地肤子70%醇提物抑制速发型及迟发型变态反应

目的：研究地肤子70％醇提物对速发型变态反应及迟发型变态反应（DTH）早期相和后期相的抑制作用，探讨其可能的作用机制。方法：体外试验中，分别将地肤子醇提物与大鼠腹腔肥大细胞或离体豚鼠回肠预温孵，观察其对compound 48/80诱导肥大细胞释放组胺（荧光法）及5－HT诱导豚鼠回肠收缩的影响，在SRBC和PC诱发的小鼠DTH模型，将地肤子醇提物及其总皂苷于抗原攻击后给药，观察其对DTH效应早期和后期反应的作用。结果：地肤子醇提物浓度依赖性抑制大鼠腹腔肥大细胞释放组胺，对5－HT所致豚鼠回肠收缩亦具有一定的抑制作用；地肤子醇提物及其总皂苷均能抑制TH效应相的早期和后期反应，且对早期反应的作用强于对后期反应。结论：地肤子可能主要通过稳定肥大细胞膜，减少组胺，5－HT等过敏介质的释放抑制速 发型变态反应及DTH效应相的早期反应，其对DTH后期反应的抑制作用则可能与抗炎作用有关，地肤子皂苷为其抑制DTH的有效成分。

Inhibition of lmmediate and delayed type hypersensitivity by the 70% ethanolic extract from Fructus Kochiae Scopariae

OBJECTIVE:To study the inhibitory activities of the 70% ethanolic extract from Fructus Kochiae Scopariae(FKS) on the immediate and the early and late phases of delayed type hypersensitivity(DTH),and explore its mechanisms of action.METHOD:In vitro,FKS was pre incubated with rat peritoneal mast cells and isolated guinea pig ileum,respectivvly.Its effects on histamine release elicited by compound 48/80 and ileum constriction by 5 HT were observed.In mouse DTH models upon challenge with SRBC or PC,the effects of FKS and total saponin isolated from it on the early and late phases were studied by oral administration after antigen challege.RESULTS:FKS produced a concentration dependent reduction of histamine release from rat peritoneal mast cells and showed an inhibitory tendency on the guinea pig ileum constriction.Furthermore,FKS and its saponin significantly suppressed the two phases of DTH in mice,which were stronger on the early phase than on the late one.CONCLUSION:These findings indicated that FKS inhibited immediate hypersensitivity and the early phase of DTH mainly due to its stabilization of mast cell membrane and reduction of release of histamine,5 HT and other anaphylactic mediators,and inhibited the late phase of DTH maybe due to its anti inflammatory activity.Saponin was the active component of FKS responsible for its inhibition on DTH.