肝细胞色素P450 3A在衰老加速鼠中的作用

Effect of aging on the activity of CYP3A in the senescence accelerated mouse (SAM) livers

为探讨衰老与细胞色素P4503A（CYP3A）的活性是否有关，本文用红霉素N-脱甲基酶活性测定法分别检测了SAM-R1、SAM-P1和SAM-P8三组衰老加速鼠（SAM）中肝微粒体细胞色素P4503A的活性，每组动物分为7、13、36周龄组。结果发现SAM－P1和SAM－P8组中随年龄增长，CYP3A的活性均降低。13周时，SAM－P1组CYP3A活性下降39．5％（t＝2．525，P＜0．05）；SAM－P8组CYP3A活性下降约43．7％（t＝2．24，P＜0．05），36周与13周组相比，SAM－P1组CYP3A活性下降约71．3％（t＝2．84，P＜0．02），SAM－P8组中降低约62．9％（t＝3．21，P＜0．01），SAM－R1组中7－13周时降低约13．6％，13周至36周降低约38．2％，t＝2．37．P＜0．05。提示细胞色素P4503A对衰老有重要影响作用。

To determine whether senescence is concemed with CYP3A activity, the activities of the SAM hepatic cy-tochrome P450 3A (CYP3A) were quantified in vitro as erythromycin N-demethytation in microsomes Prepared from SAM-R1、SAM-P1 and SAM-P8, respectively, at 7、 13 and 36 weeks of age in every animal group.We found CWP3A activity was de-creased with advancing age in SAM-P1 and SAM-P8. At 13 weeks of age, CYP3A activity was about 39.5% lower (t = 2.525,P < 0.05) in SAM-P1 and about 43.7% lower (t = 2.24, P < 0.05) in SAM-P8. Compared with 36 to 13 weeks of age thesetwo groups, CYP3A activity was decreased approximately 71 .3% (t = 2.84, P < 0.02) in SAMP-1 and 62.9% (t = 3.2l,P < 0.01) in SAM-P8. It was no significant differences from 7 to 13 weeks of age in SAM-R1, but from 13 to 36 weeks of age,it was decreased about 38. 2% (t = 2. 37. P < O.05) .Taken together, the data suggest that CYP3A takes very importan effectto senescence.