Understanding salivary fluid and protein secretion

Turner, R; Saito, Hiroshi

doi:10.1034/j.1601-0825.2002.10815.x

Cited by 225 publications

(185 citation statements)

References 55 publications

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“…Although significant, these relationships are not clear since values given after stimulation by citric acid at high flow are influencing strongly the relationships and F 60 s larger than 500μL were not achieved by other tastants. Mechanisms for secretion of proteins in parotid glands are discussed in full detail in review articles (Turner and Sugiya 2002;Gorr et al 2005) that generally support the notion that secretion is controlled by the autonomic nervous system. The sympathetic nervous system tends to evoke greater release of proteins and even higher when in synergy with the parasympathetic system (Proctor and Carpenter 2007).…”

Section: Taste and Proteinsmentioning

confidence: 97%

Effects of Different Tastants on Parotid Saliva Flow and Composition

et al. 2009

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Saliva from parotid glands plays a role in taste perception. Parotid saliva is also stimulated by tastants. The aim of this work is to investigate the effects of different tastants on the parotid salivary response in six subjects. Five tastants were given in different concentrations in solution and held in the mouth for 10 s. The flow rate, protein concentration, and pH of secreted parotid saliva were monitored continuously for 5 min. Stimulation by tastants on flow rate response consists of an immediate rise in flow followed by a plateau and a rapid return to prestimulus flow. Response of pH results in a slower increase while protein concentration consists in a slower decrease, both followed by a return to prestimulus levels in about 4 min. From a resting flow rate of about 140μL/min, an increase in flow rate to 370μL/min was caused by stimulation for 10 s with 10 mL of solutions of 0.01 M citric acid, 0.13 M MgSO 4 , 0.25 M monosodium glutamate, 0.5 M NaCl, or 0.5 M sucrose. Comparisons of the different tastants showed that the pH of stimulated parotid saliva increased linearly (r=0.9), irrespective of the nature of the tastant. Protein concentration decreased (r=−0.45) and protein amount increases (r=0.58) with increase in flow rate for all tastants. Corrected for the effects of flow rate, protein amount depended on the nature of the tastant with the greatest secretion after stimulation by citric acid. Flow rate was largely responsible for pH but tastant appears to play an additional role with flow rate on protein secretion.

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Section: Taste and Proteinsmentioning

confidence: 97%

Effects of Different Tastants on Parotid Saliva Flow and Composition

et al. 2009

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“…In this study, we investigated the effects of diamide on release of the digestive enzyme amylase by acinar cells of the rat parotid gland. In rat parotid acinar cells, the stimulation of β-adrenergic receptors activates adenylate cyclase via the heterotrimeric GTP-binding protein (G-protein) Gs, which leads to an increase in intracellular cAMP level, and consequently evokes the exocytotic release of amylase (22,30). The results demonstrate that thiol-oxidation by diamide reduces the release of amylase induced by β-adrenergic receptor activation in rat parotid acinar cells.…”

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confidence: 63%

Thiol-oxidation reduces the release of amylase induced by β-adrenergic receptor activation in rat parotid acinar cells

Guo

Satoh

et al. 2010

Biomed. Res.

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In parotid acinar cells, the activation of β-adrenergic receptors induces the accumulation of intracellular cAMP, and consequently provokes the exocytotic release of amylase, a digestive enzyme. The cellular redox status plays a pivotal role in regulating various cellular functions. Cellular redox imbalance caused by the oxidation of cellular antioxidants, as a result of oxidative stress, induces significant biological damage. In this study, we examined the effects of diamide, a thioloxidizing reagent, on amylase release by rat parotid acinar cells. In cells treated with diamide, the formation of cAMP and the release of amylase induced by the β-agonist isoproterenol (IPR) were partially reduced. The inhibitory effect of diamide on the IPR-induced release of amylase could be abrogated by reduced glutathione or dithiothreitol. Diamide had no effect on the amylase release induced by forskolin, an adenylate cyclase activator, or by mastoparan, a heterotrimeric GTPbinding protein activator. In cells treated with diamide, the binding affinity for [ 3 H]DHA, but not the number of binding sites, was reduced. These results suggest that β-adrenergic receptor function is reduced by thiol-oxidation, which inhibits amylase secretion by parotid acinar cells.Reactive oxygen species (ROS) play important roles as cell signaling molecules for normal biological processes. However, excessive generation of ROS and/or impairment of antioxidant defenses that protect cells provoke alterations in cellular homeostasis, oxidative stress, inflammation, aging and the pathogenesis of a variety of diseases such as cancer, asthma, pulmonary hypertension and retinopathy (2,8,12,16). Under conditions of oxidative stress, the thiols in cysteine residues within proteins are the most susceptible target among oxidant-sensitive molecules (4,11,27,32). Cysteine is present in the active sites of many proteins and in protein motifs that function in protein regulation and trafficking, cellular signaling, and control of gene expression (4, 11). Therefore, modifications to thiols in proteins potentially affect the protein functions, and the degree of disruption depends on the importance of the cysteine residue(s) in carrying out those functions. Diamide (diazenedicarboxylic acid bis (N,N'-diamethylamide)) is an oxidizing compound. Because diamide easily penetrates cell membranes and reacts quickly and specifically with intracellular thiols (both low-molecular-mass thiols and protein sulfhydryls) without producing free radicals or other ROS (6,13,23,24), this compound is conveniently used for studies of thiol-oxidation. In salivary glands, it has been supposed that ROS are involved in the impairment of functions caused by inflammation, drugs, ionizing irradiation and ag-

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“…It remains to be shown whether RPG cells are capable by themselves of generating an osmotic gradient and driving fluid secretion through the transferred AQP1 channels or whether further re-engineering would be required (e.g., insertion of Cl À entry or exit pathways). 14,15 Such re-engineering, at least for testing a prototype, could be achieved with AAV2 or AAV 5 vectors. Both vector serotypes convey considerable stability of transgene expression when used to transduce murine salivary duct cells.…”

Section: Discussionmentioning

confidence: 99%

“…12 These cells were apparently of ductal origin, and thus, are incapable of unidirectional fluid secretion. [13][14][15] A significant hurdle in developing this device is the choice of an appropriate model for testing a prototype in vivo, because conventional rodent models are too small for effective testing of the in situ placement and function of an artificial salivary gland. 16 In the present study, we used a non-human primate tissue, parotid glands from rhesus monkeys, as a cell source.…”

Section: Introduction Tmentioning

confidence: 99%

Re-engineering Primary Epithelial Cells from Rhesus Monkey Parotid Glands for Use in Developing an Artificial Salivary Gland

Tran¹,

Sugito²,

Dipasquale³

et al. 2006

Tissue Engineering

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There is no satisfactory conventional treatment for patients who experience irreversible salivary gland damage after therapeutic radiation for head and neck cancer or because of Sjögren's syndrome. Additionally, if most parenchyma is lost, these patients also are not candidates for evolving gene transfer strategies. To help such patients, several years ago we began to develop an artificial salivary gland. In the present study, we used a non-human primate tissue source, parotid glands from rhesus monkeys, to obtain potential autologous graft cells for development of a prototype device for in situ testing. Herein, we present 3 major findings. First, we show that primary cultures of rhesus parotid gland (RPG) cells are capable of attaining a polarized orientation, with Na + /K + -adenosine triphosphatase, zonula occludens-1, and claudin-1 distributed in specific domains appropriate for epithelial cells. Second, we show that RPG cells exhibit 2 essential epithelial functions required for graft cells in an artificial salivary gland device (i.e., an effective barrier to paracellular water flow and the generation of a moderate transepithelial electrical resistance). Third, we show that RPG cells can express functional water channels, capable of mediating directional fluid movement, after transduction by adenoviral and adeno-associated virus type 2 vectors. Together these results demonstrate that it is feasible to individually prepare RPG cells for eventual use in a prototype artificial salivary gland.

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Understanding salivary fluid and protein secretion

Cited by 225 publications

References 55 publications

Effects of Different Tastants on Parotid Saliva Flow and Composition

Effects of Different Tastants on Parotid Saliva Flow and Composition

Thiol-oxidation reduces the release of amylase induced by β-adrenergic receptor activation in rat parotid acinar cells

Re-engineering Primary Epithelial Cells from Rhesus Monkey Parotid Glands for Use in Developing an Artificial Salivary Gland

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