• The Journal of the Korean dental association
• /
• v.40 no.4 s.395
• /
• pp.258-265
• /
• 2002

• Biomolecules & Therapeutics
• /
• v.16 no.3
• /
• pp.219-225
• /
• 2008

Taurine is the most abundant amino acid in many tissues and is found to be enhancing the bone tissue formation or inhibits the bone loss. Although it is reported that taurine reduces the alveolar bone loss through inhibiting the bone resorption, its functions of taurine and expression of taurine transporter (TauT) in bone have not been identified yet. The purpose of this study is to clarify the uptake mechanism of taurine in osteoblast using mouse osteoblast cell lines. In this study, mouse stromal ST2 cells and mouse osteoblast-like MC3T3-E1 cells as osteoblast cell lines were used. The activity of taurine uptake was assessed by measuring the uptake of [$^3H$]taurine in the presence or absence of inhibitors. TauT mRNA was detected in ST2 and MC3T3-E1 cells. [$^3H$]Taurine uptake by these cells was dependent on the presence of extracellular calcium ion. The [$^3H$]taurine uptake in ST2 cells treated with 4 mM calcium was increased by 1.7-fold of the control which was a significant change. In contrast, in $Ca^{++}$-free condition and L-type calcium channel blockers (CCBs), taurine transport to osteocyte was significantly inhibited. In oxidative stress conditions, [$^3H$]taurine uptake was decreased by TNF-$\alpha$ and $H_2O_2$. Under the hyperosmotic conditions, taurine uptake was increased, but inhibited by CCBs in hyperosmotic condition. These results suggest that, in mouse osteoblast cell lines, taurine uptake by TauT was increased by the presence of extracellular calcium, whereas decreased by CCBs and oxidative stresses, such as TNF-$\alpha$ and $H_2O_2$.

• The Korean Journal of Pain
• /
• v.20 no.2
• /
• pp.92-99
• /
• 2007

Background: A correlation between a T-type voltage activated calcium channel (VACC) and pain mechanism has not yet been established. The purpose of this study is to find out the effect of ethosuximide and mibefradil, representative selective T-type VACC blockers on postoperative pain using an incisional pain model of rats. Methods: After performing a plantar incision, rats were stabilized on plastic mesh for 2 hours. Then, the rats were injected with ethosuximide or mibefradil, intraperitoneally and intrathecally. The level of withdrawal threshold to the von Frey filament near the incision site was determined and the dose response curves were obtained. Results: After an intraperitoneal ethosuximide or mibefradil injection, the dose-response curve showed a dose-dependent increase of the threshold in a withdrawal reaction. After an intrathecal injection of ethosuximide, the threshold of a withdrawal reaction to mechanical stimulation increased and the increase was dose-dependent. After an intrathecal injection of mibefradil, no change occurred in either the threshold of a withdrawal reaction to mechanical stimulation or a dose-response curve. Conclusions: The T-type VACC blockers in a rat model of postoperative pain showed the antihyperalgesic effect. This effect might be due to blockade of T-type VACC, which was distributed in the peripheral nociceptors or at the supraspinal level. Further studies of the effect of T-type VACC on a pain transmission mechanism at the spinal cord level would be needed.

• Korean Journal of Clinical Pharmacy
• /
• v.26 no.3
• /
• pp.213-219
• /
• 2016

Objective: Although guideline recommends beta blockers (BBs) as first line antianginal agent and calcium channel blockers (CCBs) as alternatives after percutaneous coronary intervention (PCI), the prescription patterns in real practice are not in accordance with the guideline. We aimed to investigate the prescribing patterns of primary antianginal drug and relating factors in patients who underwent PCI. Methods: Patients who have undergone PCI without myocardial infarction (MI) from November 2012 to June 2014 and followed up at least one year in a tertiary teaching hospital were included. Prescribing patterns of primary antianginal drug before, at the time of, and one year after PCI were described. Factors affecting drug selection, and their relationship with incidence of clinical outcomes defined as MI and repeated PCI, unscheduled admission or visit related with heart problem were analyzed with multivariate logistic regression. Results: A total of 506 patients were included and as primary antianginal drugs, BB, CCB, and both were prescribed in 32.2%, 24.5%, and 17.8% of patients, respectively. Also, neither BB nor CCB was prescribed at the time of PCI in 25.5% of patients. Compared with BB, CCBs were more likely prescribed in patients who had hypertension (Odds Ratio, OR 2.18, 95% confidence interval, CI 1.16-4.07), use of same class before PCI (OR 7.18, 3.37-15.2) and concomitant angiotensin receptor blocker (ARB) use (OR, 1.92, 95% CI 1.10-3.33). Incidence of clinical outcomes were not significantly greater in patients who prescribed CCB compared with BB at the time of PCI (aOR 1.32, CI 0.65-2.68). Conclusion: This study demonstrated that half of the patients who underwent PCI were prescribed BB. CCB were favored in patients with hypertension, use of same class before PCI, and concomitant ARB use. Significant difference in clinical outcome was not observed between BB and CCB selection as primary antianginal drug.

• Bulletin of the Korean Chemical Society
• /
• v.30 no.11
• /
• pp.2707-2712
• /
• 2009

5-$HT_{3}$ receptor;5-$HT_{3A}$ receptor channel activity;Novel 5-$HT_{3}$ receptor channel current blockers;Chlorophenyl substituted piperazinylethylaminomethylpyrazoles; The 5-$HT_{3A}$ receptors are one of ligand-gated ion channels and are known to be involved in visceral pain, anxiety, or anticancer agent-induced nausea and vomiting. In present study, we designed novel skeletons based on the developed 5-$HT_{3}$ receptor antagonists and evaluated their effects on 5-$HT_{3A}$ receptor channel currents ($I_{5-HT}$) of a series of pyrazole derivatives having N-chlorophenylpiperazine functionality (6-9). We found that most of N-p-chlorophenyl substituted piperazinyl-pyrazole derivatives (7b, 7c, 7e and 7h) exhibited the high potency for the inhibition of $I_{5-HT}$, whereas the compound without chloride (6) or with m-chlorophenyl group (a serious of 8 and 9) showed the low potency. These result indicate that p-chlorophenyl group is might play an important role for increasing the inhibitory potency on $I_{5-HT}$.

• Proceedings of the Korean Biophysical Society Conference
• /
• 1996.07a
• /
• pp.34-34
• /
• 1996

Previously we showed that $Ba^{2+}$ block of large conductance $Ca^{2+}$-activated $K^{+}$ (BK) channel was larger in the planar lipid bilayer formed with negatively-charged phosphatidylserine (PS) than neutral phosphatidylethanolamine (PE). In this work, have studied the blocking effect of two $K^{+}$ channel blockers with different mechanisms of action, $Ba^{2+}$ and tetraethylammonium (TEA), on BK channels of rat skeletal muscle. (omitted)itted)

• Proceedings of the Korean Biophysical Society Conference
• /
• 2002.06b
• /
• pp.19-19
• /
• 2002

The gating kinetics of an inward-rectifier K$\^$＋/ channel, ROMK2 (Kir1.lb), were described by a model having one open state and two closed states. The long closed state was abolished by EDTA, suggesting that it was due to block by divalent cations. These closures exhibit a biphasic voltage-dependence, implying that the divalent blockers can permeate the channel.(omitted)

• 한국생물공학회:학술대회논문집
• /
• 2005.10a
• /
• pp.422-423
• /
• 2005

• 한국생물공학회:학술대회논문집
• /
• 2005.10a
• /
• pp.192-193
• /
• 2005

• The Korean Journal of Pharmacology
• /
• v.32 no.2
• /
• pp.211-219
• /
• 1996

The inhibitory effect of cyclosporin A (CsA) on nitric oxide production is not related to the immunosuppressive action of the drug, but to the renal toxicity and arterial hyper-tension. In this study the experimental interventions to reverse the inhibition of nitric oxide production by cyclosporin A in rat aortic smooth muscle cells were examined. CsA inhibited the accumulation of nitrite, the stable end product of nitric oxide, in culture media in a concentration $(0.1{\sim}100{\mu}g/ml)-dependent$ manner. The inhibitory effect of CsA on nitrite accumulation were not antagonized by arginine (10 mM), a substrate of nitric oxide synthase, nor by calcium ionophore A23187 $(7{\mu}M)$. Forskolin, an activator of adenylate cyclase, which enhanced iNOS induction at transcriptional level, completely reversed the inhibitory action of CsA on nitrite accumulation. However, PMA (2 nM) and PDB (50 nM), PKC activators, increased the inhibitory action of CsA on nitrite accumulalion. From these results, it is suggested that cyclic AMP-elevating agents may be candidates of therapeutic agents in prevention and treatment of renal toxicity and arterial hypertension induced by CsA. Among conventional antihypertensive drugs, calcium channel blockers and ${\alpha}-blockers$ are preferred to ${\beta}-blockers$.