• Journal of the korean academy of Pediatric Dentistry
• /
• v.26 no.2
• /
• pp.399-415
• /
• 1999

From bacteria to mammalian cells, one of the most important mediators of intracellular signal transduction mechanisms which regulate a variety of intracellular processes is free calcium. In salivary acinar cells, elevation of intracellular calcium concentration ($[Ca^{2+}]_i$) is essential for the salivary secretion induced by parasympathetic stimulation. However, in addition to $[Ca^{2+}]_i$, gap junctions which couple individual cells electrically and chemically have also been reported to regulate enzyme secretion in pancreatic acinar cells. Since the plasma membrane of salivary acinar cells has a high density of gap junctions, and these cells are electrically and chemically coupled with each other, gap junctions may modulate the secretory function of salivary glands. In this respect, I planned to investigate the role of gap junctions in the modulation of salivary secretion and $[Ca^{2+}]_i$, using mandibular salivary glands of rats. In order to measure the salivary flow rate, fluid was collected from the cannulated duct of the isolated perfused rat mandibular glands at 2 min intervals. $[Ca^{2+}]_i$, was measured from the cells loaded with fura-2 by spectrofluorometry. The results obtained were as follows: 1. CCh-induced salivary secretion was reversibly inhibited by 1 mM octanol, a gap junction blocker. 2. CCh-induced increase in $[Ca^{2+}]_i$, was also reversed by the application of 1 mM octanol. 3. Octanol did not block the initial increase in $[Ca^{2+}]_i$ caused by CCh, which suggested that the reduction of $[Ca^{2+}]_i$, caused by gap junction blockade was not resulted from the inhibition of $Ca^{2+}$ release from intracellular $Ca^{2+}$ stores. 4. Addition of octanol during stimulation with $1{\mu}M$ thapsigargin, a potent microsomal ATPase inhibitor, reduced $[Ca^{2+}]_i$, to the basal level. This suggested that inhibition of gap junction permeability closed plasma membrane $Ca^{2+}$ channels. 5. 2,5-di-tert-butyl-1,4-benzohydroquinone (TBQ) generated $[Ca^{2+}]_i$ oscillations resulting from periodic influx of $Ca^{2+}$ via plasma membrane. The TBQ-induced $[Ca^{2+}]_i$ oscillations were stopped by the application of 1mM octanol which implicated that gap junctions modulate the permeability of plasma membrane $Ca^{2+}$ channels. 6. Glycyrrhetinic acid, another well known gap junction blocker, also inhibited CCh-induced salivary secretion from rat mandibular glands. These results suggested that gap junctions play an important role in the modulation of fluid secretion from the rat mandibular glands and this was probably due to the inhibition of $Ca^{2+}$ influx through the plasma membrane $Ca^{2+}$ channels.

• Journal of Oral Medicine and Pain
• /
• v.25 no.4
• /
• pp.345-353
• /
• 2000

This study was to investigate normal salivary flow rates and normal indices of Quantitative analysis of salivary scintigraphy. 96 adult volunteers were studied by Questionnaire evaluating salivary conditions and clinical examinations. 35(male 23, female 12, age range 23-31years) that absented subjective and objective symptoms related saliva were classified as normal group. The normal group underwent measurement unstimulated and stimulated salivary flow rates and salivary scintigraphy. The obtained results were as follows: 1. There were not significant in sex differences of unstimulated and stimulated salivary flow rates. The unstimulated salivary flow rate was $0.66{\pm}0.41g/min$, stimulated salivary flow rates was $1.61{\pm}0.69g/min$. 2. As comparing of parameters of salivary scintigraphy, the Uptake ratio(UR), $T_{max}$, $T_{min}$, Maximum accumulation (MA), Maximum secretion(MS) of parotid and submandibular glands were not significant in sex and side-ralated differences. 3. The UR, $T_{max}$, MA, MS of parotid gland were significantly higher than those of submandibular gland; in the parotid gland, UR, $3.67{\pm}0.88$, $T_{max}$, $18.77{\pm}0.43min$, MA, $41.35{\pm}9.22%$, MS, $43.13{\pm}9.13%$; in the submandibular gland, UR, $3.04{\pm}0.10$, $T_{max}$, $18.48{\pm}0.52min$, MA, $36.47{\pm}14.18%$, MS, $36.88{\pm}12.20%$. 4. As classifying of time-activity curve, the most of parotid gland was N-type(97.1%), submandibular gland was observed in order of M-type(67.1%), N-type(21.4%), F-type(11.4%), however, was not observed S-type. 5. As the type of time-activity curve of submandibular gland was more flattened, the UR, $T_{max}$, MA, MS were significantly decresed.

• Microbiology and Biotechnology Letters
• /
• v.31 no.1
• /
• pp.36-41
• /
• 2003

In order to increase the production and secretion rate of mouse salivary $\alpha$-amylase from Saccharomyces cerevisiae, various experiments were attempted. A plasmid pCNNinv (AMY) was constructed by the substitution of ADCl promoter and native signal sequence of mouse salivary $\alpha$-amylase cDNA gene with PRBI promoter and yeast invertase leader sequence, which resulted in 25% increase in the production of $\alpha$-amylase in the culture medium. The respiratory deficient transformant carrying pCNNinv (AMY) were obtained by treating yeast cells with ethidium bromide, and the $\alpha$-amylase activities in the culture brothes of the respiratory-deficient transformants were 5-8 times higher than that of parental wild type strain. $\alpha$-Amylase activity was also increased 3 times when the 0.015% (w/v) of 2-mercaptoethanol was added to the culture medium.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.37 no.3
• /
• pp.352-358
• /
• 2010

Chemotherapy or radiotherapy used for the treatment of pediatric cancer may have many adverse effects on the oral cavity. Oral mucositis, reduced salivary flow, oral infection, hypodontia, microdontia, arrested root development, and enamel hypoplasia are common oral complications. The aim of this study is to evaluate the effects of cancer therapy on dental caries activities. The children who had been treated for neuroblastoma in the department of pediatrics, Samsung Medical Center, were included and healthy children served as controls. The salivary flow rate, salivary buffering capacity, and Streptococcus mutans counts of both groups were evaluated using Dentocult$^{(R)}$ SM and Dentobuff$^{(R)}$ Strip. The dental caries activity related to the age at the start of treatment and the time elapsed since treatment completion were also evaluated. As a result, neuroblastoma patients had significantly lower salivary flow rate than the controls, while there were no significant differences between two groups as for salivary buffering capacity and Streptococcus mutans counts. The dental caries activities related to the age at the start of treatment and the time elapsed since treatment completion were not significantly different.

• Journal of Oral Medicine and Pain
• /
• v.42 no.3
• /
• pp.62-71
• /
• 2017

Purpose: The purpose of this study was to examine the rate of salivation before and after olfactory stimulation using BPO (black pepper oil) and then, to collect basic data for screening the possibility of introducing olfactory stimulus to prevent and improve dry mouth. Methods: The subjects in this study were 60 college students in Jeon-Nam province. The subjects were randomly divided into 3 groups; the BPO group (n=20), the lavender oil (LVO) group (n=20), and the distilled water (DW) group (n=20). The amount of whole saliva before and after olfactory stimulation was measured 14 times for a 4-week period. Results: In the BPO and LVO groups, the amount of whole saliva increased after the olfactory stimulation and it was most prominent in the BPO group (p<0.05). The difference of whole salivation was higher in the BPO group (p<0.05) and there was no significant difference in the salivary flow rate in the DW group. After 14 times of measurement for 4 weeks, the BPO and LVO groups showed an increase in salivary rate at an early stage compared without stimulation (p<0.05), but there was no significant difference between the 2 groups in the middle. Since the twelfth measurement, whole saliva secretion increased and maintained the elevated level (p<0.05). Conclusions: The olfactory stimulation using BPO may contribute to stimulating salivation. Further studies are needed for subjects with dry mouth symptoms. In the future, qualitative and quantitative studies should be conducted for people who complains about oral dryness.

• Journal of Korean society of Dental Hygiene
• /
• v.16 no.3
• /
• pp.463-469
• /
• 2016

Objectives: The purpose of the study is to investigate the effect of chewing gum containing Prunus mume extract(PME) on the change of saliva ingredients. On the basis of the biological background of molecules and diagnostic indices in the use of saliva, the mastication effect of chewing gum containing PME was demonstrated in terms of secretory IgA concentration and total protein concentration in stimulated saliva. Methods: This study is an experimental research on the use of a research design before and after applying a randomized control group. Participants were distributed randomly to the experimental group and the control group, respectively. The experiment group was instructed to masticate the chewing gum containing PME for 10 minutes for one month after each meal within 30 minutes. Salivary secretion was collected by the participants between 8 and 10 a.m in the morning in the research office. For the measurement of secretory IgA and total protein concentrations in the saliva, indirect enzyme-linked immunosorbent assay(ELISA) was used. Results: The salivation stimulation rate was significantly increased after four weeks of masticating chewing gum containing PME after each meal(p<0.001). Mastication of chewing gum containing PME for four weeks decreased the concentration of secretory IgA much more significantly than that after mastication for one week(p=0.003). The concentration of total protein in the saliva was decreased after four weeks in the experimental and control groups. Conclusions: Mastication of chewing gum containing PME stimulated salivary secretion and led to oral disease prevention in patients with xerostomia. Furthermore, it seems to be urgent to seek measures that can be utilized in intervention for patients with xerostomia.

• The Korean Journal of Nuclear Medicine
• /
• v.35 no.1
• /
• pp.43-51
• /
• 2001

Purpose: In this study, we compared the quantitative characteristics of dynamic salivary gland scintigraphy with static scintigraphy in patients with clinical sicca syndrome using Tc-99m pertechnetate. Materials and Methods: Fifty-two parotid glands and 52 submandibular glands out of 26 patients with clinical sicca syndrome were studied by dynamic and static salivary gland scintigraphy. Ten normal volunteers were also studied as a control group for comparison of scintigraphic parameters. Ten minutes after injection of 370 MBq Tc-99m pertechnetate, we obtained pre-stimulus static images for a few minutes. Then dynamic salivary gland scintigraphy with lemon juice stimulation was performed for 20 minutes. Finally we obtained post-stimulus static images after dynamic images. On dynamic study, functional parameters such as uptake rate, secretion rate and re-uptake rate were calculated. The results of dynamic study and static images were compared. Results: On dynamic study, we could obtain functional parameters of salivary glands successfully. On dynamic study, 22 parotid glands and 22 submandibular glands out of each of 52 glands are abnormal. The static images demonstrated somewhat different results, of which reasons we could assume via dynamic study. Conclusion: Dynamic salivary gland scintigraphy using Tc-99m perechnetate were more functional than static images and might be useful in the assessment of the functional change of the salivary gland in patients with clinical sicca syndrome.

• Journal of Korean society of Dental Hygiene
• /
• v.7 no.2
• /
• pp.167-176
• /
• 2007

Objectives: The purpose of this study was to investigate the dental caries activity of some commercial drinks. Methods : Acidity levels were recorded as pH values of original drinks and amount of 50%-sodium hydroxide(NaOH) required to neutralize by titration 50.00ml of the drink(It was called titratable acid). Acidity of the drinks with S. sobrinus was measured at an interval of one hour after incubating ($37^{\circ}C$) the test drinks and control solution which was composed 20.00ml of neutralized drinks as pH 7.0 with 0.2ml of a pooled suspension of S. sobrinus. Results : The drink with the highest pH value was the Cow's milk(pH $6.70{\pm}0.01$), and the most acidic was the Carbonated drink(pH $2.40{\pm}0.02$). The drink with the highest buffer effect was the Fruit juice($139.78{\pm}0.76$), and the lowest was the Glucose solution(control, $4.42{\pm}0.20$). The drinks with S. sobrinus during incubation at $37^{\circ}C$ for 24h were decreased to below critical pH 5.5. Spending times from pH 7.0 to pH 5.5~5.0 were Glucose solution(less than 1h). Carbonated drink(3h), Fruit juice(5h), Cow's milk(8h) and Mixed drink(21h). Conclusions: These results show that some commercial drinks with S. sorbrinus have the possibility of tooth decalcification. Thus, it is suggested that the people who have the low salivary secretion rate and the children who sleep without toothbrushing after drinking need the instruction for diet control and oral health education.