ABSTRACT
OBJECTIVE:To prepare lung-targeting hydroxycampothecinum(HCPT) microspheres and evaluate its in vitro release characteristics and its lung-targeting property in mice.METHODS:The microspheres was prepared by solvent volatilization with polylactic acid as chief excipient.The particle size,entrapment efficiency(EE) and drug loading(DL) of the microspheres were studied and the in vitro release rate was compared with that of the crude drug.12 mice enrolled were injected via vena caudalis with HCPT micropheres or HCPT crude drug,at 30 min,the drug level in plasma and tissues were determined and the relative distribution rates(RDR) were computed.RESULTS:81.6% of the microspheres ranged from 7～ 30 ?m in particle size,the mean diameter was (14.2?3.1) ?m,the EE was 72.36%,the DL was (40.6?3.6)%,and the in vitro drug release parameter T50 was 85 min for microspheres vs.18 min for crude drug.The drug level of the microspheres in lung was the highest at (32.2?2.48) ?g?mL-1 with a RDR of 58.1%;The drug level of the crude drug group in plasma was the highest at (13.52?2.58) ?g?mL-1 with a RDR of 25.24%.CONCLUSION:The prepared HCPT microspheres had the distinctive characteristics of sustained-release and lung targeting.
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OBJECTIVE:To study the scavenging action of Longyanshen on O2 ?- and ? OH.METHODS:Spectrophotometry (wavelength 322nm and 536nm)was used to detect the effects of Longyanshen upon O2 ?- and?OHRESULTS:Longyanshen in concentration of 30g/ml could reduce the level of?OH by 284%,and Longyanshen in concentrations of 15g/ml,30g/ml and 60g/ml could decrease the levels of O2 ?- by 441%,630% and 479% and inhibit the generation of O2 ?- by 489%,589%and 675% in vitro,respectivelyCONCLUSION:The results show that Longyanshen could scavenge and inhibit O2 ?- markedly(P
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OBJECTIVE:To study the protective effects and mechanisms of Longyanshen on chemical liver injury in mice.METHODS:The models of CCl 4 ,TAA and acetaminophen induced acute liver injury in mice were used to study the pro?tective effects of Longyanshen,and relevant parameters were detected and compared.RESULTS:Compared with model group,in Longyanshen group,activity of ALT markedly decreased,the contents of hepatic cyt P 450 ,cyt b 5 increased,the content of MDA in liver tissue significantly decreased,the activities of aniline hydroxylase and aminopurine-N-demethylase increased,the activity of Ca 2+ -ATPase in hepatic cell microsome markedly decreased and the activities of GSH-PX and the content of GSH increased.CONCLUSION:Longyanshen has protective effect on chemical liver injury in mice and the mechanisms may be related to the antioxidative action,inhibiting effect on lipid peroxidation,inducing the activities of hepatic microsomal enzymes and blocking the calcium channel.
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OBJECTIVE:To observe the effect of extract of longyanshen(EL)on immunodepression induced by cyclophosphamide in mice.METHODS:The immunodepression was induced by cyclophosphamide,the the different oral doses of EL were given to mice for 30 days,and control group took NS.RESULTS:The different doses of EL could significantly increase the killing function of neutrophil(P