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OBJECTIVE:To establish the pharmacokinetic-pharmacodynamic(PK-PD) model of Nisoldipine controlled-release patches(NCRP)in spontaneously hypertensive rats(SHR). METHODS:SHR were randomized into a patch(NCRP)group and a tablet(Nisoldipine tablets)group,with 6 rats in each group. The microdialysis probes were implanted in SHR. Each rat was given 5 mg nisoldipine. Plasma microdialysate was collected within 36 h after administration. HPLC was adopted to determine the plasma concentration of nisoldipine,and WinNonlin 5.3 was employed to calculate Pharmacokinetic parameters. With heart rate and blood pressure as pharmacodynamic indexes,PK-PD model study was conducted. RESULTS:Vs. nisoldipine tablets,NCRP has con-trolled release effect. The relationship between NCRP drug effect and effect-site concentration met the Sigmoid-Emax model. The main parameters of the PK-PD model for heart rate and systolic blood pressure were as follows as Emax of (2.65 ± 0.06) and (10.71 ± 0.87),EC50 of (83.65 ± 35.25) and (1.29 ± 0.26) ng/ml,γ of (0.83 ± 0.91) and (1.2 ± 0.35),Keo of (0.37 ± 0.53) and (0.91±0.24)h-1. CONCLUSIONS:PK-PD model of NCRP in SHR has been established successfully.
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Objective:To establish a dissolution determination method for nisoldipine tablets. Methods: The detection was car-ried out according to the second method described in ChP VolumeⅡappendix XC. The medium was 600 ml hydrochloric acid solution (0. 1 mol·L-1 ) containing 0. 05% SDS, the rotation speed was 75 r·min-1 , and the UV detection wavelength was at 238nm. Re-sults:The linear range of nisoldipine was 4-14 μg·ml-1(r=0. 999 9),and the average recovery was 100. 5%(RSD=1. 1%, n=9). Conclusion:The method is simple, accurate and reliable, and can be used in the dissolution determination of nisoldipine tablets.
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Nisoldipine is used for treatment of hypertension and angina pectoris. However, it suffers from very low bioavailability due to its extensive pre-systemic metabolism. This together with its low dose made it excellent candidate for transdermal delivery. Accordingly, the aim of this study was to develop and evaluate transdermal delivery system for optimization of nisoldipine skin permeability. Proniosomes comprising cholesterol and span 60 with different ratios together with ethanol and minimal water were evaluated for such aim. The developed formulations were assessed with respect to drug entrapment efficiency, viscosity, in vitro drug release and transdermal permeability. All proniosomal formulations have significantly enhanced transdermal delivery of nisoldipine compared with saturated aqueous solution of the drug. Increasing cholesterol content resulted in reduced drug flux. The study was extended to compare the efficacy of such proniosomes to the corresponding niosomes. Proniosomes significantly optimized transdermal delivery of nisoldipine compared to their hydrated form. Such results contradict the hypothesis which claimed the necessity for niosome formation from proniosomes for efficient transdermal delivery with penetration enhancement being mainly responsible for improved delivery.
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Objective To investigate the influences of polyethylene glycol on the solubility and in vitro dissolution of m-nisoldipine,which could provide guidance for chosing formulations of m-nisoldipine. Methods Solid dispersions of m-nisoldipine were prepared by solvent-melting method with polyethylene glycol6000 matrix. DSC and XRD spectroscopy were applied to identify the solid dispersions. The solubility and in vitro dissolution were detected by UV spectroscopy. Results The DSC and XRD map were different from the crude drug and their physical mixtures. The dissolution rates(13,15,17) were faster(35. 31%,38. 71%,41. 48%) than that of the crude drug(26. 80%),and the dissolution rates of the solid dispersions in the same ratio were higher than the physical mixtures. Conclusion DSC analysis indicated that eutectic compounds were produced by the m-nisoldipine and polyethylene glycol,in which polyethylene glycol6000 acts as a carrier. The solubility and in vitro dissolution of m-nisoldipine can be increased.
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This study is to explore the activation of the Ca2+/CaM/CaN signal pathway in 5-HT-induced proliferation of rat pulmonary artery smooth muscle cells (PASMCs) and the inhibitory effect of m-nisoldipine (m-Nis) on this pathway. PASMCs were cultured with the explant technique. The proliferation of PASMCs was evaluated by MTT assay. Confocal microscopy was used to measure the change of [Ca2+]i. The mRNA expression of CaM and CaN was evaluated by RT-PCR and the activity of CaN was measured according to the instruction of kits. The results of MTT assay suggested that 5-HT (1 ?mol?L-1) significantly induced the proliferation of rat PASMCs (P
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Aim To explore the effect of m-Nisoldipine(m-Nis) on 5-HT-induced proliferation,migration of rat PASMCs and to study the mechanisms.Methods PASMCs were cultured with the explant technique,and were divided into 6 groups:control group,5-HT(1 μmol·L~(-1)) group and m-Nis(10~(-5),10~(-6),10~(-7),10~(-8) mol·L~(-1))group.MTT assay was used to evaluate the proliferation of PASMCs,and transwell chambers were used to detect the migration of PASMCs.In addition,the expression of PCNA and the phosphorylation of ERK1/2 were evaluated by Western blot analysis.Results m-Nis inhibited the proliferation(P<0.05 or P<0.01)and migration(P<0.01)of rat PASMCs induced by 5-HT obviously.Similarly,Western blot analysis of PCNA indicated that the expression of PCNA was significantly higher in 5-HT group than that in control group(P<0.01).Whereas,in four m-Nis treated groups,the level of PCNA was markedly decreased(P<0.05 or P<0.01).Meanwhile,m-Nis 10~(-5),10~(-6) and 10~(-7) mol·L~(-1) pretreatment also reduced 5-HT-induced phosphorylation of ERK1/2 obviously(P<0.05 or P<0.01).Conclusion m-Nis inhibits 5-HT-induced proliferation and migration of rat PASMCs obviously,which may be related to the inhibition of PCNA expression and the blockage of ERK1/2/MAPK signal pathway.
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OBJECTIVE:To optimize the formulation of nisoldipine buccal adhesive tablets. METHODS: The formulation was optimized by orthogonal design with the dosage ratio of carbopol to chitosan in drug-containing layer and protection layer, the content of lactose and the tabletting hardness as factors. The bioadhesiveness and in vitro drug release rate of the tablets was measured as well. RESULTS: The optimal formulation was as follows: the ratio of carbopol to chitosan in drug-containing layer and protection layer were 22.5∶22.5 and 33.3∶16.7 mg, respectively; the dosage of lactose was 10 mg, and tabletting hardness was 5 kg. The averge bioadhesiveness of 3 bacthes of optimized preparations was 79.5 g?cm-2, and the average in vitro drug release rate of the tablets in 12 h was more than 95%. CONCLUSIONS: The optimized nisoldipine buccal adhesive tablets enjoy ideal bioadhesiveness and slow-release character.
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OBJECTIVE:To prepare m-nisoldipine solid dispersion from poorly-soluble m-nisoldipine so as to improve its solubility and dissolution rate in vitro. METHODS: Solid dispersions of m-nisoldipine were prepared by coprecipitation method with poloxamer as carrier; Differential scanning calorimetry (DSC) was used to determine the status of nimodipine in carrier. The solubility and the dissolution rate of the solid dispersion in vitro were studied. RESULTS: DSC analysis indicated that eutectic mixture was formed from m-nisoldipine and poloxamer. The solubility of m-nisoldipine and the its solid dispersions prepared from m-nisoldipine and poloxamer at different ratio (1∶3, 1∶5, 1∶7) were 0.89, 4.50, 15.35, and 23.03 mg?L-1, respectively, and their 120 min dissolution rates were 26.80%, 38.57%, 41.38%, and 45.92%, respectively. In the same ratio, the dissolution rates of the solid dispersions were higher than those of their physics mixtures. CONCLUSIONS: The solid dispersion of m-nisoldipine prepared with poloxamer as carrier can increase the solubility and dissolution rate in vitro.
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OBJECTIVE:To study the relative bioavailability,pharmacokinetics and bioequivalence of domestic nisoldipine tablets in healthy volunteers.METHODS:A single oral dose of 10 mg test and reference nisoldipine tablets were given to 24 male healthy volunteers in an open randomized 2?2 latin square design.The plasma concentrations of nisoldipine at different time points were determined by LC-MS and the pharmacokinetic parameters of the two kinds of tablets were computed and their bioequiavailability was evaluated.RESULTS:The main pharmacokinetic parameters of the test vs.reference formulations of nisoldipine in 24 healthy volunteers were as follows:Cmax(2.94?2.78)ng?mL-1 vs.(3.22?2.16)ng?mL-1,tmax(1.70?1.00)h vs.(1.40?1.00)h,t1/2(6.81?4.11)h vs.(5.55?2.35)h,AUC0～24(10.60?7.70)ng?h?mL-1 vs.(9.90?6.76)ng?h?mL-1,AUC0～∞(11.30?7.90)ng?h?mL-1 vs.(10.20?7.00)ng?h?mL-1.The relative bioavailability of domestic nisoldipine tablets was(110.3?30.8)%.CONCLUSION:The reference preparation and the test preparation of nisoldipine tablets were proved to be bioequivalent.
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AIM: To determine the concentration of nisoldipine in human plasma by HPLC-MS method and investigate the pharmacokinetics of sustained and immediate-release preparations. METHODS: A C 18 column was used to separate nisoldipine from plasma with the mobile phase of a mixture of methanol-water-acetic acid (7525 0.1) at a flow rate of 1.0 ml?min -1. MS: atmospheric pressure electronic spray ionization (AP-ESI) and ion mass spectral (m/z) of 411 were selected to quantify nisoldipine. Internal standard (IS): atmospheric pressure electronic spray ionization and m/z of 441 for nimodipine. RESULTS: The linear range of the standard curve of nisoldipine was 0.2- 50 ?g?L -1 and the determination limit was 0.15 ?g?L -1. The recovery rate was more than 70%, and intra-day relative standard deviation (RSD) and inter-day RSD were less than 10%. After being given a single dose of 10 mg nisoldipine sustained release tablet, sustained release capsule and normal tablet, the half life(t 1/2 /h) were 6.08? 1.48, 7.06? 1.80 and 3.70? 0.25, the time to peak concentration (T peak /h) were 5.4? 0.7, 5.8? 0.4 and 2.0? 0.2, the peak concentration (C max / ?g?L -1) were 3.43? 0.55, 3.71? 0.24 and 9.18? 3.78, the area under time- concentration curve (AUC 0-t / ?g?h -1?L -1) were 31.10? 5.00, 33.63? 7.16 and 32.72? 5.09. But after being given multiple doses of nisoldipine, C max/ ?g?L -1 were 5.20? 0.27, 3.91? 0.22 and 5.30? 1.04, C min / ?g?L -1 were 0.72? 0.10, 0.77? 0.07 and 0.53? 0.07, DF were 175.00%? 16.34%, 177.10%? 18.43% and 247.92%? 57.71% respectively. The bioavailability of sustained- release tablet and capsule were 96%?12% and 102%?9% respectively. CONCLUSION: The determination of concentration of nisoldipine in human plasma by HPLC-MS method is sensitive and accurate. It can be used for the investigation of the bioavailability and pharmacokinetic of nisoldipine.
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m-Nisoldipine ( m-Nis ) , isobutyl methyl 1 , 4-dihydro - 2, 6-dimethyl-4-( 3-nitrophenyl )-3 , 5-pyridine dicarboxylate, is a new calcium antagonist. Its effects on hemodynamics and regional blood flow as well as the distribution of cardiac output were evaluated in comparison with Nis with radio-biomicrospheres in conscious rabbits. ( 1 ) m-Nis ( 1 ?g/kg ? min-1 ? 10 min, iv ) increased cardiac output and cardiac index significantly (P0.05) ; ( 2 ) m-Nis increased stroke volume and left ventricular systolic work ( per beat ) while Nis slightly increased the former and decreased the later, and these differences were statistically significant (P