• Journal of Dental Rehabilitation and Applied Science
• /
• v.33 no.1
• /
• pp.34-41
• /
• 2017

Anticonvulsants, calcium channel blockers and immunosuppressants are representative drugs related with gingival enlargement. Clinical signs and symptoms caused by drug-induced gingival enlargment frequently appear within 1 to 3 months after medication. At initial stage, it is limited to attached gingiva but may extend coronally and interfere with esthetics, mastication and speech. Interproximal spaces are common beginning area and pathologic teeth migration could be occurred by the lesion. Withdrawal or substitution of medication would be the most effective treatment of drug-induced gingival enlargement. However, periodontal treatment and further supportive periodontal therapy should be provided where change in medication is impossible. The present study reports the cases which show the resolution of inflammation with spontaneous teeth migration without change in medication. In all cases discussed in this report could be efficiently managed with proper periodontal treatment and further supportive periodontal therapy.

• International Journal of Oral Biology
• /
• v.38 no.1
• /
• pp.13-19
• /
• 2013

Various voltage-gated $K^+$ currents were recently described in dorsal root ganglion (DRG) neurons. However, the characterization and diversity of voltage-gated $K^+$ currents have not been well studied in trigeminal root ganglion (TRG) neurons, which are similar to the DRG neurons in terms of physiological roles and anatomy. This study was aimed to investigate the characteristics and diversity of voltage-gated $K^+$ currents in acutely isolated TRG neurons of rat using whole cell patch clamp techniques. The first type (type I) had a rapid, transient outward current ($I_A$) with the largest current size having a slow inactivation rate and a sustained delayed rectifier outward current ($I_K$) that was small in size having a fast inactivation rate. The $I_A$ currents of this type were mostly blocked by TEA and 4-AP, K channel blockers whereas the $I_K$ current was inhibited by TEA but not by 4-AP. The second type had a large $I_A$ current with a slow inactivation rate and a medium size-sustained delayed $I_K$ current with a slow inactivation rate. In this second type (type II), the sensitivities of the $I_A$ or $I_K$ current by TEA and 4-AP were similar to those of the type I. The third type (type III) had a medium sized $I_A$ current with a fast inactivation rate and a large sustained $I_K$ current with the slow inactivation rate. In type III current, TEA decreased both $I_A$ and $I_K$ but 4-AP only blocked $I_A$ current. The fourth type (type IV) had a smallest $I_A$ with a fast inactivation rate and a large $I_K$ current with a slow inactivation rate. TEA or 4-AP similarly decreased the $I_A$ but the $I_K$ was only blocked by 4-AP. These findings suggest that at least four different voltage-gated $K^+$ currents in biophysical and pharmacological properties exist in the TRG neurons of rats.

• Journal of Plant Biology
• /
• v.38 no.2
• /
• pp.195-201
• /
• 1995

The present study was made of the effects of abscisic acid(ABA) and calcium ions on dark respiration in protoplasts isolated from the basal intercalary meristematic tissues of oat (Avena sativa L.) seedlings. The influences of calcium channel blockers diitiazem(DTZ), verapamil(VPM), and $LaCl_2$ and the calmodulin antagonist trifluoperazine(TFP) on protoplast respiration activities were also investigated in order to evaluate the possible involvement of calcium channels and calmodulin during the dark respiration. The ABA only caused an 21% inhibition of protoplast respiration at $10^{-6}\;M$, but the extent of inhibition was very low by calcium treatments in the absence of ABA. In the presence of $10^{-6}\;M$ ABA, however, this inhibition of respiration increased by the increment of calcium ions concentrations. Treatments of DTZ and VPM were all found to restore the calcium-dependent inhibition of protoplast respiration by ABA and it was the same in thc $LaCl_2$ treatment except at $10^{-4}\;M$. At concentration from $10^{-6}\;M\;to\;10^{-4}\;M$, TFP also restored an inhibition of respiration. These results support the possibility that ABA increases plasmalemma permeability to calcium ions which might then bind to calmodulin to regulate oat protoplast dark respiration.ration.

• The Korean Journal of Physiology
• /
• v.26 no.1
• /
• pp.55-68
• /
• 1992

The effects of changes in extracellular $Na^+\;and\;Ca^+$ concentration on the membrane potential and contractility were studied in the antral circular muscle of guinea pig stomach in order to elucidate the existence and the nature of $Na^+/Ca^{2+}$ exchange mechanism. All experiments were performed in tris buffered Tyrode solution which was aerated with 100% $O_2$ and kept at $35^{\circ}C.$ The treatment of $10^{-5}$ ouabain was performed to induce intracellular $Na^+$ loading prior to the start of experiment. The results were as follows: 1. $Na^+$-free Tyrode or high $Ca^{2+}$-Tyrode solution hyperpolarized the membrane potential and induced contracture. The time course of contracture was similar to that of change in membrane potential. 2. The degree of hyperpolarization and the amplitude of contracture decreased in accordance with the increase of extracellular $Na^+$ concentration. 3. $Na^+$-free contracture was developed even after blocking the influence of intrinsic nerves by the pretreatment with atropine, guanethidine and TTX. 4. $Ca^{2+}$-channel blockers(D-600 or $Mn^{2+}$) and the blocker of intracellular $Ca^{2+}$ release from sarcoplasmic reticulum(ryanodine) did not suppress the development of $Na^+$-free contracture. And also, dinitrophenol had no effect on $Na^+$-free contracture. 5. Dose-response relationship between extracellular $Na^+$ concentrations and the magnitude of contractures showed a sigmoid pattern. The slope of straight line from Hill plot was 2.7. 6. In parallel with the increase of extracellular $Ca^{2+}$ concentration, the amplitude of contracture increased dose dependently and was maximum at 8 mM $Ca^{2+}$-Tyrode solution. 7. The relationship between extracellular $Ca^{2+}$ concentrations and the magnitude of contractures showed hyperbolic pattern. The slope of straight line from Hill plot was 1.1. From the above results, it is suggested that $Na^+/Ca^{2+}$ exchange mechanism exists in the antral circular muscle of guinea pig stomach and this mechanism affects the membrane potential electrogenically.

• The Korean Journal of Physiology and Pharmacology
• /
• v.19 no.3
• /
• pp.249-255
• /
• 2015

Wnk kinase maintains cell volume, regulating various transporters such as sodium-chloride cotransporter, potassium-chloride cotransporter, and sodium-potassium-chloride cotransporter 1 (NKCC1) through the phosphorylation of oxidative stress responsive kinase 1 (OSR1) and STE20/SPS1-related proline/alanine-rich kinase (SPAK). However, the activating mechanism of Wnk kinase in specific tissues and specific conditions is broadly unclear. In the present study, we used a human salivary gland (HSG) cell line as a model and showed that $Ca^{2+}$ may have a role in regulating Wnk kinase in the HSG cell line. Through this study, we found that the HSG cell line expressed molecules participating in the WNK-OSR1-NKCC pathway, such as Wnk1, Wnk4, OSR1, SPAK, and NKCC1. The HSG cell line showed an intracellular $Ca^{2+}$ concentration ($[Ca^{2+}]_i$) increase in response to hypotonic stimulation, and the response was synchronized with the phosphorylation of OSR1. Interestingly, when we inhibited the hypotonically induced $[Ca^{2+}]_i$ increase with nonspecific $Ca^{2+}$ channel blockers such as 2-aminoethoxydiphenyl borate, gadolinium, and lanthanum, the phosphorylated OSR1 level was also diminished. Moreover, a cyclopiazonic acid-induced passive $[Ca^{2+}]_i$ elevation was evoked by the phosphorylation of OSR1, and the amount of phosphorylated OSR1 decreased when the cells were treated with BAPTA, a $Ca^{2+}$ chelator. Finally, through that process, NKCC1 activity also decreased to maintain the cell volume in the HSG cell line. These results indicate that $Ca^{2+}$ may regulate the WNK-OSR1 pathway and NKCC1 activity in the HSG cell line. This is the first demonstration that indicates upstream $Ca^{2+}$ regulation of the WNK-OSR1 pathway in intact cells.

• Fisheries and Aquatic Sciences
• /
• v.24 no.11
• /
• pp.360-369
• /
• 2021

Paralytic shellfish toxins (PSTs) and tetrodotoxin (TTX) are neurotoxins that display pharmacological activity that is similar to that of specific sodium channel blockers; they are the principle toxins involved in shellfish and puffer fish poisoning. In Korea, puffer fish is a very popular seafood, and several cases of accidental poisoning by TTX have been reported. Therefore, it is necessary to determine whether puffer fish poisoning incidents are caused by PSTs or by TTX. In this study, we used mouse bioassay (MBA) and liquid chromatograph-tandem mass spectrometry (LC-MS/MS) to determine the presence of PSTs and TTX in puffer fish from an area near Mireuk-do, Tong-Yeong on the southern coast of Korea from January through March, 2014. The toxicity of PSTs and TTX extracts prepared from three organs of each specimen was analyzed by MBA. Most of the extracts killed mice with typical signs of TTX and PSTs. The LC-MS/MS analysis of seven specimens of Takifugu pardalis and Takifugu niphobles, each divided into muscles, intestines, and liver, were examined for TTX. In T. pardalis, the TTX levels were within the range of 1.3-1.6 ㎍/g in the muscles, 18.8-49.8 ㎍/g in the intestines, and 23.3-96.8 ㎍/g in the liver. In T. niphobles, the TTX levels were within the range of 2.0-4.5 ㎍/g in the muscles, 23.9-71.5 ㎍/g in the intestines, and 28.1-114.8 ㎍/g in the liver. Additionally, the toxicity profile of the detected PSTs revealed that dcGTX3 was the major component in T. pardalis and T. niphobles. When PSTs were calculated as saxitoxin equivalents the levels were all less than 0.5 ㎍/g, which is below the permitted maximum standard of 0.8 ㎍/g. These findings indicate that the toxicity of T. pardalis and T. niphobles from the southern coast of Korea is due mainly to TTX and that PSTs do not exert an effect.

• Clinical and Experimental Pediatrics
• /
• v.51 no.9
• /
• pp.992-997
• /
• 2008

Purpose : Hypertension (HTN) is no longer an exclusively adult disease; the prevalence of pediatric HTN is increasing. To understand the evaluation and treatment of childhood HTN in Korea, we investigated, via a questionnaire, how hypertensive children are currently assessed and managed by pediatric cardiologists (CA) and nephrologists (NE). Methods : We surveyed 82 pediatric CA and 77 NE, regarding how they manage hypertensive children in Korea. Results : A total 75 replies were received to our questionnaire request (response rate: 47.15%). Routine blood pressure (BP) checks were more frequently performed by NE (CA: 5.7%, NE: 25%, P=0.03), but most respondents (86%) did not check BP routinely. Mercury sphygmomanometers were the most commonly used devices and ambulatory blood pressure monitoring was not frequently used. The goal BP in treated patients was set at the 95th percentile by 61% of respondents. NE used a lower BP goal in hypertensive children with renal disease (CA: 24%, NE: 64%, P=0.004) or DM (CA: 12.5%, NE: 50%, P=0.003). Angiotensin converting enzyme (ACE) inhibitors were the most commonly used agents (mean: 59%); following ACE inhibitors, CA preferred diuretics for hypertensive children with renal disease or cardiovascular disease, and NE preferred calcium channel blockers, regardless of underlying disease. Self-monitoring was the most frequent method for BP monitoring at home. Conclusion : In Korea, BP measurement is not yet a routine examination in treating hypertension. There are some differences in management strategies vis-$\grave{a}$-vis hypertension, between pediatric cardiologists and nephrologists. For the appropriate management and prevention of secondary disease in long-term studies, standard guidelines and education are needed for pediatricians.