摘要
目的 了解酪氨酸蛋白激酶信号途径在不同α1肾上腺素受体亚型Ca2 +调控中的作用。方法 用Fura 2荧光探针双波长测定细胞胞浆游Ca2 +浓度 ([Ca2 +]i)的方法 ,在分别转染了α1A、α1B和α1D肾上腺素受体cDNA的HEK2 93细胞 ,观察酪氨酸蛋白激酶抑制剂Genistein和磷脂酶C抑制剂U7312 2 对激动不同α1肾上腺素受体亚型引起的 [Ca2 +]i 变化的影响。结果 预先用U7312 2 (0 1,10 ,5 0 μmol·L-1)与细胞共同孵育 10min ;用Genistein(10 ,10 0 ,2 0 0 μmol·L-1)与细胞共同孵育 1h。在分别转染了α1A、α1B和α1DcDNA的HEK2 93细胞 ,U73 12 2 和Genistein均能浓度依赖性地抑制肾上腺 (10 μmol·L-1)引起的双相 [Ca2 +]i 的升高。在上述细胞 ,U7312 2 (5 0 μmol·L-1)能完全抑制肾上腺素引起的[Ca2 +]i 升高 ;而用最大有效浓度 10 0 μmol·L-1的Genistein只能部分抑制肾上腺素升高 [Ca2 +]i 的作用。结论 在HEK 2 93细胞 ,不同α1肾上腺素受体亚型 (α1A α1B和α1D)激动均能部分通过酪氨酸蛋白激酶信号途径引起Ca2 +释放和Ca2 +内流。
AIM To understand whether the tyrosine protein kinase(TPK) pathway is involved in the Ca 2+ movement evoked by activation of α 1 adrenoceptor subtypes. METHODS The intracellular Ca 2+ concentration([Ca 2+ ] i) was measured with Fura 2 probe in transfected HEK293 cells with α 1A , α 1B and α 1D adrenoceptor cDNA. The effects of genistein, a TPK inhibitor and U 73122 , a phospholipase C(PLC) inhibitor on the response of [Ca 2+ ] i to activation of different α 1 adrenoceptor subtypes by adrenaline(Adr, 10 μmol·L -1 ) were investigated respectively. RESULTS Pre incubated the cells with U 73122 or genis tein, the biphasic increase in [Ca 2+ ] i induced by Adr were inhibited by U 73122 (0 1, 1, 10, 50 μmol·L -1 ) and genistein ( 10, 100, 200 μmol·L -1 ) in a concentration dependent manner in all transfected HEK293 cells. The [Ca 2+ ] i response to Adr was fully blocked by U 73122 (50 μmol·L -1 ) but partly inhibited by maximal effective concentration of genistein(100 μmol·L -1 ). CONCLUSION Activation of different subtypes of α 1 adrenoceptor induces Ca 2+ release and Ca 2+ influx through stimulation of TPK protein in HEK293 cells. Both G protein pathway and TPK pathway may be involved in the activation of PLC by α 1 adrenoceptor stimulation.
出处
《中国药理学通报》
CAS
CSCD
北大核心
2000年第4期387-391,共5页
Chinese Pharmacological Bulletin
基金
国家自然科学基金资助课题 !No 39870 881
