• Asian Pacific Journal of Cancer Prevention
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• v.17 no.8
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• pp.3917-3921
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• 2016

Background: The association between calcium channel blockers (CCBs) and survival in cancer patients remains unclear and the results of related studies are conflicting. The objective of the study was to investigate the association between calcium channel blockers (CCBs) use and survival in cancer patients. Materials and Methods: We searched PubMed, EMBASE, Web of Science and Cochrane Library for studies published before January 2016 with the terms related to CCBs and survival in cancer patients. The information was reviewed and extracted by two evaluators independently. Data of publications was extracted and calculated into hazard ratios (HRs) for overall survival (OS). Statistical analysis was performed by using Review Manager 5.3. Results: There were 11 studies included in our meta-analysis. Analysis of all studies showed that CCBs use was not associated with survival in cancer patients (HR=1.07; 95% CI: 0.91-1.25; P=0.42). No association between CCBs use and overall survival in cancer patients was existed whether in Asian (HR=1.18, 95% CI: 0.72-1.93; P=0.52) or Caucasian population (HR=1.03, 95% CI: 0.89-1.20; P=0.66). Conclusions: There is no evidence that CCBs use is associated with a better or worse outcome of survival in cancer patients.

• Journal of Embryo Transfer
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• v.32 no.3
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• pp.243-248
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• 2017

Antioxidants have been added to cryoprotectant or in vitro culture medium for sperm to reduce the detrimental damage, such as reactive oxygen species. However, curcumin, an antioxidant, shows dual effect on the viability and progressive motility of bovine sperm exposed to hydrogen peroxide. Low concentration of curcumin increases sperm viability and progressive motility, whereas high concentration of curcumin reduces them. This study was performed to identify whether TREK-1 channel is related to low sperm viability and motility induced by high concentration of curcumin. Curcumin reduced TREK-1 channel activity in a dose-dependent manner. TREK-1 channel was expressed in sperm obtained from Korean native bull. Treatment with TREK-1 channel blockers, such as curcumin, fluoxetine, $GdCl_3$, and spadin, significantly reduced sperm viability and motility (p < 0.05). However, TREK-1 channel activators showed different effect; linoleic acid showed an increase in sperm viability and motility, and wogonin did not affect them. These results show that TREK-1 channel is involved in the regulation of sperm viability and motility. In particular, high concentration of curcumin might reduce sperm viability and progressive motility of Korean native bull through blockage of TREK-1 channel.

• YAKHAK HOEJI
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• v.58 no.2
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• pp.141-149
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• 2014

Background: Oriental lifestyle for treating diseases has been developed and well-accepted for a long time among Koreans. Sasang Constitution theory, originated from Korean traditional medicine, suggests that medication treatment should be differentiated by each patient's body classification (So-yang [SY], So-eum [SE], Tae-yang [TY], and Tae-eum [TE]), in contrary to western medicine's theory that medication should be applied equally by disease indication without such classification. However, the pharmacotherapeutic outcomes of these theories have not been compared to date. In this study, we aimed to compare the two theories by evaluating blood pressure (BP), which is lowered as a therapeutic outcome, among hypertensive patients taking angiotensin II receptor blockers (ARBs) or calcium channel blockers (CCBs), two most commonly used antihypertensive classes in Korea. Methods: From April 2006 to June 2012, we retrospectively collected data on hypertensive patients with Sasang Constitution classification at Kyunghee University Hospital at Gangdong, one of the East-West collaborative medical centers in Korea. We collected information on age, gender, underlying diseases, antihypertensive drugs (ARB, CCB, ARB+CCB), and BP by reviewing the electronic medical records. We excluded patients with missing blood pressure at baseline or follow-up, or those who had a change in their antihypertensive drug class during follow-up. Results: We selected a total of 573 patients (SY: 165, SE: 158, TY: 0, TE: 250). Baseline BPs were on average 139.0/82.0 mmHg for SY, 137.8/78.5 mmHg for SE, and 138.7/79.2 mmHg for TE. In all three groups, CCBs were the most prescribed, followed by combination therapy with ARB+CCB, then ARBs. BP reduction after 1 month of initial medication was significantly different among the drug classes, but not in Sasang constitutional classification (ARB [SY: -12.4/-4.7, SE: -12.3/-2.5, TE: -8.6/-1.8], CCB [SY: -12.3/-5.4, SE: -13.0/-2.3, TE: -10.8/-6.0], ARB+CCB [SY: -15.6/-6.7, SE: -18.4/-8.1, TE: -20.2/-6.7], drug [$P{\leq}0.05$/P>0.05], constitutional type [P>0.05/P>0.05]). Conclusion: We observed significant differences in reduction of blood pressure by classes of drugs (ARB+CCB>CCB>ARB) but not by Sasang constitutional classification. Therefore, current approach of antihypertensive pharmacotherapy assisted by Western medicine is appropriate for treatment of hypertension. However, further larger scale or prospective studies are required in order to confirm these results.

• Bulletin of the Korean Chemical Society
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• v.32 no.1
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• pp.251-262
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• 2011

Human ether-a-go-go related gene (hERG) potassium channel blockade, an undesirable side effect which might cause sudden cardiac death, is one of the major concerns facing the pharmaceutical industry. The purpose of this study is to develop an in silico QSAR model which uncovers the structural parameters of T-type calcium channel blockers to reduce hERG blockade. Comparative molecular similarity indices analysis (CoMSIA) was conducted on a series of piperazine and benzimidazole derivatives bearing methyl 5-(ethyl(methyl)amino)-2-isopropyl-2-phenylpentanoate moieties, which was synthesized by our group. Three different alignment methods were applied to obtain a reliable model: ligand based alignment, pharmacophore based alignment, and receptor guided alignment. The CoMSIA model with receptor guided alignment yielded the best results : $r^2$ = 0.955, $q^2$ = 0.781, $r^2_{pred}$ = 0.758. The generated CoMSIA contour maps using electrostatic, hydrophobic, H-bond donor, and acceptor fields explain well the structural requirements for hERG nonblockers and also correlate with the lipophilic potential map of the hERG channel pore.

• Journal of Microbiology and Biotechnology
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• v.14 no.3
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• pp.456-465
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• 2004

$K^+$ efflux through a certain type of $K^+$ channels causes the change of membrane potential and leads to cAMP synthesis in the transmembrane cell signaling for the initiation of sperm motility in the salmonid fishes. The addition of $Ca^{2+}$ conferred motility to the trout sperm that were immobilized by external $K^+$ and other alkaline metals, $Rb^+$ and $Cs^{2+}$, suggesting the participation of external $Ca^{2+}$ in the initiation of sperm motility. L-type $Ca^{2+}$ channel blockers such as nifedipine, nimodipine, and FS-2 inhibited the motility, but N-type $Ca^{2+}$ channel blocker, w-conotoxin MvIIA, did not. On the other hand, the membrane hyperpolarization and cAMP synthesis were suppressed by $Ca^{2+}$ channel blockers, nifedipine, and trifluoroperazine. Furthermore, these suppressions were relieved by the addition of $K^+$ ionophore, valinomycin. Inhibitors of calmodulin, such as W-7, trifluoperazine, and calrnidazol-C1, inhibited the sperm motility, membrane hyperpolarization, and cAMP synthesis. The results suggest that $Ca^{2+}$ influx through $Ca^{2+}$ channels that are sensitive to specific $Ca^{2+}$ channel blockers and calmodulin participate in the changes of membrane potential, leading to synthesis of cAMP in the cell signaling for the initiation of trout sperm motility.

• Korean Journal of Veterinary Research
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• v.44 no.4
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• pp.515-522
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• 2004

The vasorelaxant effect of serotonin reuptake inhibitor fluoxetine was investigated in rat isolated thoracic aorta. Fluoxetine induced a concentration-dependent relaxation in aorta precontracted with phenylephrine (PE) and KCl. These relaxations were suppressed by removal of the endothelium (-E) or pretreatment of nitric oxide synthase inhibitors, N(G)-nitro-L-arginine (L-NNA) and N(omega)-nitro-Larginine methyl ester (L-NAME), guanylate cyclase inhibitors, methylene blue (MB) and 1H-[1,2,4]oxadiazolo [4,3-a]quinoxalin-1-one (ODQ), and $Ca^{2+}$ channel blockers, nifedipine and verapamil, in PE-precontracted +E rings. However, fluoxetine-induced relaxations were not suppressed by pretreatment of $K^{+}$ channel blockers, tetrabutylammonium and glibenclamide, in PE-precontracted endothelium intact (+E) rings. The fluoxetine-induced relaxations were not suppressed by removal of the endothelium or pretreatment of LNNA and MB in KCl-precontracted +E rings. Also, fluoxetine inhibited PE-induced sustained contraction in +E rings. These inhibitory effects of fluoxetine on contractions could be reversed by removal of the endothelium or pretreatment of L-NNA, L-NAME, MB, ODQ, nifedipine and verapamil, but not by pretreatment of etrabutylammonium and glibenclamide. These findings suggest that the vasorelaxant effect of fluoxetine is modulated by intracellular $Ca^{2+}$ with an involvement of endothelial NO-cGMP pathway and also may be related to the inhibition of $Ca^{2+}$ entry through voltage-gated channel.

• YAKHAK HOEJI
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• v.47 no.6
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• pp.382-389
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• 2003

This study has collected prescriptions of individual chronic outpatients in an army hospital, analysed them, and investigated the possible drug interactions. It also reviewed the mechanism of drug interactions. Out of total of 42 outpatients with chronic diseases, the percentages of populations having hypertension, hypertension with diabetes, uncomplicated diabetes, hyperlipidemia, hypertension with cardiac insufficiency, and ventricular septal defect were 62%, 19%, 10%, 5%, 2%, and 2%, in the corresponding order. The average number medications prescribed for the outpatients were 2.5 with the highest frequency of five medications in two patients. The number of drug-drug interactions detected was 456 prescriptions out of total of 1104 prescriptions during the study period, accounting for 41.3%. The most frequent drug-drug interaction was between beta-blockers and calcium channel blockers with 132 prescriptions followed by one between beta-blockers and cimetidine with 89 prescriptions. Based on the high incidence of possibly dangerous drug interactions, much attention needs to be aid to the drug-drug interactions in the pharmacotherapy for the treatment of outpatients with chronic diseases in army hospital setting.

• International Journal of Oral Biology
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• v.36 no.2
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• pp.43-50
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• 2011

Voltage dependent calcium channel (VDCC), one of the most important regulator of $Ca^{2+}$ concentration in neuron, play an essential role in the central processing of nociceptive information. The present study investigated the antinociceptive effects of L, T or N type VDCC blockers on the formalin-induced orofacial inflammatory pain. Experiments were carried out on adult male Sprague-Dawley rats weighing 220-280 g. Anesthetized rats were individually fixed on a stereotaxic frame and a polyethylene (PE) tube was implanted for intracisternal injection. After 72 hours, 5% formalin ($50 \;{\mu}L$) was applied subcutaneously to the vibrissa pad and nociceptive scratching behavior was recorded for nine successive 5 min intervals. VDCC blockers were administered intracisternally 20 minutes prior to subcutaneous injection of formalin into the orofacial area. The intracisternal administration of 350 or $700{\mu}g$ of verapamil, a blocker of L type VDCC, significantly decreased the number of scratches and duration in the behavioral responses produced by formalin injection. Intracisternal administration of 75 or $150 \;{\mu}g$ of mibefradil, a T type VDCC blocker, or 11 or $22\; {\mu}g$ of cilnidipine, a N type VDCC blocker, also produced significant suppression of the number of scratches and duration of scratching in the first and second phase. Neither intracisternal administration of all VDCC blockers nor vehicle did not affect in motor dysfunction. The present results suggest that central VDCCs play an important role in orofacial nociceptive transmission and a targeted inhibition of the VDCCs is a potentially important treatment approach for inflammatory pain originating in the orofacial area.

• YAKHAK HOEJI
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• v.41 no.4
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• pp.399-406
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• 1997

The effects of different $K^+$ channel blockers were investigated on the non-adrenergic non-cholinergic (NANC) relaxations in the circular muscle of the rabbit proximal stomach. Non-selective blockers of $K^+$ channels, 4-aminopyridine (4-AP, 3~30${\mu}M$) and tetraethylammonium (TEA, 100~1000${\mu}M$) significantly enhanced the NANC relaxations in a concentration-dependent manner. The enhancement was more prominent for the NANC relaxations induced by the electric field stimulation (EFS) with lower frequencies. Blockers of large conductance $Ca^{2+}$-activated $K^+$ channels, charybdotoxin and iberiotoxin, a blocker of small conduntance $Ca^{2+}$-activated $K^+$ channels, apamin and a blocker of ATP-sensitive $K^+$ channels, glibenclamide had no effect on the NANC relaxations, respectively. Exogeneous administration of nitric oxide (NO, 1~30${\mu}M$) caused concentration-dependent relaxations which showed a similarity to those obtained with EFS. None of the $K^+$ channel blockers had an effect on the concentration-dependent relaxation in response to NO. These results suggest that prejunctional $K^+$ channels regulate the release of NO from the NANC nerve in the rabbit proximal stomach as the inhibition of prejunctional $K^+$ channels increases the NANC relaxation induced by the EFS.

• Korean Journal of Clinical Pharmacy
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• v.32 no.2
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• pp.125-132
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• 2022

Background: Fixed-dose combinations have the advantage of improving patient compliance, but may increase the risk of duplicate prescriptions. As the use of fixed-dose combination antihypertensives increases, it is necessary to investigate the current status of class duplication prescriptions (CDP) in patients taking fixed-dose combination antihypertensives in Korea and to identify factors associated with CDP. Methods: We conducted a retrospective observational study using nationally representative claim data. Hypertensive patients aged 20 years or older taking fixed-dose combination antihypertensives were extracted. Among these patients, patients with CDP were identified. A chi-square test was applied to determine the differences between patients with CDP and non-CDP. The associated factors of CDP were identified through multiple logistic regression. Results: Of the 74,165 patients who were prescribed fixed-dose combination antihypertensives, 426 patients (0.6%) with CDP were identified. The most common antihypertensive class associated with CDP was calcium channel blockers (194 patients, 45.5%), followed by angiotensin II receptor blockers (136 patients, 31.9%). Patients aged 75 years or older (odds ratio [OR] 1.83, 95% confidence interval [CI] 1.02-3.52), chronic kidney disease (OR 4.45, 95% CI 2.15-8.25), chronic heart failure (OR 2.71, 95% CI 1.93-3.72), coronary artery disease (OR 2.22, 95% CI 1.60-3.03) and Medical Aid/Patriots and Veterans Insurance (OR 1.49, 95% CI 1.04-2.07) were significantly associated with increased CDP. Conclusions: The factors associated with CDP were the elderly, comorbidities, and low socioeconomic status. Since CDP can result in negative clinical outcomes, active intervention by the pharmacist is warranted.