雷帕鸣效果怎样？

It is a lipophilic nitrogen-containing 36$ macrolide antibiotic naturally produced from Streptomyees hygroscopicus. Its molecular formula is C51H79NO13 and its molecular weight is 914.17. Rapamin is a white crystal with a melting point of 183~184°C and an optical rotation of -147°~-157° (c=l.02, chloroform). Soluble in methanol, ethanol, acetone, ethyl acetate, chloroform or ether, insoluble in hexane or petroleum ether, insoluble in water. 

Rapamin and FK506 are structural homologs. Although they act on the same receptor, their immune action mechanisms are different. FK506 inhibits the proliferation of T lymphocytes from the G0 phase to the G1 phase, while rapamycin blocks signaling through different cytokine receptors, blocking the progression of T lymphocytes and other cells from the GI phase to the S phase. Compared with FK506, rapamycin blocks the calcium-dependent and calcium-independent signaling pathways P1 of T lymphocytes and B lymphocytes. Current research shows that FK506 and cyclosporine A produce immunosuppressive effects by inhibiting calcineurin, while rapamycin inhibits the body's immune function by affecting unique cell signaling pathways. Rapamin and FK506 share the same receptor in the body, namely FK506 immune binding protein (FKBP). After rapamin binds to FKBP, on the one hand, it inhibits the activation of 70-KSU6 kinase (p7), preventing the ribosome 40S subunit S6 protein from phosphorylating g7, affecting protein synthesis; on the other hand, it inhibits cyclin D2, D3 and cell cycle-dependent kinase, cdk4. The expression of cdk6 and the activation of Cyclin E-cdk2 complex cause cells to arrest in the middle and late stages of GI and cannot continue to proliferate. Its direct target may be a protein mammalian'rOR (mTOR) that has a homologous sequence to phospholipid phthaloinositide kinase. That is, the product of the combination of the FKBP complex and mTOR can block the immune response triggered by the activation of mTOR by H, -2, U, -15 or CD28/B7 costimulatory pathways, thus exerting a powerful immunosuppressive effect.