| Objective Since the purpose of the Brain Blood Barrier,BBB the role of the most difficult molecules and water-soluble drug brain delivery.In this paper,the basic nanoparticle carrier neurotoxin targeted drugs,polysorbate 80 is a surface modifications,in the laboratory on the basis of preliminary studies,preparation of P-80 modified neurotoxin nanoparticles and study the physical and chemical properties,and their pharmacodynamic study systematically investigated the drug delivery system is feasible and effective.Wester-blot and immunohistochemical study P-80-neurotoxin nanoparticles nasal administration into the brain changes in the content of P-glycoprotein(P-glyCoprotein,P-gp)brain process,so as to explore in P-gp nano formulation into the role and significance of the brain.Provide experimental basis and technical reference for elucidating protein peptide nano-delivery systems nasal absorption into the brain mechanisms,the development of brain proteins and peptides targeting agents to provide experimental and theoretical basis.Methods 1.In the basic method for nanoparticle carrier neurotoxin target drugs,polysorbate 80 is a surface modification was observed morphology was prepared by emulsion polymerization P-80-neurotoxin nanoparticles,TEM,Zeta potential instrument nanoparticles Zeta potential measurement,laser particle size analyzer to determine the average particle size,ultrafiltration and fluorescence spectrophotometer encapsulation efficiency and drug loading;2.The hot plate test and writhing study P-80-neurotoxin nanoparticles of different routes of administration in mice and the analgesic effect of differences in the characteristics of nanoparticles and investigate neurotoxin modified P-80 before and after the analgesic effect Impact;3.Using Wester-blot detection of P-80-neurotoxin nanoparticles for nasal administration into the brain to exert influence on the efficacy of the process of P-gp expression in the brain;4.immunohistochemical techniques for nasal administration of rat brain changes in micro-capillary endothelial P-gp content were studied using rat brain sections HE staining of the BBB was observed under investigation together with a barrier of P-gp after neurotoxin modified P-80 before and after the nanoparticles play a pharmacodynamics process changes.Results 1.P-80-NT-NP look good shape,an average particle diameter(78.27±2.09)nm,Zeta potential(-15.38±1.22)mV,the encapsulation efficiency was(75.61±2.59)%,drug loading It is(0.186±0.05)%.2.mouse hot plate analgesia test display,after a modified P-80 NT-NP intranasal unmodified NT-NP between 30-180min significant difference(P<0.05),which 90-120min show significant differences(P<0.01).P-80-NT-NP nasal administration,intramuscular injection,intraperitoneal injection,respectively 120min,150min,180min and reached the peak,P-80-NT-NP in 30-150min pain threshold increase rate has greatly improved;and physiology compared to saline group,P-80-NT-NP intranasal administration showed significant differences(P<0.05)in 30-210min,which 60-180min there was a significant difference(P<0.01);and P-80-NT-NP intraperitoneal injection group reached the pain threshold of the peak(49.46%)at 180min when compared with Ns intraperitoneal injection group,there are differences in 120-180min time.Writhing analgesic experiments show that after the NT made nanoparticles,writhing latencies increase,within 15min twist significantly reduced the number of bodies,nasal administration group compared with NT,NT-NP in.Showed a significant difference sex(P<0.05),P-80-NT-NP there was a significant difference(P<0.01),P-80-NT-NP by intraperitoneal injection,writhing incubation period is longer,reducing the inner 15min writhing;P-80-NT-NP after intramuscular administration writhing significantly reduced,compared with the Ns group,there was a significant difference(P<0.05);P-80-NT-NP mice after intranasal administration of twisting a significant reduction in the number of the body,compared with Ns group,the difference was significant(P<0.01).3.Western blot test results showed that,compared with the saline group,NT was no significant difference,NT-NP group showed significant differences(P<0.05),P-80-NT-NP intranasal and intravenous injection appears highly significant difference(P<0.01);compared with NT-NP group P-80-NT-NP intranasal administration and administered by intravenous injection appeared significant difference(P<0.05);and P-80-NT compared to a tail vein injection-NP intranasal administration group a significant difference(P<0.05).4.The results of immunohistochemical staining showed that,compared with the NT group,the positive cells NT-NP group 60min when P-gp expression after intranasal administration,IOD reach the low peak,30min-120min between NT-NP group P positive cells-gp expression,IOD both appear to inhibit(P<0.05);P-80-NT-NP group 120min when positive after intranasal administration of P-gp cells,IOD peak,30min when P-gp emergence inhibition(P<0.05),60min-120min between positive cells of P-gp,IOD is highly significant statistically significant difference(P<0.01),at 180min when P-gp inhibition are still differences(P<0.05).Compared with NT-NP group,the positive cells after nasal administration of P-gp,IOD expression appears P-80-NT-NP group in 60min-180min difference between(P<0.05),which 120min when P-the number of positive cells gp,IOD expression appears highly significant difference(P<0.01).Conclusion The preparation of P-80-neurotoxin nanoparticles by physical and chemical properties,the pharmacodynamic study of nasal mucosa after administration successfully constructed P-80-neurotoxin nanoparticle drug delivery system in the brain;Western Bloting and immunohistochemistry studies P-glycoprotein P-80-neurotoxin nanoparticles after administration into the nasal cavity of rats through the mechanism of the brain,P-gp transporter in neurotoxic nanoparticles for nasal administration into the brain of Chinese and foreign efflux pump It is inhibited by the preparation of nanoparticles,and by P-80 modified neurotoxin nanoparticles inhibit the more obvious. |
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