OBJECTIVETo evaluate the thickness and viscoelasticity of whole saliva (WS), parotid saliva (PS) and submandibular/sublingual gland saliva (SMSLS) film adsorption on the hydroxyapatite (HA) surface.

METHODSUltra-thin layer of HA nanocrystals was coated on the dissipation TiO(2) sensor of gold quartz crystal microbalance using electrophoretic deposition technique. The thickness of the HA layer was measured by the ellipsometer, and element analysis was conducted using X-ray photoelectron spectroscopy. Atomic force microscopy and scanning electron microscope were used to observe its morphology. The in-situ adsorption thickness, the shear elastic modulus and the shear viscosity of salivary layers (WS, PS and SMSLS) on HA surfaces were investigated. The statistical data were analysed by an one-way ANOVA analysis followed by a SNK-q test.

RESULTSThe results show that the HA layer was a plate-like morphology with 1.53 ± 0.12 in Ca/P molar ratio, (19.1 ± 0.9) nm in the thickness and (6.5 ± 1.6) nm in the roughness. The thickness of salivary film was SMSLS [(21.84 ± 1.25) nm] > WS[(17.91 ± 1.35) nm] > PS [(14.30 ± 1.03 nm) (P < 0.05). The shear elastic modulus of salivary film was PS [(0.61 ± 0.01) MPa] > SMSLS [(0.31 ± 0.09) MPa] and WS [(0.25 ± 0.03) MPa] (P < 0.05). The trend of the shear viscosity was opposite to one of thickness.

CONCLUSIONSThe characteristics of saliva adsorption on HA surface suggest that the thicker, softer and more hydrated properties for the SMSLS and WS films are likely to afford a stronger lubrication to protect oral surfaces from wear and dehydration. The viscoelasticity of the PS film is probably related to the retention covering the oral cavity.

Adsorption ; Adult ; Durapatite ; chemistry ; Female ; Humans ; Male ; Microscopy, Atomic Force ; Parotid Gland ; secretion ; Photoelectron Spectroscopy ; Quartz Crystal Microbalance Techniques ; Saliva ; chemistry ; Sublingual Gland ; secretion ; Submandibular Gland ; secretion ; Surface Properties ; Viscosity ; Young Adult

OBJECTIVETo observe the effect of bilateral parotid gland atrophy on the whole saliva flow rate and the growth of main oral pathogens in different sites of oral cavity.

METHODSTen healthy miniature pigs were divided into two groups. The parotid glands of test group (n = 5) were bilaterally ablated by methyl violet. Another healthy five miniature pigs served as the control group. Whole saliva was collected and the whole saliva flow rate detected in both groups at 12 and 24 months respectively after parotid atrophy. The total numbers of oral main pathogens in the first molar, cuspid sub-gingival bacteria plaque and whole saliva were also detected.

RESULTSThe whole saliva flow rate was significantly decreased at both 12 and 24 months respectively after atrophy of bilateral parotid gland in miniature pig. Pathogens including Streptococcus mutans, Porphyromonas gingivalis and Fusobacterium nucleatum in different sites oral cavity were increased after bilateral parotid gland atrophy.

CONCLUSIONSBilateral ablation of the parotid glands led to a significant decrease of whole saliva flow rate. The total numbers of main oral pathogens were increased in different sites of oral cavity.

Animals ; Atrophy ; Disease Models, Animal ; Mouth ; microbiology ; Parotid Gland ; pathology ; Random Allocation ; Saliva ; secretion ; Swine ; Swine, Miniature

Synaptotagmin is a Ca2+ sensing protein, which triggers a fusion of synaptic vesicles in neuronal transmission. Little is known regarding the expression of Ca2+ - dependent synaptotagmin isoforms and their contribution to the release of secretory vesicles in mouse and rat parotid acinar cells. We investigated a type of Ca2+ - dependent synaptotagmin and Ca2+ signaling in both rat and mouse parotid acinar cells using RT-PCR, microfluorometry, and amylase assay. Mouse parotid acinar cells exhibited much more sensitive amylase release in response to muscarinic stimulation than did rat parotid acinar cells. However, transient [Ca2+]i increases and Ca2+ influx in response to muscarinic stimulation in both cells were identical, suggesting that the expression or activity of the Ca2+ sensing proteins is different. Seven Ca2+ - dependent synaptotagmins, from 1 to 7, were expressed in the mouse parotid acinar cells. However, in the rat parotid acinar cells, only synaptotagmins 1, 3, 4 and 7 were expressed. These results indicate that the expression of Ca2+ - dependent synaptotagmins may contribute to the release of secretory vesicles in parotid acinar cells.
Synaptotagmins/*metabolism ; Signal Transduction ; Rats ; Protein Isoforms/metabolism ; Parotid Gland/cytology/*metabolism ; Muscarinic Agonists/pharmacology ; Mice ; Exocytosis/drug effects/physiology ; Carbachol/pharmacology ; Calcium/metabolism/*physiology ; Animals ; Amylases/secretion

Sialadenosis is a unique form of non-inflammatory, non-neoplastic bilateral salivary gland disorder characterized by recurrent painless swelling which usually occurs in parotid glands. Alcoholism is one of the main causes of sialadenosis along with diabetes, bulimia, and other idiopathic causes. The prognosis is verified according to the degree of liver function. We present a case of a 46 year-old man who had alcoholic fatty liver disease diagnosed as alcoholic sialadenosis based on clinical points of recurrent bilateral parotid swelling after heavy alcohol drinking, computed tomography, and fine-needle aspiration biopsy. After stopping alcohol drinking and treated with conservative treatment, he got improved without specific sequela.
Adult ; *Alcohol Drinking ; Fatty Liver, Alcoholic/*diagnosis/etiology/radiography ; Humans ; Male ; Parotid Gland/*radiography/secretion ; Positron-Emission Tomography ; Sialadenitis/*diagnosis/etiology ; Tomography, X-Ray Computed

Whole gland perfusion technique was applied to rat parotid glands to assess whether amylase affects fluid secretion. Control perfusion without any secretagogue evoked no spontaneous secretion. Carbachol (CCh 1 microM) induced both amylase and fluid secretion with distinctive kinetics. Fluid secretion occurred constantly around 60 microL/g-min, whereas amylase secretion exhibited an initial peak, followed by a rapid decrease to reach a plateau. Isoproterenol (Isop 1 microM) alone did not induce fluid secretion although it evoked amylase secretion as measured in isolated perfused acini. Addition of Isop during CCh stimulation evoked a rapid and large rise in amylase secretion accompanied by small increase in oxygen consumption. Morphological observations carried out by HR SEM and TEM revealed exocytotic profiles following Isop stimulation. CCh stimulation alone seldom showed exocytotic profiles, suggesting a low incidence of amylase secretion during copious fluid secretion. Combined stimulation of CCh and Isop induced both vacuolation and exocytosis along intercellular canaliculi. These findings suggest that control of salivary fluid secretion is independent of the amylase secretion system induced by CCh and/or Isop.
Amylases/metabolism* ; Animal ; Carbachol/pharmacology ; Cholinergic Agonists/pharmacology ; In Vitro ; Isoproterenol/pharmacology ; Male ; Microscopy, Electron ; Microscopy, Electron, Scanning ; Oxygen Consumption/physiology ; Oxygen Consumption/drug effects ; Parotid Gland/ultrastructure ; Parotid Gland/secretion* ; Parotid Gland/enzymology* ; Perfusion ; Rats ; Rats, Wistar ; Saliva/metabolism* ; Sympathomimetics/pharmacology