Inhibitory effects of insulin on cytosolic Ca2+ level and contraction in the rat aorta. Endothelium-dependent and -independent mechanisms.
Inhibitory effects of insulin on cytosolic Ca2+ level and contraction in the rat aorta. Endothelium-dependent and -independent mechanisms.
复制标题
胰岛素对大鼠主动脉胞质 Ca2 水平和收缩的抑制作用。
作者：
Shu;Yasuyoshi Ouchi;H. Karaki;H. Orimo
为探讨胰岛素对血管张力抑制作用的机制，在离体大鼠主动脉中同时测量收缩和内皮细胞及平滑肌细胞内Ca 2+水平（[Ca 2 +]i）。胰岛素（200 mU/mL）增加内皮细胞[Ca 2 +]i，降低静息肌张力。内皮细胞的去除取消了胰岛素的作用。在去甲肾上腺素预收缩的主动脉中，胰岛素（3至120 mU/mL）诱导浓度依赖性收缩抑制。舒张作用表现为内皮细胞[Ca ~（2+）]i升高，平滑肌[Ca ~（2+）]i降低。去内皮或加入10（-5）mol/L NG-单甲基-L-精氨酸可减弱其舒张作用，而10（-5）mol/L吲哚美辛则无此作用。在无内皮细胞的情况下，胰岛素的舒张作用伴随着平滑肌[Ca 2 +]i的降低。结果提示，胰岛素通过双重机制抑制大鼠主动脉收缩：（1）胰岛素通过增加内皮细胞[Ca ~（2+）]i和释放NO作用于血管内皮，降低平滑肌[Ca ~（2+）]i和收缩元件的Ca ~（2+）敏感性; (2)胰岛素还直接作用于平滑肌，降低平滑肌[Ca 2 +]i。
To determine the mechanism of the inhibitory effect of insulin on vascular tone, contraction was measured simultaneously with endothelial and smooth muscle cytosolic Ca2+ level ([Ca2+]i) in the isolated rat aorta. Insulin (200 mU/mL) increased endothelial [Ca2+]i and decreased resting muscle tone. The removal of endothelium abolished the effects of insulin. In the aorta precontracted with norepinephrine, insulin (3 to 120 mU/mL) induced concentration-dependent inhibition of contraction. The relaxant effect followed the increase in endothelial [Ca2+]i and decrease in smooth muscle [Ca2+]i. The relaxant effect was attenuated by removal of endothelium or by the addition of 10(-5) mol/L NG-monomethyl-L-arginine but not by 10(-5) mol/L indomethacin. In the absence of endothelium, the relaxant effect of insulin followed the decrease in smooth muscle [Ca2+]i. These results suggest that insulin inhibits vascular contraction by dual mechanisms in the isolated rat aorta: (1) Insulin acts on vascular endothelium by increasing endothelial [Ca2+]i and releasing NO, which decreases smooth muscle [Ca2+]i and the Ca2+ sensitivity of the contractile elements. (2) Insulin also directly acts on smooth muscle and decreases smooth muscle [Ca2+]i.
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钙在动脉平滑肌内皮依赖性松弛中的作用。
DOI：
10.1016/0002-9149(87)90174-3
发表时间：
1987
期刊：
The American journal of cardiology
影响因子：
--
作者：
Peach,MJ;Singer,HA;IzzoJr,NJ;Loeb,AL
通讯作者：
Loeb,AL
影响因子：
15.9
作者：
ANDERSON, EA;HOFFMAN, RP;MARK, AL
通讯作者：
MARK, AL
胰岛素可减弱大鼠血管平滑肌细胞中加压素诱导的钙瞬变和电压依赖性钙反应。
DOI：
10.1172/jci115426
发表时间：
1991
期刊：
The Journal of clinical investigation
影响因子：
--
作者：
Standley,PR;Zhang,F;Ram,JL;Zemel,MB;Sowers,JR
通讯作者：
Sowers,JR
影响因子：
15.9
作者：
LAAKSO, M;EDELMAN, SV;BARON, AD
通讯作者：
BARON, AD