摘要
目的:研究粉防己碱对心肌的作用。方法:采用Fura-2和AR-CM-MIC阳离子测定系统测定培养大鼠单个心肌细胞胞内游离钙。结果:外钙1.3mmol·L^(-1)时,细胞静息钙为90±12nmol·L^(-1)。粉防己碱不影响静息钙,但可明显抑制CaCl_2,KCl,哇巴因引起的胞内钙增高;对于去甲肾上腺素引起的胞内钙增高,粉防己碱只有在外钙存在时,方对其有抑制作用。结论;粉防己碱抑制钙离子的跨膜运动,但在心肌细胞,它并非是选择性的钙通道阻滞剂。
AIM: To study the effects of tetrandrine (Tet) on myocardium. METHODS: Using Fura 2-AM and AR-CM-MIC cation measurement system, cytosolic free calcium ([Ca2+]i) was examined in cultured rat single myocardial cells. RESULTS; The resting [Ca2+] was 90+12 nmol·L-1 in the presence of Ca2+ 1. 3 mmol ·L-1 in Hanks' solution. Tet 1 -100 μmol·L-1 had no effect on the resting [Ca2+]i, but 10-100 μmol·L-1 depressed the [Ca2+]i elevation when extracellular Ca2+ was 5 mmol · L-1. Tet 1 - 100 μmol · L-1 inhibited KC1 (30 and 60 mmol·L-1) induced [Ca2+]i elevation in a concentration-dependent manner, the IC50 value was 8.8 μmol·L-1(95 % confidence limits; 3. 3-23. 7 μmol·L-1) and 6. 9 μmol·L-1 (95 % confidence limits; 2.8-17.4 μmol·L-1), respectvely. Norepinephrine (NE) 10 μmol·L-1 caused a rapid increase in [Ca2+]i in the presence or abscence of extracellular Ca2+, Tet 30- 100 μmol·L-1 only decreased the former. Tet 10 -100 μmol·L-1 also decreased ouabain (Oua)-in-duced elevation in [Ca2+]. CONCLUSION: Tet had inhibitory effects on Ca2+ transmembrane movement, but it is not a selective calcium channel blocker in rat myocardial cells.
出处
《中国药理学报》
CSCD
1996年第1期55-58,共4页
Acta Pharmacologica Sinica
关键词
粉防己碱
心肌
钙
钙通道阻
滞剂
大鼠
tetrandrine
myocardium
Fura- 2
calcium
calcium channel blockers
berbines
cultured cells