To investigate effects of verapamil on primary cultured human urethral scar fibroblasts (USFs) and to provide basis for protecting the formation of urethra scar.
 Methods: The cell proliferation was evaluated with the cell counting kit (CCK)-8 method after USFs were incubated various verapamil concentrations (50, 100, 150, 200, or 250 μmol/L) or solvent for 12, 24, or 48 h. The protein level of matrix metalloproteinase (MMP) was evaluated with ELISA after cells were incubated with verapamil (100 μmol/L) or solvent (control cells) for 24 h.
 Results: The proliferation of USFs was obviously suppressed after verapamil treatment, which was in a dose-dependent and time-dependent manner. Meanwhile, the protein levels of MMP-2 and MMP-9 in the verapamil treatment group increased obviously compared with those of the control groups (P<0.05).
 Conclusion: Calcium channel blockers may prevent the excessive formation of urethra scar by inhibiting the proliferation of urethral scar fibroblasts and enhancing the activity of MMP.
Calcium Channel Blockers ; pharmacology ; Cell Proliferation ; drug effects ; Cells, Cultured ; Cicatrix ; prevention & control ; Fibroblasts ; drug effects ; Humans ; Matrix Metalloproteinase 2 ; drug effects ; Matrix Metalloproteinase 9 ; drug effects ; Matrix Metalloproteinase Inhibitors ; pharmacology ; Up-Regulation ; drug effects ; Urethra ; cytology ; pathology ; Verapamil ; pharmacology

OBJECTIVETo evaluate the effect of Radix euphorbiae pekinensis extract on the permeability and bioavailability of paclitaxel co-administered orally.

METHODSBased on Ussing Chamber and in vivo experiment, the permeability and bioavailability of paclitaxel were evaluated after oral co-administration with radix euphorbiae pekinensis in rats. The contents of paclitaxel in the permeates and the blood samples were determined using HPLC and LC-MS/MS method, respectively.

RESULTSIn Radix euphorbiae pekinensis co-administration group, the Papp of the mucosal-to-serosal (M-S) transport or serosal-to-mucosal transport (S-M) of paclitaxel in the jejunum or ileum segment differed significantly from those in verapamil co-administration group and blank control group (P<0.05), but the Papp of S-M transport in the colon showed no significant difference from that in the blank control group. In the blank group, the average absolute bioavailability (AB%) of orally administered paclitaxel was only 2.81%, compared to that of 7.63% in radix euphorbiae pekinensis group. The average AB% in verapamil group was about 1.5 times that of the blank group.

CONCLUSIONCo-administration of Radix euphorbiae pekinensis extract can increase the bioavailability of orally administered paclitaxel.

Administration, Oral ; Animals ; Biological Availability ; Biological Transport ; Chromatography, High Pressure Liquid ; Euphorbiaceae ; chemistry ; Paclitaxel ; pharmacokinetics ; Permeability ; Plant Extracts ; pharmacology ; Plant Roots ; chemistry ; Rats ; Tandem Mass Spectrometry ; Verapamil

The tumor multidrug resistance reversal effect of NPB304, a novel taxane, was studied. MTT assay was used to determine the IC50 of chemotherapy drugs. Western blotting assay was applied to analyze the expression of P-glycoprotein (P-gp). The effect of compounds on the P-gp function and P-gp ATPase activity was determined by rhodamine 123 (Rh123) accumulation assay and analysis kit, respectively. Molecular docking was employed to predict the binding force between compounds and P-gp. Transmembrane transport of NPB304 was analyzed using MDCK II and MDR1-MDCK II cell model. NPB304 displayed multidrug resistance reversal effect on KBV cells and MCF-7/paclitaxel cells, NPB304 collaborative with P-glycoprotein (P-gp) inhibitors verapamil enhanced the reversal activity, specifically, 10 μmol x L(-1) verapamil in combination with paclitaxel reversed resistance by 56.5-fold, while combined with NPB304 increased the reversal fold; NPB304 synergistically increased Rh123 accumulation in the resistant cells when combined with verapamil, and NPB304 at 0-1 μmol x L(-1) enhanced the ATPase activity activated by verapamil was observed. NPB304 existed the hydrophobic interactions with the TM regions of P-gp, and the binding force between NPB304 and the A chain of the TM region was stronger. P-gp ATPase activity assay demonstrated NPB304 at lower concentrations (0-1.5 μmol x L(-1)) could activate the P-gp ATPase, playing a role on inhibition of P-gp function. However, NPB304 did not have an obvious feature of P-gp substrate. NPB304 exerted itself and synergy with verapamil activity on reversing tumor resistance via inhibiting the P-gp function.
ATP-Binding Cassette, Sub-Family B, Member 1 ; metabolism ; Antineoplastic Agents ; pharmacology ; Biological Transport ; Drug Resistance, Multiple ; Drug Resistance, Neoplasm ; Drug Synergism ; Humans ; MCF-7 Cells ; Rhodamine 123 ; Taxoids ; pharmacology ; Verapamil ; pharmacology

OBJECTIVE: To investigate the protective effect of combined administration of verapamil and nitroglycerin on the function of canine transplanted lungs. METHODS: Twenty orthotopic left lung transplantations were performed in 40 canines, which were randomly divided into 4 groups. In group I (control), the donor lungs were perfused and preserved with LPD solution, while group II with LPD solution plus verapamil 0.1 g/L, group III with LPD solution plus nitroglycerin 0.1g/L, and group IV with LPD solution plus verapamil 0.1 g/L and nitroglycerin 0.1 g/L. Hemodynamics and graft gas exchange were assessed 0, 2 and 4 h after the operation. The lung grafts were harvested to measure the wet/dry weight ratio, malondialdehyde (MDA) contents and superoxide dismutase (SOD) activity. RESULTS: Compared with group I, II and III, the mean pulmonary artery pressure (MPAP), pulmonary vascular resistance index (PVRI), partial pressure of oxygen in arterial blood (PaO₂), dynamic compliance (Cdyn) and alveolar-arterial oxygen tension volume [P(A- a)O₂] in group IV were improved significantly (P<0.05). No significant difference in the partial pressure of carbondioxide (PaCO₂) and peak inspiratory pressure (PIP) was observed in the 4 groups (P>0.05). In group IV, the wet/dry weight ratio and MDA contents were lower than those in the other 3 groups, and the SOD activity was significantly higher than that of the other 3 groups (P<0.05). CONCLUSION Verapamil and nitroglycerin in LPD solution can protect the respiratory function of canine lung grafts by attenuating pulmonary edema and oxidative stress.
Animals ; Blood Gas Analysis ; Dogs ; Hemodynamics ; Lung ; Lung Transplantation ; Nitroglycerin ; pharmacology ; Organ Preservation ; Protective Agents ; Reperfusion Injury ; Verapamil ; pharmacology

To investigate the rat intestinal absorption of stearic acid-octaarginine (SA-R8) modified solid lipid nanoparticles containing paclitaxel (SA-R8-PTX-SLN), compared with the commercially available preparation of PTX (Taxol) and PTX-loaded solid lipid nanoparticles (PTX-SLN), the in situ intestinal absorption of SA-R8-PTX-SLN was investigated by means of single-pass rat intestinal perfusion technique. The absorptions of the preparations were investigated at different intestinal segments, different drug concentrations and in the presence of P-glycoprotein inhibitor (verapamil). The results showed that PTX could be absorbed at each intestinal segment and the three preparations all showed maximum absorptions at the duodenum. The cumulative absorptions of three preparations at each intestinal segment appeared SA-R8-PTX-SLN > PTX-SLN > Taxol (P < 0.05). SA-R8-PTX-SLN showed a liner absorption manner at the duodenum in the examined drug concentration range. The cumulative absorptions of Taxol and PTX-SLN were significantly promoted after the addition of P-glycoprotein inhibitor (verapamil) into the preparation (P < 0.05), but absorption of SA-R8-PTX-SLN existed no significantly difference compared with the preparation without verapamil (P > 0.05). SA-R8 and SLN might both effectively improve the oral absorption of PTX in the intestinal tract.
ATP-Binding Cassette, Sub-Family B, Member 1 ; antagonists & inhibitors ; Animals ; Antineoplastic Agents, Phytogenic ; administration & dosage ; chemistry ; pharmacokinetics ; Cell-Penetrating Peptides ; chemistry ; Drug Carriers ; Intestinal Absorption ; drug effects ; Lipids ; chemistry ; Male ; Nanoparticles ; Oligopeptides ; chemistry ; Paclitaxel ; administration & dosage ; chemistry ; pharmacokinetics ; Perfusion ; Rats ; Rats, Sprague-Dawley ; Stearic Acids ; chemistry ; Verapamil ; pharmacology

We studied medium alkalinization in Salvia miltiorrhiza suspension cultures treated with salicylic acid and the effect of Ca2+ in this process through application of calcium channel antagonists (Verapamil, LaCl3, LiCl, 2-APB) and ionophore A23187. The results show that salicylic acid could induce significant medium alkalinization in S. miltiorrhiza culture. Verapamil and LaCl3 or LiCl and 2-APB, two different groups of calcium channel antagonist, significantly inhibited the medium alkalinization induced by salicylic acid. However, the suppression effect of verapamil or LaCl3 on medium alkalinization induced by salicylic acid was higher than that of LiCl or 2-APB. When two types of calcium channel inhibitor (LaCl3 and 2-APB) were used together, the medium alkalinization induced by salicylic acid was completely suppressed and even reduced the pH in medium. On the other hand, A23187 could promote the medium alkalinization. Based on the results above, we speculated that salicylic acid could induce significant medium alkalinization in S. miltiorrhiza culture, depending on the calcium from both extracell and intracell. Moreover, calcium from extracell plays a more dominant role in this process. Reveal of relationship in this research between Ca2+ and medium alkalinization can provide theory evidence for mechanism of the plant secondary metabolism.
Calcimycin ; pharmacology ; Calcium ; chemistry ; Calcium Channel Blockers ; pharmacology ; Calcium Ionophores ; pharmacology ; Cell Culture Techniques ; Culture Media ; chemistry ; Salicylic Acid ; pharmacology ; Salvia miltiorrhiza ; metabolism ; Verapamil ; pharmacology

OBJECTIVETo study the transport mechanism of baicalin of Scutellariae Radix extracts and the effect of Angelica dahurica extracts on the intestinal absorption of baicalin by using Caco-2 cell monolayer model, in order to analyze the effect mechanism of Angelica dahurica extracts on the intestinal absorption of baicalin.

METHODThe Caco-2 cell monolayer model was established with human colonic adenocarcinoma cells, and used to study the effect of pH, time, drug concentration and temperature on the transport of baicalin in Scutellariae Radix extracts, the effect of P-gp and MRP protein-dedicated inhibitors on the bidirectional transport of baicalin in Caco-2 cell model, and the effect of angelica root extracts on baicalin absorption and transport.

RESULTBaicalin was absorbed well at 37 degrees C and under pH 7.4 condition and concentration dependent. Its proteins became inactive at 4 degrees C, with a low transport. The bi-drectional transfer PDR was 0. 54. After P-gp inhibitor verapamil and MRP inhibitor probenecid were added, the value of PappBL-AP of baicalin decreased, but without any difference in PDR. The transport of baicalin was improved by 2.34, 3.31 and 3.13 times, after A. dahurica extract coumarin, volatile oil, and mixture of coumarin and volatile oil.

CONCLUSIONThe transport mechanism of baicalin is mainly passive transfer and supplemented with efflux proteins involved. A. dahurica extracts can enhance the absorption of baicalin, which may be related to the passive transfer merchanism of baicalin. A. dahurica extracts' effect in opening the close junction among cells may be related to its expression or function in inhibiting efflux proteins.

ATP-Binding Cassette, Sub-Family B, Member 1 ; antagonists & inhibitors ; metabolism ; Angelica ; chemistry ; Biological Transport ; drug effects ; Caco-2 Cells ; Cell Line, Tumor ; Coumarins ; chemistry ; pharmacology ; Drug Interactions ; Drugs, Chinese Herbal ; chemistry ; pharmacology ; Flavonoids ; pharmacokinetics ; Humans ; Intestinal Absorption ; drug effects ; physiology ; Oils, Volatile ; chemistry ; pharmacology ; Plant Extracts ; chemistry ; pharmacology ; Plant Roots ; chemistry ; Probenecid ; pharmacology ; Scutellaria baicalensis ; chemistry ; Verapamil ; pharmacology

OBJECTIVETo study in situ intestinal absorption kinetics of baicalin contained in Tiangou Jiangya capsules, and the effect of different intestinal segments, pH value, drug concentration and P-gp inhibitor on the absorption.

METHODThe in situ intestinal perfusion test was adopted, and HPLC method was used to determine the content of baicalin in samples at different time points. Ultra-violet (UV) spectrophotometry was used to determine the content of phenol red in samples at different time points.

RESULTWhen pH value was at 5. 0, 6. 5, 7. 4, the absorption of baicalin was not impacted. P-gp inhibitor verapamil could enhance the absorption of baicalin. When the quality concentration of the test solution ranged between 5-20 g L -1 , the linearity of the absorption amount of baicalin increased. The absorption kinetic equation of baicalin was Y = -0. 073 7X +0. 118 7 (r = 0. 994 8) , K. 0. 073 7 h -1 , t1/2 9. 40 h.

CONCLUSIONBaicalin is mainly absorbed in colon. The absorption of baicalin shows the first-order kinetics process, with the absorption mechanism of passive diffusion. Baicalin is a substrate for P-gp.

ATP-Binding Cassette, Sub-Family B, Member 1 ; antagonists & inhibitors ; Animals ; Benzyl Alcohols ; chemistry ; standards ; Female ; Flavonoids ; chemistry ; metabolism ; standards ; Furans ; chemistry ; standards ; Glucosides ; chemistry ; standards ; Hydrogen-Ion Concentration ; Intestinal Absorption ; drug effects ; Kinetics ; Lignans ; chemistry ; standards ; Male ; Quality Control ; Rats ; Rats, Wistar ; Verapamil ; pharmacology

OBJECTIVETo investigate the absorption and transport mechanism of magnolol in Caco-2 cell model.

METHODSA human intestinal epithelial cell model Caco-2 cell in vitro cultured was applied to study the absorption and transport of magnolol, the effects of time, donor concentration, P-gp inhibitor verapamil, pH and temperature on the absorption and transport of magnolol were investigated. The determination of magnolol was performed by high performance liquid chromatography, then the values of apparent permeability coefficient (P app ) and P ratio Basolateral-to-Apical (BL-to-AP)/Apical-to-Basolateral (AP-to-BL) were calculated.

RESULTSIn Caco-2 cell model, comparing the amounts of transport of AP-to-BL and BL-to-AP, the latter was larger. At the same donor concentration, either the amounts of transport of AP-to-BL or BL-to-AP increased with increase in donor concentration and incubation time. Verapamil could significantly improve the amounts of transport of AP-to-BL. The transport of AP-to-BL and BL-to-AP depended on temperature, and there was no significant effect of pH on the transport of AP-to-BL.

CONCLUSIONMagnolol could be transported through the intestinal mucosa via a passive diffusion mechanism primarily, coexisting with a carrier-mediated transport, at the same time, the efflux mechanism could be involved.

Biological Transport ; drug effects ; Biphenyl Compounds ; metabolism ; Caco-2 Cells ; Chromatography, High Pressure Liquid ; Humans ; Hydrogen-Ion Concentration ; drug effects ; Intestinal Absorption ; drug effects ; Lignans ; metabolism ; Models, Biological ; Temperature ; Time Factors ; Verapamil ; pharmacology

OBJECTIVETo observe the uptake of tiliani in Caco-2 Cell.

METHODA human intestinal epithelial cell model Caco-2 cell in vitro cultured was applied to study the kinetics of uptake, transport and efflux kinetics of tiliani at small intestine. The effect of time, pH, drug concentration and inhibitors on the uptake of tiliani were investigated. The determination of tiliani was performed by HPLC.

RESULTTiliani in Caco-2 cell uptake was time-dependent. Tiliani in Caco-2 cell uptake was concentration-dependent at 4-16 mg x L(-1) consistent with passive diffusion process. The acid condition was good for the uptake of tiliani at pH 5-8. Compared with the control group, tiliani cell uptake was significantly higher after additional treatmeant with verapamil (1.545 +/- 0.010) mg x g(-1), (P < 0.05), and tiliani cell uptake was significantly lower after additional treatmeanet with sodium azide (0.994 +/- 0.003) mg x g(-1) (P < 0.05), with 2,4-dinitrophenol (1.174 +/- 0.030) mg x g(-1) (P < 0.05), and with phloridzin (1.098 +/- 0.021) mg x g(-1) (P < 0.05). Compared with the control group, tiliani cell uptake was not significantly after additional treatmeant with lactose (1.470 +/- 0.025) mg x g(-1), Papp of Basolateral to Apical was much more than that of Apical to Basolateral (1.10 Fold).

CONCLUSIONP-glycoproteins and SGLT1 participate in the conveying process of tiliani in Caco-2 cells. The uptake of tiliani has no relationship to LPH. passive transport and carrier-mediated transport participate in the uptake process of tiliani in Caco-2 cells.

Biological Transport ; drug effects ; Caco-2 Cells ; Chromatography, High Pressure Liquid ; Flavonoids ; pharmacokinetics ; Glycosides ; pharmacokinetics ; Humans ; Intestinal Absorption ; Kinetics ; Verapamil ; pharmacology