摘要
目的 :研究AnnexinA7在早期胚胎发育过程中对钙平衡调节的作用 .方法 :利用钙成像技术和膜片钳技术检测敲除AnnexinA7小鼠的早期胚胎心肌细胞的钙平衡以及相应的离子通道的特性 .结果 :在胚胎心肌细胞发育的早期 ,敲除AnnexinA7小鼠胚胎心肌细胞的静息钙 (340 / 380荧光比例 0 .78± 0 .0 2 )、钙峰值 (340 / 380荧光比例 1.2 8± 0 .0 5 )和正常细胞的值相似 ;动作电位 (APD90 2 4 2 .7± 4 3.7ms、最大去极化电位 5 6 .8± 1.7mV)以及L 型钙电流密度 (14 .1± 2 .5pA/ pF)和正常细胞的相似 ,并且钙电流能被碳酰胆碱减小(5 1.7± 8) % ,也和正常细胞相似 .结论 :敲除AnnexinA7基因的小鼠早期胚胎心肌细胞具有正常的钙稳态以及正常的离子通道 .
AIM: To study the involvement of Annexin A7 in the regulation of Ca 2+ homeostasis in embryonic development stage. METHODS: Single cell Ca 2+ imaging techniques and patch clamp technique were used to test the current of ion channel and action potential of Annexin A7 knock out mice embryonic heart cells. RESULTS: During early embryonic development (E11.5/E12.5) resting Ca 2+ (ratio 0.78±0.02), values of peak Ca 2+ concentration (ratio 1.28±0.05, n =30) were quite same to control cells. Anxa 7 -/- cardiomyocytes displayed normal action potentials (APD90 242.7±43.7 ms, a maximum diastolic potential of 56.8±1.7 mV) , and the density of L type Ca 2+ currents in Anxa 7 -/- cardiomyocytes (14.1±2.5 pA/pF) were quite same to control cells. Especially basal I Ca was depressed by CCh (1 μmol·L -1 ) by (51.7±8)%. CONCLUSION: Early embryonic cardiomyocytes of Anxa 7 -/- mice display intact Ca 2+ homeostasis and express all the components required for excitation contraction coupling.
出处
《第四军医大学学报》
北大核心
2003年第3期193-195,共3页
Journal of the Fourth Military Medical University
