OBJECTIVE: To investigate the effects of tetrandrine (Tet) on proliferation and activation of rat cardiac fibroblasts. METHODS: Firstly, the cell counting kit-8 (cck-8) assay was applied to detect the effects of Tet with different concentrations on proliferation of cardiac fibroblasts. Secondly, transforming growth factor (TGF-β)with a concentration of 5 μg/L was used to induce the cardiac fibroblast activation, and Western blot was performed to measure the expression variation of β-catenin, vimentin (Vm), fibronectin (Fn) and smooth muscle α-actin (SMA). At last, the real-time PCR was conducted to measure the expression change of collagen-1(Col-1) and collagen-3(Col-3). RESULTS: The cck-8 assay showed that the Tet with different concentrations respectively, which were 0.5 μmol/L, 1 μmol/L, 2 μmol/L, 4 μmol/L, and 8 μmol/L, significantly inhibited the proliferation of cardiac fibroblasts. The viability was decreased to 94.4%,84.9%,74.9%,63.8%and 50.3% respectively of the control group when the Tet concentration changed, and the difference was statistically significant, P=0.043, P<0.001, P<0.001, P<0.001, P<0.001 respectively. Western blot revealed that the expressions of β-catenin, Fn, SMA and Vm, were up-regulated by TGF-β(5 μg/L), the result showed that the difference was statistically significant, and the P values were 0.001,0.008,0.010,0.001 respectively. Then, the up-regulation of β-catenin, Fn and SMA was attenuated by pre-treatment of Tet, and the result also displayed that the difference was statistically significant, and the P values were 0.009, 0.005, 0.019,respectively. While there was no significant change in the expression of Vm, according to Western blotting, and P>0.05,at the same time, real-time PCR indicated that the up-regulations of Col-1 and Col-3 which were induced by TGF-β were blocked by pre-treatment of Tet, the result showed that the difference was statistically significant, P<0.001. CONCLUSION According to the experimental results, we can draw the conclusion that: the Tet can significantly inhibit the proliferation of cardiac fibroblasts, meanwhile, it can block the activation of cardiac fibroblasts, which is induced by TGF-β. It is supposed that the Tet may probably have anti myocardial fibrosis, which indicates that it may probably be a medicine which is used to block the cardiac remodeling.
Actins ; Animals ; Benzylisoquinolines/pharmacology* ; Blotting, Western ; Calcium Channel Blockers/pharmacology* ; Cell Proliferation ; Collagen ; Collagen Type I ; Fibroblasts/physiology* ; Fibrosis ; Myocardium/cytology* ; Neoplasm Proteins/metabolism* ; Rats ; Signal Transduction ; Transforming Growth Factor beta/metabolism* ; Transforming Growth Factor beta1

This study aims to validate our hypothesis that acid-sensing ion channels (ASICs) may contribute to the symptom of pain in patients with chronic prostatitis (CP). We first established a CP rat model, then isolated the L5-S2 spinal dorsal horn neurons for further studies. ASIC1a was knocked down and its effects on the expression of neurogenic inflammation-related factors in the dorsal horn neurons of rat spinal cord were evaluated. The effect of ASIC1a on the Ca²⁺ ion concentration in the dorsal horn neurons of rat spinal cord was measured by the intracellular calcium ([Ca²⁺]i) intensity. The effect of ASIC1a on the p38/mitogen-activated protein kinase (MAPK) signaling pathway was also determined. ASIC1a was significantly upregulated in the CP rat model as compared with control rats. Acid-induced ASIC1a expression increased [Ca²⁺]i intensity in the dorsal horn neurons of rat spinal cord. ASIC1a also increased the levels of neurogenic inflammation-related factors and p-p38 expression in the acid-treated dorsal horn neurons. Notably, ASIC1a knockdown significantly decreased the expression of pro-inflammatory cytokines. Furthermore, the levels of p-p38 and pro-inflammatory cytokines in acid-treated dorsal horn neurons were significantly decreased in the presence of PcTx-1, BAPTA-AM, or SB203580. Our results showed that ASIC1a may contribute to the symptom of pain in patients with CP, at least partially, by regulating the p38/MAPK signaling pathway.
Acid Sensing Ion Channel Blockers/pharmacology* ; Acid Sensing Ion Channels/genetics* ; Animals ; Calcium/metabolism* ; Chelating Agents/pharmacology* ; Chronic Disease ; Cytokines/metabolism* ; Disease Models, Animal ; Egtazic Acid/pharmacology* ; Gene Knockdown Techniques ; Imidazoles/pharmacology* ; Inflammation/metabolism* ; MAP Kinase Signaling System/genetics* ; Male ; Pain/genetics* ; Peptides/pharmacology* ; Phosphorylation/drug effects* ; Posterior Horn Cells/metabolism* ; Prostatitis/complications* ; Protein Kinase Inhibitors/pharmacology* ; Pyridines/pharmacology* ; Rats ; Spider Venoms/pharmacology* ; Up-Regulation ; p38 Mitogen-Activated Protein Kinases/metabolism*

OBJECTIVETo investigate the rebound depolarization of substantia gelatinosa (SG) neurons in rat spinal dorsal horn and explore its modulatory mechanisms to provide better insights into rebound depolarization-related diseases.

METHODSParasagittal slices of the spinal cord were prepared from 3- to 5-week-old Sprague-Dawley rats. The electrophysiologic characteristics and responses to hyperpolarization stimulation were recorded using whole-cell patch-clamp technique. The effects of hyperpolarization-activated cyclic nucleotide gated cation (HCN) channel blockers and T-type calcium channel blockers on rebound depolarization of the neurons were studied.

RESULTSA total of 63 SG neurons were recorded. Among them, 23 neurons showed no rebound depolarization, 19 neurons showed rebound depolarization without spikes, and 21 neurons showed rebound depolarization with spikes. The action potential thresholds of the neurons without rebound depolarization were significantly higher than those of the neurons with rebound depolarization and spikes (-28.7∓1.6 mV vs -36.0∓2.0 mV, P<0.05). The two HCN channel blockers CsCl and ZD7288 significantly delayed the latency of rebound depolarization with spike from 45.9∓11.6 ms to 121.6∓51.3 ms (P<0.05) and from 36.2∓10.3 ms to 73.6∓13.6 ms (P<0.05), respectively. ZD7288 also significantly prolonged the latency of rebound depolarization without spike from 71.9∓35.1 ms to 267.0∓68.8 ms (P<0.05). The T-type calcium channel blockers NiCl2 and mibefradil strongly decreased the amplitude of rebound depolarization with spike from 19.9∓6.3 mV to 9.5∓4.5 mV (P<0.05) and from 26.1∓9.4 mV to 15.5∓5.0 mV (P<0.05), respectively. Mibefradil also significantly decreased the amplitude of rebound depolarization without spike from 14.3∓3.0 mV to 7.9∓2.0 mV (P<0.05).

CONCLUSIONNearly two-thirds of the SG neurons have rebound depolarizations modulated by HCN channel and T-type calcium channel.

Action Potentials ; Animals ; Calcium Channel Blockers ; pharmacology ; Calcium Channels, T-Type ; Cell Polarity ; Cesium ; pharmacology ; Chlorides ; pharmacology ; Cyclic Nucleotide-Gated Cation Channels ; antagonists & inhibitors ; Neurons ; cytology ; Patch-Clamp Techniques ; Pyrimidines ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Spinal Cord Dorsal Horn ; cytology ; Substantia Gelatinosa ; cytology

BACKGROUNDRenin-angiotensin system inhibitor and calcium channel blocker (CCB) are widely used in controlling blood pressure (BP) in patients with chronic kidney disease (CKD). We carried out a meta-analysis to compare the renoprotective effect of the combination of angiotensin-converting enzyme inhibitor (ACEI) or angiotensin receptor blocker (ARB) and CCB (i.e., ACEI/ARB + CCB) with ACEI/ARB monotherapy in patients with hypertension and CKD.

METHODSPublications were identified from PubMed, Embase, Medline, and Cochrane databases. Only randomized controlled trials (RCTs) of BP lowering treatment for patients with hypertension and CKD were considered. The outcomes of end-stage renal disease (ESRD), cardiovascular events, BP, urinary protein measures, estimated glomerular filtration rate (GFR), and adverse events were extracted.

RESULTSBased on seven RCTs with 628 patients, ACEI/ARB + CCB did not show additional benefit for the incidence of ESRD (risk ratio [RR] = 0.84; 95% confidence interval [CI]: 0.52-1.33) and cardiovascular events (RR = 0.58; 95% CI: 0.21-1.63) significantly, compared with ACEI/ARB monotherapy. There were no significant differences in change from baseline to the end points in diastolic BP (weighted mean difference [WMD] = -1.28 mmHg; 95% CI: -3.18 to -0.62), proteinuria (standard mean difference = -0.55; 95% CI: -1.41 to -0.30), GFR (WMD = -0.32 ml/min; 95% CI: -1.53 to -0.89), and occurrence of adverse events (RR = 1.05; 95% CI: 0.72-1.53). However, ACEI/ARB + CCB showed a greater reduction in systolic BP (WMD = -4.46 mmHg; 95% CI: -6.95 to -1.97), compared with ACEI/ARB monotherapy.

CONCLUSIONACEI/ARB + CCB had no additional renoprotective benefit beyond than what could be achieved with ACEI/ARB monotherapy.

Angiotensin Receptor Antagonists ; pharmacology ; therapeutic use ; Angiotensin-Converting Enzyme Inhibitors ; pharmacology ; therapeutic use ; Calcium Channel Blockers ; pharmacology ; therapeutic use ; Drug Therapy, Combination ; Glomerular Filtration Rate ; Humans ; Hypertension ; drug therapy ; Kidney ; drug effects ; Renal Insufficiency, Chronic ; drug therapy

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

This study was amid to construct the pharmacophore model of L-type calcium channel antagonist in the application of screening Drugbank and TCMD. This paper repositions the approved drugs resulting from virtual screening and discusses the relocation-based drug discovery methods, screening antihypertensive drugs with L-type calcium channel function from TCMD. Qualitative hypotheses wre generated by HipHop separately on the basis of 12 compounds with antagonistic action on L-type calcium channel expressed in rabbit cardiac muscle. Datebase searching method was used to evaluate the generated hypotheses. The optimum hypothesis was used to search Drugbank and TCMD. This paper repositions the approved drugs and evaluates the antihypertensive effect of the chemical constituent of traditional Chinese medicine resulting from virtual screening by the matching score and literature. The results showed that optimum qualitative hypothesis is with six features, which were two hydrogen-bond acceptors, four hydrophobic groups, and the CAI value of 2.78. Screening Drugbank achieves 93 approved drugs. Screening TCMD achieves 285 chemical constituents of traditional Chinese medicine. It was concluded that the hypothesis is reliable and can be used to screen datebase. The approved drugs resulting from virtual screening, such as pravastatin, are potentially L-type calcium channels inhibitors. The chemical constituents of traditional Chinese medicine, such as Arctigenin III and Arctigenin are potentially antihypertensive drugs. It indicates that Drug Repositioning based on hypothesis is possible.
Animals ; Antihypertensive Agents ; chemistry ; pharmacology ; Calcium Channel Blockers ; chemistry ; pharmacology ; Calcium Channels, L-Type ; genetics ; metabolism ; Drug Repositioning ; methods ; Molecular Structure ; Myocardium ; metabolism ; Rabbits

The purpose of the current study was to examine the pharmacokinetic profiles and tissue distribution of clevidipine, an ultra-short-acting calcium antagonist in Beagle dogs and Sprague-Dawley rats, respectively. The pharmacokinetics and biodistribution of its primary metabolite H152/81 were also evaluated. Dogs received intravenous infusion of clevidipine at a dose rate of 17 μg/(kg·min), and rats were given intravenous administration of clevidipine at a dose of 5 mg/kg. Dog plasma and rat tissues were collected and assayed by HPLC-MS/MS. It was found that plasma clevidipine quickly reached the steady state concentration. The terminal half-life was short (16.8 min), pointing out a rapid elimination after the end of the infusion. The total clearance was 5 mL/(min·kg). In comparison, plasma concentration of H152/81 was increased more slowly and was significantly higher than that of clevidipine. After intravenous administration, clevidipine was distributed rapidly into all tissues examined, with the highest concentrations found in the brain, heart and liver. Maximal concentrations of clevidipine were found in most tissues at 10 min post-dosing. However, the proportion of clevidipine distributed in all tissues was quite small (0.042‰) compared to the total administration dose. It was suggested that clevidipine was mainly distributed in blood and it transformed to inactive metabolite rapidly.
Animals ; Calcium Channel Blockers ; pharmacokinetics ; pharmacology ; Dogs ; Dose-Response Relationship, Drug ; Organ Specificity ; drug effects ; Pyridines ; pharmacokinetics ; pharmacology ; Rats

Serotonin (5-hydroxytryptamine (5-HT)) is a neurotransmitter that regulates a variety of functions in the nervous, gastrointestinal and cardiovascular systems. Despite such importance, 5-HT signaling pathways are not entirely clear. We demonstrated previously that 4-aminopyridine (4-AP)-sensitive voltage-gated K+ (Kv) channels determine the resting membrane potential of arterial smooth muscle cells and that the Kv channels are inhibited by 5-HT, which depolarizes the membranes. Therefore, we hypothesized that 5-HT contracts arteries by inhibiting Kv channels. Here we studied 5-HT signaling and the detailed role of Kv currents in rat mesenteric arteries using patch-clamp and isometric tension measurements. Our data showed that inhibiting 4-AP-sensitive Kv channels contracted arterial rings, whereas inhibiting Ca2+-activated K+, inward rectifier K+ and ATP-sensitive K+ channels had little effect on arterial contraction, indicating a central role of Kv channels in the regulation of resting arterial tone. 5-HT-induced arterial contraction decreased significantly in the presence of high KCl or the voltage-gated Ca2+ channel (VGCC) inhibitor nifedipine, indicating that membrane depolarization and the consequent activation of VGCCs mediate the 5-HT-induced vasoconstriction. The effects of 5-HT on Kv currents and arterial contraction were markedly prevented by the 5-HT2A receptor antagonists ketanserin and spiperone. Consistently, alpha-methyl 5-HT, a 5-HT2 receptor agonist, mimicked the 5-HT action on Kv channels. Pretreatment with a Src tyrosine kinase inhibitor, 4-amino-5-(4-chlorophenyl)-7-(t-butyl)pyrazolo[3,4-d]pyrimidine, prevented both the 5-HT-mediated vasoconstriction and Kv current inhibition. Our data suggest that 4-AP-sensitive Kv channels are the primary regulator of the resting tone in rat mesenteric arteries. 5-HT constricts the arteries by inhibiting Kv channels via the 5-HT2A receptor and Src tyrosine kinase pathway.
4-Aminopyridine/pharmacology ; Action Potentials ; Animals ; Calcium Channel Blockers/pharmacology ; Calcium Channels/metabolism ; Cells, Cultured ; Ketanserin/pharmacology ; Male ; Mesenteric Arteries/drug effects/*metabolism/physiology ; Muscle Contraction ; Muscle, Smooth, Vascular/cytology/drug effects/metabolism/physiology ; Myocytes, Smooth Muscle/drug effects/metabolism/physiology ; Nifedipine/pharmacology ; Potassium Channel Blockers/pharmacology ; Potassium Channels, Voltage-Gated/antagonists & inhibitors/*metabolism ; Protein Kinase Inhibitors/pharmacology ; Rats ; Rats, Sprague-Dawley ; Receptor, Serotonin, 5-HT2A/*metabolism ; Serotonin/*pharmacology ; Serotonin 5-HT2 Receptor Antagonists/pharmacology ; Spiperone/pharmacology ; *Vasoconstriction ; src-Family Kinases/antagonists & inhibitors/*metabolism

OBJECTIVETo explore the modulatory effect of niflumic acid and blocker of calcium channel on the desensitization of gamma aminobutyric acid (GABA)-activated currents in dorsal root ganglion(DRG) neurons from rat.

METHODSThe whole-cell patch-clamp technique was used to observe the modulatory effect of niflumic acid and blocker of calcium channel on the desensitization of GABA-activated currents in neurons freshly dissociated from rat DRG neurons.

RESULTSApplication of GABA (0.1-1 000 micromol/L) could induce concentration-dependent inward currents in some cells (212/223, 95.11%). GABA-(100 micromol/L) activated currents was (1.32 +/- 0.74) nA (n = 84). However, pre-application of niflumic acid (1-100 micromol/L) and nitrendipine (specific blocker of L-calcium channel)(0.1-30 micromol/L) could inhibit the GABA-activated inward current which was identified to be GABAA receptor-mediated current. The inhibitory effects of niflumic acid and nitrendipine were concentration-dependent. The suppression rate of 10 micromol/L niflumic acid and nitrendipine to GABA-activated currents were (31.60% +/- 4.87%) (n = 19) and (43.60% < or = 5.10%) (n = 5), respectively. The desensitization of GABA-activated currents had double exponential characteristic. Tau value was (14.68 +/- 5.11) s (n = 6) and (175.8 +/- 42.67) s (n = 6, r = 0.9647), respectively. Pre-application of niflumic acid (100 micromol/L) and nickel chloride (nonspecific blocker of L-calcium channel) (100 micromol/L) altered tau value of the desensitization of GABA-activated currents, tau value reduced for (4.64 +/- 2.21) s (n = 3), (43.70 +/- 14.34) s ( n = 3, r = 0.9548) and (4.64 +/- 2.21) s (n = 3), (43.70 +/- 14.34) s (n = 3, r = 0.9721).

CONCLUSIONPre-application of niflumic acid exerts a more strong inhibitory effect on the peak value of GABA-activated current, which possibly is through blocking the calcium-activated chloride ion channel to accelerate the desensitization of GABA-activated currents.

Animals ; Animals, Newborn ; Calcium Channel Blockers ; pharmacology ; Calcium Channels, L-Type ; drug effects ; Ganglia, Spinal ; drug effects ; physiology ; Membrane Potentials ; drug effects ; physiology ; Neurons ; drug effects ; physiology ; Niflumic Acid ; pharmacology ; Nitrendipine ; pharmacology ; Patch-Clamp Techniques ; Rats ; Rats, Sprague-Dawley ; gamma-Aminobutyric Acid ; pharmacology

The roles of intermediate conductance Ca(2+)-activated K(+) channel (IKCa1) in the pathogenesis of hepatocellular carcinoma (HCC) were investigated. Immunohistochemistry and Western blotting were used to detect the expression of IKCa1 protein in 50 HCC and 20 para-carcinoma tissue samples. Real-time PCR was used to detect the transcription level of IKCa1 mRNA in 13 HCC and 11 para-carcinoma tissue samples. The MTT assay was used to measure the function of IKCa1 in human HCC cell line HepG2 in vitro. TRAM-34, a specific blocker of IKCa1, was used to intervene with the function of IKCa1. As compared with para-carcinoma tissue, an over-expression of IKCa1 protein was detected in HCC tissue samples (P<0.05). The mRNA expression level of IKCa1 in HCC tissues was 2.17 times higher than that in para-carcinoma tissues. The proliferation of HepG2 cells was suppressed by TRAM-34 (0.5, 1.0, 2.0 and 4.0 μmol/L) in vitro (P<0.05). Our results suggested that IKCa1 may play a role in the proliferation of human HCC, and IKCa1 blockers may represent a potential therapeutic strategy for HCC.
Calcium Channel Blockers ; pharmacology ; Carcinoma, Hepatocellular ; pathology ; physiopathology ; Cell Proliferation ; drug effects ; Hep G2 Cells ; Humans ; Intermediate-Conductance Calcium-Activated Potassium Channels ; antagonists & inhibitors ; metabolism ; Ion Channel Gating ; drug effects ; Liver Neoplasms ; pathology ; physiopathology ; Potassium ; metabolism ; Pyrazoles ; pharmacology ; Tumor Cells, Cultured