Interaction of procainamide hydrochloride(PAH) with human serum albumin(HSA) is of great significance in understanding the pharmacokinetic and pharmacodynamic mechanisms of the drug. Multi-spectroscopic techniques...Interaction of procainamide hydrochloride(PAH) with human serum albumin(HSA) is of great significance in understanding the pharmacokinetic and pharmacodynamic mechanisms of the drug. Multi-spectroscopic techniques were used to investigate the binding mode of PAH to HSA and results revealed the presence of static type of quenching mechanism. The number of binding sites, binding constants and thermodynamic parameters were calculated. The results showed a spontaneous binding of PAH to HSA and hydrophobic interactions played a major role. In addition, the distance between PAH and the Trp–214 was estimated employing the F?rster's theory. Site marker competitive experiments indicated that the binding of PAH to HSA primarily took place in subdomain IIA(Sudlow's site I). The influence of interference of some common metal ions on the binding of PAH to HSA was studied. Synchronous fluorescence spectra(SFS), 3D fluorescence spectra and circular dichroism(CD) results indicated the conformational changes in the structure of HSA.展开更多
Turbidimetry and radioimmunoassay were used to study the effects of procainamide (PA ) onadenosine diphosphate (ADP)-induced rabbit platelet aggregation and thromboxane B2 (TXB2) production invitro. PA 8. 5--544. 0 μ...Turbidimetry and radioimmunoassay were used to study the effects of procainamide (PA ) onadenosine diphosphate (ADP)-induced rabbit platelet aggregation and thromboxane B2 (TXB2) production invitro. PA 8. 5--544. 0 μmol L-1 inhibited ADP-induced platelet aggregation and TXB2 production, and theinhibition rates were 26. 7% -- 66. 7 % and 21. 4 % -- 70. 1 %, respectively. There was positive correlation between PA concentration and its efficiency in inhibiting the platelet aggregation and TXB2 production, and alsobetween the inhibition rates of platelet aggregation and that of TXB2 production. The three linear equationsand main parameters were The results indicate that PA could significantly inhibit ADP--induced platelet aggregation and TXB2 production in rabbits.展开更多
Objective:To test the effect of voltage-gated sodium channels (VGSCs) blockers on the motility and viability of human spermin-vitro and to evaluate the tested compounds as potential contact spermicidal.Methods: Sperm ...Objective:To test the effect of voltage-gated sodium channels (VGSCs) blockers on the motility and viability of human spermin-vitro and to evaluate the tested compounds as potential contact spermicidal.Methods: Sperm samples were obtained from healthy non-smoking volunteers of age 25-30 years who had not taken any drug 3 months before and during the course of the study. The effect of VGSCs blockers evaluated from two pharmacological classes including antiarrhythmic (amiodarone, procainamide and disopyramide) and antiepileptic (carbamazepine, oxcarbazepine, phenytoin, and lamotrigine) drugs. They were tested on thein-vitro motility and viability of human sperm using Computer Assisted Semen Analyzer.Results:All tested drugs except oxcarbazepine showed dose dependent inhibition of total motility with significant reduction (P<0.05) at the maximum concentration of 200 μM when compared with the control. The concentrations of drugs that reduced total sperm motility to 50% of control (half maximal inhibitory concentration) were 2.76, 14.16 and 20.29 μM for phenytoin, lamotrigine and carbamazepine, respectively;and 2.53, 5.32 and 0.37 μM for amiodarone, procainamide and disopyramide, respectively. The anti-motility effects were reversible to various degrees. There was statistically insignificant difference in the inhibition of sperm viability among amiodarone, procainamide and disopyramide. Phenytoin demonstrated the most potent spermicidal action.Conclusions:VGSCs blockers have significant adverse effects onin-vitro motility of human spermatozoa. Soin-vivo studies are required to determine their potential toxicological effects on human semen quality, which is an important factor regarding fertility. Moreover, these drugs have the potential to be developed into contact spermicidal.展开更多
文摘Interaction of procainamide hydrochloride(PAH) with human serum albumin(HSA) is of great significance in understanding the pharmacokinetic and pharmacodynamic mechanisms of the drug. Multi-spectroscopic techniques were used to investigate the binding mode of PAH to HSA and results revealed the presence of static type of quenching mechanism. The number of binding sites, binding constants and thermodynamic parameters were calculated. The results showed a spontaneous binding of PAH to HSA and hydrophobic interactions played a major role. In addition, the distance between PAH and the Trp–214 was estimated employing the F?rster's theory. Site marker competitive experiments indicated that the binding of PAH to HSA primarily took place in subdomain IIA(Sudlow's site I). The influence of interference of some common metal ions on the binding of PAH to HSA was studied. Synchronous fluorescence spectra(SFS), 3D fluorescence spectra and circular dichroism(CD) results indicated the conformational changes in the structure of HSA.
文摘Turbidimetry and radioimmunoassay were used to study the effects of procainamide (PA ) onadenosine diphosphate (ADP)-induced rabbit platelet aggregation and thromboxane B2 (TXB2) production invitro. PA 8. 5--544. 0 μmol L-1 inhibited ADP-induced platelet aggregation and TXB2 production, and theinhibition rates were 26. 7% -- 66. 7 % and 21. 4 % -- 70. 1 %, respectively. There was positive correlation between PA concentration and its efficiency in inhibiting the platelet aggregation and TXB2 production, and alsobetween the inhibition rates of platelet aggregation and that of TXB2 production. The three linear equationsand main parameters were The results indicate that PA could significantly inhibit ADP--induced platelet aggregation and TXB2 production in rabbits.
文摘Objective:To test the effect of voltage-gated sodium channels (VGSCs) blockers on the motility and viability of human spermin-vitro and to evaluate the tested compounds as potential contact spermicidal.Methods: Sperm samples were obtained from healthy non-smoking volunteers of age 25-30 years who had not taken any drug 3 months before and during the course of the study. The effect of VGSCs blockers evaluated from two pharmacological classes including antiarrhythmic (amiodarone, procainamide and disopyramide) and antiepileptic (carbamazepine, oxcarbazepine, phenytoin, and lamotrigine) drugs. They were tested on thein-vitro motility and viability of human sperm using Computer Assisted Semen Analyzer.Results:All tested drugs except oxcarbazepine showed dose dependent inhibition of total motility with significant reduction (P<0.05) at the maximum concentration of 200 μM when compared with the control. The concentrations of drugs that reduced total sperm motility to 50% of control (half maximal inhibitory concentration) were 2.76, 14.16 and 20.29 μM for phenytoin, lamotrigine and carbamazepine, respectively;and 2.53, 5.32 and 0.37 μM for amiodarone, procainamide and disopyramide, respectively. The anti-motility effects were reversible to various degrees. There was statistically insignificant difference in the inhibition of sperm viability among amiodarone, procainamide and disopyramide. Phenytoin demonstrated the most potent spermicidal action.Conclusions:VGSCs blockers have significant adverse effects onin-vitro motility of human spermatozoa. Soin-vivo studies are required to determine their potential toxicological effects on human semen quality, which is an important factor regarding fertility. Moreover, these drugs have the potential to be developed into contact spermicidal.