Tacrolimus (FK506) 是一种23元大环内酯物，通过结合到抑免蛋白 FKBP12 (FK506结合蛋白) 产生新的复合物，从而降低T细胞中肽酰脯氨酰异构酶活性。

FK-506和环孢霉素A阻断细胞质成分的移位，而不影响T淋巴细胞中核亚基的合成。FK-506通过抑制需要白细胞介素-2转录诱导的Ca(2+)-依赖过程，阻止T细胞增殖。FK-506结合于不同的细胞内蛋白质(免疫亲和素)家族，学术上称为亲环素类和FK 506结合蛋白(FKBPs)。FK-506特异性抑制细胞内磷酸酶，在药物浓度下，抑制活化的T细胞中白介素2的产生。FK-506和CsA通过抑制早期钙相关的涉及淋巴因子表达，凋亡，和脱粒作用，在细胞中几乎发挥相同的生物学作用。FK-506与细胞内受体家族结合，学术上称为FK-506结合蛋白(FKBPs)。

>98 %

Store at -20℃ for one year（Powder）；Store at 2-4℃ for two weeks；Store at -20℃ for six months after dissolution.

他克莫司; Tacrolimus；FK506；FK 506；Fujimycin；FR900506

white solid

DMSO：94 mg/mL (116.91 mM)

Ethanol：83 mg/mL (103.23 mM)

FKBP12

FK-506 and cyclosporin A block translocation of the cytoplasmic component without affecting synthesis of the nuclear subunit in T lymphocytes. FK-506 prevents T-cell proliferation by inhibiting a Ca(2+)-dependent event required for induction of interleukin-2 transcription. FK 506 binds to distinct families of intracellular proteins (immunophilins) termed cyclophilins and FK 506-binding proteins (FKBPs). FK-506 specifically inhibits cellular calcineurin at drug concentrations that inhibit interleukin 2 production in activated T cells. FK-506 and CsA exert nearly identical biological effects in cells by inhibiting the same subset of early calcium-associated events involved in lymphokine expression, apoptosis, and degranulation. FK-506 binds to a family of intracellular receptors termed the FK-506 binding proteins (FKBPs).

FK-506 results in increase in the paw and tail withdrawal threshold as revealed by behavioral pain assessment in rats against hyperalgesic and allodynic stimuli. FK-506 also leads to a decrease in the serum nitrate and thiobarbituric acid reactive substance (TBARS) levels along with reduction in tissue myeloperoxidase (MPO) and total calcium levels, whereas, rise in tissue reduced glutathione levels in rats. FK-506 ameliorates the increase in the neuronal edema and axonal degeneration in rats with ischemia reperfusion (I/R).