摘要
目的研究褪黑素(melatonin)对长期接受己烯雌酚(DES)大鼠垂体非组织特异性calpains表达及活性变化的影响。方法30只♀Wistar大鼠,实验分5组:组1:腹腔注射葵花油(1ml.kg-1,每周两次)共计16wk;组2:腹腔注射己烯雌酚(DES,5mg.kg-1,每周两次),共计16wk;组3:腹腔注射DES(5mg.kg-1,每周两次),连续12wk,之后停止给予DES至第16周结束;组4和组5:腹腔注射己烯雌酚溶液(1mg·kg-1,每周两次),连续16wk,并于实验第13周开始分别同时给予皮下注射褪黑素(0.25mg.d-1和1.0mg.d-1),至第16周结束。使用蛋白质印迹(Westernblot)法检测垂体组织μ-和m-calpains表达,采用酪蛋白酶谱法观察不同组别垂体组织胞质及膜成分中μ-和m-calpains的活性变化。结果长期给予DES垂体组织μ-和m-calpain水平升高,膜成分活性增高,而停止给予DES或同时应用不同剂量褪黑素可不同程度降低μ-和m-calpain水平,抑制两种非组织特异性calpains的激活。结论长期给予♀性Wistar大鼠DES可使垂体组织中calpains表达及激活明显增高,并具有一定的雌激素依赖性。不同剂量的褪黑素可减少cal-pains表达,稳定胞质中calpains,抑制其转膜激活。
Aim To investigate the effect of melatonin on μ-and m-calpains expression and their Ca2＋-dependent activities in diethylstilbestrol（DES）-treated female Wistar rats.Methods 30 female Wistar rats were randomly allocated into 5 groups.In group 1,rats received intraperitoneal injection of sun flower seed oil for 16 weeks.In group 2,rats were intraperitoneally administered with DES（5 mg· kg^-1,twice a week）for 16 weeks,whereas rats in group 3 was administered with DES（5 mg· kg^-1,twice a week）for 12 weeks,followed by its discontinuation for 4 weeks.In group 4 and 5,rats received DES（5 mg· kg^-1,twice a week）for 16 weeks,with subcutaneous co-administration of melatonin at doses of 0.25 mg·d^-1 and 1.0 mg·d^-1 respectively at the beginning of week 13.Pituitary tissues were harvested for expression of two ubiquitous calpains through Western blot and their cytosol and membrane activities through casein zymography.Results Long-term treatment of DES up-regulated expression of two ubiquitous calpains and their in vitro activities.DES discontinuation or melatonin administration at 2 doses significantly reduced their expression and in vitro activities.Conclusions Expression and activities of both μ-and m-calpains are up-regulated in response to long term treatment of DES,which is DES dependent and can be down-regulated by melatonin.The results present ubiquitous calpains the treatment targets for melatonin.
出处
《中国药理学通报》
CAS
CSCD
北大核心
2010年第5期624-628,共5页
Chinese Pharmacological Bulletin
