteins synthesized in the striated and excretory ducts are plasma membrane glycoproteins which seem to renew continuously. Quantitation of the radioautographs supplied data concerning the incorporation of 3H-fucose into newly synthesized glycoproteins as well as the renewal of the labeled macromolecules in each duct.  相似文献   

13.
Cytoplasmic crystalloids are abundant in the excretory ducts of the accessory submandibular gland of the long-winged bat, Miniopterus magnator. The crystalloids, which always lack a membranous enclosure, may have an intricate silhouette. They consist of parallel linear densities with a 12.5 nm periodicity. These densities actually may be thin-walled tubules. In some crystalloids, intersecting subcrystalloids produce a complex pattern of decussate densities. In a few rare instances, continuities were detected between a crystalloid and a smooth-surfaced cisternal element. In other mammalian species, similar crystalloids connected to smooth endoplasmic reticulum play a role in steroid metabolism. We postulate that the ductular crystalloids in M. magnator might be involved in production of a factor that influences mating behavior.  相似文献   

14.
Tuft cells, a widespread cell type that is present in the mucosal epithelia of hollow organs, including the main excretory duct (MED) epithelia of the rat salivary gland, are well documented morphologically. However, studies of their development are few. The purpose of the present study was to examine the perinatal and postnatal development of tuft cells in the main excretory duct of the rat submandibular gland. Main excretory ducts of the submandibular gland were obtained from five male Wistar rats at the ages of 0, 1, 7, 14, 17, 21, 23, 28, and 56 postnatal days and were prepared for scanning and transmission electron microscopy. The tuft cells, which are distinguished easily by their long microvilli protruding into the lumen, were recognizable first at 17 postnatal days. They showed a remarkable increase in number between 3 and 4 postnatal weeks. The percentages of tuft cells were 0.4% at 17 postnatal days and 0.8% at 3 postnatal weeks. The number of tuft cells represented approximately 5% of the total epithelial cells by 4 postnatal weeks. There was a significant difference between 3 and 4 postnatal weeks (P < 0.01). The microvilli of the tuft cells at the time of weaning had almost the same width as in the adult, but they were shorter. Microfilaments extending from the tips of the microvilli and microtubules and many electron-lucent vesicles in the supranuclear cytoplasm also were observed. These results indicate that tuft cells appeared in the MED of the submandibular gland during weaning and had abundant vesicles in their apical cytoplasm.  相似文献   

15.
PURPOSE: To show that the rhytidectomy approach without a submandibular limb can be successfully used for excision of buccal space tumors and how this technique allows reconstruction of the contour defect associated with tumor extirpation by utilization of the superficial musculoaponeurotic system (SMAS) interposition. PATIENTS AND METHODS: Five cases of buccal space tumors are presented: two accessory lobe of parotid tumors, one parotid duct cyst, one nodular fasciitis of anterior masseter, and one lymphoma. RESULTS: Rhytidectomy approach without a submandibular limb incision afforded adequate exposure to the tumors with excellent cosmetic results. Furthermore, SMAS interposition, which was allowed through this technique, ameliorated the contour defect created. CONCLUSION: Rhytidectomy approach with SMAS interposition is effective for management of buccal space tumors.  相似文献   

16.
The mechanism(s) of radiation-induced salivary gland dysfunction is poorly understood. In the present study, we have assessed the secretory function (muscarinic agonist-stimulated saliva flow, intracellular calcium mobilization, Na+/K+/2Cl- cotransport activity) in rat submandibular glands 12 months postirradiation (single dose, 10 Gy). The morphological status of glands from control and irradiated rats was also determined. Pilocarpine-stimulated salivary flow was decreased by 67% at 12 months (but not at 3 months) after irradiation. This was associated with a 47% decrease in the wet weight of the irradiated glands. Histological and morphometric analysis demonstrated that acinar cells were smaller and occupied relatively less volume and convoluted granular tubules were smaller but occupied the same relative volume, while intercalated and striated ducts maintained their size but occupied a greater relative volume in submandibular glands from irradiated compared to control animals. In addition, no inflammation or fibrosis was observed in the irradiated tissues. Carbachol- or thapsigargin-stimulated mobilization of Ca2+ was similar in dispersed submandibular gland cells from control and irradiated animals. Further, [Ca2+]i imaging of individual ducts and acini from control and irradiated groups showed, for the first time, that mobilization of Ca2+ in either cell type was not altered by the radiation treatment. The carbachol-stimulated, bumetanide-sensitive component of the Na+/K+/ 2Cl- cotransport activity was also similar in submandibular gland cells from control and irradiated animals. These data demonstrate that a single dose of gamma radiation induces a progressive loss of submandibular gland tissue and function. This loss of salivary flow is not due to chronic inflammation or fibrosis of the gland or an alteration in the neurotransmitter signaling mechanism in the acinar or ductal cells. The radiation-induced decrease in fluid secretion appears to be related to a change in either the water-handling capacity of the acini or the number of acinar cells in the gland.  相似文献   

17.
The effect of orally feeding 15000 I.U. of vitamin A during 15 days to male rats of the Wistar strain was studied on the sialic acid and hexosamine contents of the salivary glands. Sialic acid and hexosamine contents in the submandibular and sublingual salivary glands showed a decrease while those for the parotid salivary gland did not alter.  相似文献   

18.
Gene delivery into rat submandibular gland in vivo by direct intracapsular injection has been studied. After the administration of adenovirus constructs, Ad-RSV-LacZ and Ad-CMV-LacZ, beta-galactosidase expression was localized in the granular convoluted tubular and striated duct cells of rat submandibular gland by in situ enzyme histochemistry. Adenovirus-mediated delivery of the human kallistatin gene (Ad-RSV-HKBP) into rat submandibular gland results in the expression of human kallistatin in a time-dependent manner. The expression of immunoreactive kallistatin in submandibular gland was detected 1 day after the Ad-RSV-HKBP injection and it reached a plateau (1-2 ng/mg protein) 2 days after gene delivery. Higher levels of human kallistatin were found in the submandibular gland of 6-month-old rats than in one-month-old rats. After direct gene injection, human kallistatin was localized mainly in cells of the granular convoluted tubules and striated ducts of rat submandibular gland using a specific monoclonal antibody to human kallistatin. The results indicate that direct intracapsular gene delivery into the submandibular gland provides a simple and reliable method for introducing foreign genes into the gland. This method can be used for studying gene regulation in vivo and may have potential for gene therapy in oral diseases.  相似文献   

19.
Primary malignant lymphomas of the major salivary glands are rare and usually arise in the parotid gland (2% of all neoplastic disorders). In this report clinical records of 28 cases of NHL of salivary glands (27 in the parotid gland and one in the submandibular gland) are reviewed and problems related to diagnosis and management strategies are discussed. The 5-year overall survival rate was 72% and did non differ from the survival of other NHL of the head and neck. Statistical evaluation of prognostic factors (age, histology, clinical stage, grading, bulky and surgical approach--biopsy versus parotidectomy), are presented. Analysis of these factors showed that prognosis was not influenced by age, histology, clinical stage and grading of disease. Poor survival was significantly correlated to bulky lesions (tumor size greater than 6 cm). In our experience surgical treatment did not significantly affect survival rate. It is concluded that diagnostic surgical procedures in case of suspected NHL of the parotid gland are fine needle aspiration biopsy. (FNAB) or incisional biopsy. The treatment of choice is radiotherapy associated with chemiotherapy in cases of localized-bulky or disseminated disease.  相似文献   

20.
The influence of parasympathetic and sympathetic nerves on the parotid gland of the rat was investigated. It was found that both divisions of the autonomic nerves evoke secretion and probably also motor effects in this gland. Secretion elicited on sympathetic stimulation was mediated both via alpha- and beta-adrenoceptors, while motor effects were mediated via alpha-adrenoceptors. On stimulation of the autonomic nerves a lower duct pressure was reached in the parotid than in the submaxillary gland, and on sympathetic nerve stimulation the flow of saliva always started later from the parotid than the submaxillary gland. These findings are discussed in the view of the different arrangement of the myoepithelial cells in the 2 glands.  相似文献   

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