• Journal of Pharmaceutical Investigation
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• 제37권2호
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• pp.107-111
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• 2007

Epigallocatechin gallate (EGCC), a flavonoid, is the main component of green tea extracts. EGCG has been reported to be an inhibitor of P-glycoprotein (P-gp) and cytochrom P450 3A(CYP3A4). This study investigated the effect of long-term administration of EGCG on the pharmacokinetics of verapamil in rats. Pharmacokinetic parameters of verapamil were determined after oral administration of verapamil (9 mg/kg) in rats pretreated with EGCG (7.5 mg/hg) for 3 and 9 days. Compared to oral control group, the presence of EGCG significantly (p<0.01) increased the area under the plasma concentration-time curve (AUC) of verapamil by 102% (coad), 83.2% (3 days) and 52.3% (9 days), and the peak concentration $(C_{max})$ by 134% (coad), 120% (3 days) and 66.1% (9 days). The absolute bioavailability (A.B.%) of verapamil was significantly (p<0.01) higher by 8.4% (coad), 7.7% (3 days), 6.4% (9 days) compared to control (4.2%), and presence of EGCG was no significant change in the terminal half-life $(t_{1/2})$ and the time to reach the peak concentration $(T_{max})$ of verapamil. Our results indicate that EGCG significantly enhanced oral bioavailability of verapamil in rats, implying that presence of EGCG could be effective to inhibit the CYP3A4-mediated metabolism and P-gp efflux of verapamil in the intestine. Drug interactions should be considered in the clinical setting when verapamil is coadministrated with EGCG or EGCG-containing dietary.

• 대한의생명과학회지
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• 제2권2호
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• pp.153-158
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• 1996

Verapamil은 항암제에 대한 내성을 극복하기 위하여 실험적으로 사용하는 대표적인 약제로 알려져 있다 본 연구에서는 부인과 종양중 자궁경부암 치료시에 발생하는 항암 화학요법제에 대한 내성을 극복하기 위한 기초적인 실험으로 인체 자궁경부암 유래의 HeLa 및 Caski 세포주를 이용, MTT법으로 verapamil과 5-FU 및 DDP를 단독 혹은 병용 처리하여 세포독성 상승효과를 측정하였다. Verapamil 단독투여시 각 세포주는 용량에 비례하여 세포독성이 증가하였으며, 각 항암제와의 병용 투여시에 세포독성의 상승효과가 관찰이 되었으며, HeLa세포주에서 그 효과가 가장 높았다. 이러한 결과를 바탕으로 세포내 내성발현의 기전의 탐구가 필요하며 자궁경부암 화학요법에 verapamil사용의 이론적인 가능성을 제시하고 있다

• Archives of Pharmacal Research
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• 제28권4호
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• pp.483-487
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• 2005

The aim of this study was to investigate the pharmacokinetic changes of verapamil and its major metabolite, norverapamil, after oral administration of verapamil (10 mg/kg) in rabbits with slight, moderate and severe hepatic failure induced by carbon tetrachloride. The plasma verapamil concentrations in all groups of hepatic failure were significantly higher (p<0.01) than the control. However, the plasma norverapamil concentrations in severe hepatic failure were significantly higher (p<0.05) than the control. The peak concentrations ($C_{max}$) and the areas under the plasma concentration-time curve (AUC) of verapamil in the rabbits were significantly (p<0.01) higher than the control. The absolute bioavailability ($F_{A.B}$) and the relative bioavailability ($F_{R.B}$) of verapamil in the rabbits with hepatic failure were significantly higher ($13.6-22.2\% and 150-244\%$, respectively) than the control ($9.1\% and 100\%$, respectively). Although the AUC and $C_{max}$ of its major metabolite, norverapamil, in slight, moderate hepatic failure were not significantly lower than the control, the metabolite-parent AUC ratio in all groups of hepatic failure was decreased significantly (p<0.05, in slight group; p<0.01, in moderate and severe group) than the control. This could be due to decrease in metabolism of verapamil in the liver because of suppressed hepatic function in the hepatic failure groups because verapamil is mainly metabolized in the liver. From our data, it would seem appropriate that in patients with liver disease, doses of verapamil should be decreased by degree of hepatic failure.

• Tuberculosis and Respiratory Diseases
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• 제40권3호
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• pp.223-235
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• 1993

연구배경 : 대식세포 및 호중구에서 생산되는 superoxide는 외부에서 침입한 병원균을 죽이는 유익한 면이 있는 반면 자체 폐조직에 손상을 주어 폐손상을 일으키기도 한다. 임상에서 중요한 내독소에 의한 성인성호흡장애증후군등의 폐손상시 superoxide 등의 산소유리기가 중요역할을 하는 것으로 알려져 있으며 superoxide의 생산에는 칼슘이 중요한 조절기능을 담당한다. 내독소에 의한 급성폐손상의 경우 실험적으로 verapamil을 투여시 폐부종등의 증상이 완화되는 것이 알려져 있어 칼슘길항제인 verapamil의 산소유리기의 생산에 마치는 영향에 대한 연구가 많이 이루어지고 있다. 그러나 지금까지 폐포대식세포에서 superoxide의 생산에 대한 내독소와 verapamil의 영향을 같이 관찰한 실험은 없었다. 방법 : 본 실험에서는 백서의 폐포대식세포에서 protein kinase C를 직접 자극하는 phorbol myristate acetate 자극에 의한 superoxide의 생산을 측정하고 내독소 및 verapamil이 superoxide의 생산에 미치는 영향을 관찰하고 내독소와 verapamil을 동시에 투여하여 내독소에 의해 대식세포가 활성화되어 superoxide의 생산이 증가하는 priming 효과에 verapamil이 어떠한 영향을 미치는 가를 관찰하였다. 결과 : 폐포대식세포를 PMA로 자극시 기저상태에 비해 3.15배의 superoxide가 생산되었으며 이는 세포외 칼슘의 유무와 전혀 무관하였다. 그리고 내독소 (E. coli 055-B5)로 1시간 전처치후 PMA로 자극시 superoxide의 생산은 0.1 ug/ml 에서 최대로 43% 증가하였다. 또한 verapamil은 대식세포에서 PMA 자극에 의한 superoxide의 생산을 억제하였으며 세포외 칼슘이 없는 상태에서도 억제효과는 나타나 verapamil의 억제효과가 칼슘의 세포내 이동을 차단하는 기전에 의한 것이 아님을 관찰하였다. 내독소에 의한 대식세포에서의 superoxide의 생산의 증가는 verapamil이 없는 경우 30%의 증가에서 verapamil을 같이 투여한 경우 13%의 증가로 유의하게 감소하였다. 이는 내독소에 의한 대식세포의 priming에 칼슘이 영향을 미친다는 간접증거가 된다고 사료된다. 결론 : 이상의 결과로 verapamil은 PMA 자극에 의한 대식세포의 superoxide의 생산을 억제하며 폐포대식세포에 대한 내독소의 priming 효과도 억제하여 이는 내독소에 의한 폐손상시 verapamil의 효과의 한 기전이 되리라 사료된다.

• BMB Reports
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• 제29권4호
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• pp.314-320
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• 1996

The effects of non-cytotoxic concentrations of tamoxifen, verapamil, and trifluoperazine on doxorubicin cytotoxicity in five human breast cancer cell lines were studied. A non-cytotoxic concentration of tamoxifen resulted in enhanced doxorubicin cytotoxicity in HTB-123, HTB-26, and MCF-7. In these three cell lines, a combination of tamoxifen with verapamil resulted in even more increased doxorubicin cytotoxicity. Addition of verapamil or trifluoperazine alone did not influence the doxorubicin cytotoxicity significantly. Only in HTB-19 did coincubation with verapamil increase the doxorubicin cytotoxicity. In HTB-123, combination of tamoxifen with trifluoperazine increased the doxorubicin cytotoxicity significantly. In the cell lines where co-incubation with tamoxifen increased doxorubicin sensitivity, high estrogen receptor expression was detected. However, HTB-20, where tamoxifen did not enhance doxorubicin action, was also estrogen receptor positive. None of the cell lines had multidrug resistance related drug efflux and drug retention was not increased by the treatment with tamoxifen and verapamil. Cell cycle traverses were not altered by incubation with tamoxifen, verapamil or combinations thereof. These observatlons suggest mechanism of non-cytotoxic concentrations of tamoxifen and verapamil on doxorubicin cytotoxicity may involve one or more other cellular processes besides those of interference of estrogen binding to its receptor, cell cycle perturbation, or drug efflux blocking.

• 대한약리학회지
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• 제22권2호
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• pp.135-143
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• 1986

저자는 적출관류 토끼 신장기능에서 칼슘의 역할과 furosemide의 이뇨작용에 미치는 영향을 관찰하여 다음과 같은 결과를 얻었다. hydralazine놔 verapamil을 주로 신혈관 저항의 감소로 이뇨작용을 나타냈다. furosemide를 hydralazine 또는 verapamil 병합투여시 뚜렷한 이뇨작용이 나타났으며 두군 사이에 차이는 없었다. quinidine은 신혈관 수축을 일으켰으나 이뇨작용이 나타났으며 furosemide의 이뇨작용을 항진시켰다. 칼슘제외된 관류액으로 관류시 칼슘은 신혈관 수축에도 불구하고 이뇨작용이 나타났으며 furosemide의 이뇨작용을 항진시켰다. quinidine은 칼슘이 제외된 상태에서 신장기능 및 furosemide의 이뇨작용에 영향을 미 치지 못하였으나 calcium 병합투여시 과도한 신혈관 수축으로 항 이뇨작용을 보였다. verapamil은 칼슘이 제외된 상태에서 약간의 이뇨작용을 보였지만 칼슘 및 furosemide의 이뇨작용을 변화시키지 못하였다. 이상의 성적은 적출관류 토끼 신장에서 칼슘, verapamil 및quinidine이 이뇨작용이 있으며 칼슘은 furosemide의 이뇨작용을 항진시킨다.

• Journal of Pharmaceutical Investigation
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• 제24권4호
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• pp.289-295
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• 1994

Pharmacokinetic drug interaction between phenytoin and verapamil was investigated following i.v. administration of two drugs concomitantly to rabbits. Verapamil was coadministered with phenytoin (5 mg/kg) to rabbits at the doses of 0.5,1 and 2 mg/kg, respectively. Plasma concentration and AUC of phenytoin were increased significantly, but volume of distribution and total body clearance were decreased significantly (p<0.05) at doses of 1mg and 2mg/kg of verapamil, respectively. From the results of this experiment, it is desirable that dosage regimen of phenytoin should be adjusted and that therapeutic drug monitoring should be performed for reduction of side or toxic effect when phenytoin should be administered with verapamil in clinical practice.

• Bulletin of the Korean Chemical Society
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• 제32권7호
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• pp.2274-2278
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• 2011

Verapamil is a calcium channel blocker and is classified as a class IV anti-arrhythmic agent. It is used in the control of supra ventricular tachyarrhythmias, and in the management of classical and variant angina pectoris. It is also used in the treatment of hypertension and used as an important therapeutic agent for angina pectoris, ischemic heart disease, hypertension and hypertrophic cardiomyopathy. Verapamil commonly co-administered with NSAIDs (non-steroidal anti-inflammatory drugs) i.e. diclofenac sodium, flurbiprofen, Ibuprofen, mefanamic acid and meloxicam. A simple and rapid RP-HPLC method for simultaneous determination and quantification of verapamil and NSAIDs was developed and validated. The mobile phase constituted of acetonitrile: water (55:45) whose pH was adjusted at 2.7 and pumped at a flow rate of 2.0 mL $min^{-1}$ at 230 nm. The proposed method is simple, precise, accurate, low cost and least time consuming for the simultaneous determination of verapamil and NSAIDs which can be effectively applied for the analysis of human serum.

• Archives of Plastic Surgery
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• 제32권5호
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• pp.625-635
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• 2005

In this study, the effects of verapamil on growth rate, apoptosis, production of transforming growth factor (TGF-${\beta}$) and fibronectin were evaluated in keloid and normal human dermal fibroblasts. Both fibroblasts were primarily cultured from earlobe keloids of three female patients and treated with various concentrations of verapamil. Cell toxicity was assessed by MTT assay, growth rate and apoptosis by FACS, and the production of TGF-${\beta}$ and fibronectin by ELISA and Western blot, respectively. In the $MTT_{50}$, the cell growth was more suppressed in keloid fibroblasts. In the $MTT_{90}$, cell growth was more stimulated in normal fibroblasts. No significant effect appeared on TGF-${\beta}$ expression but an increase in extracellular fibronectin secretion was found in keloid fibroblasts. Keloid fibroblasts responded to verapamil more sensitively, and the percentage of apoptosis was higher at the $MTT_{50}$l. In brief, verapamil had growth-inhibitory effect with inducing apoptosis at the $MTT_{50}$, but rather growth-stimulatory effect at the $MTT_{90}$. The biphasic effect of verapamil depending on the dose might explain one of the reasons of relapse after keloid treatment with verapamil. Clinical application with high concentration (2.5 mg/ml) is advised unless excessive dosage is used.

• The Korean Journal of Pain
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• 제32권4호
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• pp.256-263
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• 2019

Background: Antinociceptive anti-inflammatory drugs have many adverse effects. The goal of this investigation is to study the probable anti-inflammatory and analgesic effects of verapamil and N-acetylcysteine (NAC) in experimental rats. Methods: Adult male Wistar rats were randomly divided into 4 groups in the antinociceptive study, each containing 6 rats; the normal control group, which received saline (1 mL/kg); the diclofenac group, which received diclofenac sodium (5 mg/kg); the NAC group, which received NAC (125 mg/kg); and the verapamil group, which received verapamil (8 mg/kg). In the anti-inflammatory study, 5 groups were used, the 4 previous groups with the addition of an edema control group, received saline and were subjected to formalin test. Hot plate latency time was recorded for antinociceptive evaluation. Paw edema thickness and biochemical parameters were recorded for anti-inflammatory evaluation. Results: Administration of NAC showed significant prolongation of hot plate latency time at 1 hour when compared to the control group while verapamil showed a significant prolongation of hot plate latency time at 1 and 2 hours when compared to the control group and NAC group values. Administration of NAC and verapamil significantly decreased paw edema thickness at 2, 4, and 8 hours when compared to edema control values. Regarding biochemical markers, NAC and verapamil significantly decreased serum nitric oxide synthase, C-reactive protein, and cyclooxygenase-2 levels compared to the edema control value. In accordance, a marked improvement of histopathological findings was observed with both drugs. Conclusions: NAC and verapamil have antinociceptive and anti-inflammatory effects comparable to diclofenac sodium.