组蛋白乙酰化酶p300和CREB结合蛋白在小鼠胚胎心发育中的时序表达

目的:探讨p300和CREB结合蛋白(CBP)在小鼠胚胎心发育过程中的时序表达规律.方法:选取胎龄7.5～18 d、出生1 d、3月小鼠正常心,采用免疫组织化学法观察p300和CBP在小鼠胎心发育中的表达分布及变化规律.结果:p300在胚胎心发育各个时期及出生1 d和3月成年鼠的心各部分均有很强表达.CBP在E7.5不表达;在E8.5～E9.5的心管中较强表达;E10.5～E16.5及E18和生后1 d心肌较强表达,房室瓣和小梁网较弱表达,室间隔肌部弱表达而膜部几乎不表达;3月成年鼠心肌和小梁较弱表达,室间隔极弱表达.结论:p300对发育早期的生心细胞诱导特化和中期的室间隔形成作用较CBP更大.

Spatiotemporal expressions of histone acetyltransferases p300 and CREB binding protein during mouse embryonic heart development

Objective: To investigate the spatiotemporal expressions of p300 and CREB binding protein(CBP) in the heart development of embryonic mouse.Methods: 39 samples from normal mouse fetal hearts at embryonic days 7.5-18 and postnatal 1 day and 3 months were included in this study.Immunohistochemiscal analysis was used to detect the distributions and expression changes during mouse cardiac morphogenesis.Results: p300 strongly expressed in every parts of heart during different stages of embryonic heart development and postnatal 1 day and 3 months.No CBP expression was detected at E7.5.CBP relatively strongly expressed at the cardiac tube at E8.5 and E9.5.At E10.5-E18 and postnatal 1 day,CBP was found relatively strongly positive in myocardium and weakly positive in atrioventricular valves as well as trabeculae and very weakly positive in muscular interventricular septum and hardly positive in membranous interventricular septum.CBP was relatively weakly positive in myocardium as well as trabeculae and very weakly in interventricular septum in the 3-month old mouse.Conclusion: p300 may play a greater role in cardiac precursor cells induction and specification and interventricular septum formation than CBP do.