THE SYMPATHETIC RESPONSE TO EUGLYCEMIC HYPERINSULINEMIA - EVIDENCE FROM MICROELECTRODE NERVE RECORDINGS IN HEALTHY-SUBJECTS
THE SYMPATHETIC RESPONSE TO EUGLYCEMIC HYPERINSULINEMIA - EVIDENCE FROM MICROELECTRODE NERVE RECORDINGS IN HEALTHY-SUBJECTS
复制标题
DOI：
10.1007/bf00399935
复制
发表时间：
1992-09-01
期刊：
影响因子：
8.2
通讯作者：
HJEMDAHL, P
中科院分区：
文献类型：
--
作者：
BERNE, C;FAGIUS, J;HJEMDAHL, P
由胰岛素激活的交感神经系统被认为是解释胰岛素抵抗和高血压之间联系的一种机制。我们进一步通过直接显微神经学肌肉和皮肤神经交感神经活动记录，在健康受试者的正常血糖胰岛素钳夹期间检测了胰岛素的影响。7名受试者在90min的一步钳夹中，平均血浆胰岛素水平从5.3+/-0.7升至92.2+/-2.2 mU/L。另6例受试者血浆胰岛素在45~90min(两步钳夹)由85.7+/-4.0mU/L进一步升高至747+/-53mU/L。后四名受试者只在第二次记录过程中接受了含有氯化钠的假钳子。在小剂量胰岛素作用下，肌肉神经的交感神经活动从安静时的22.7+/-5.0次/min增加到15分钟时的27.7+/-5.0次/min(p<；0.05)。在整个胰岛素输注过程中，肌神经交感神经活动显著增加(p<；0.001；ANOVA)，在超生理胰岛素浓度时略有增加(从每分钟29.2+/-1.6次增加到32.3次/-1.9次/分钟)。假夹闭期间，肌神经交感神经活动未见增加。两种胰岛素钳夹均可引起前臂静脉血浆去甲肾上腺素浓度轻微但显著升高。皮神经交感神经活动(n=3)在胰岛素输注过程中无明显变化。在胰岛素夹期间，心率略有增加，但显著增加(p<；0.005)。血压没有受到明显影响。总之，高胰岛素血症与骨骼肌血管收缩神经活动增加有关，而交感神经向皮肤流出的变化不明显。
Sympathetic nervous system activation by insulin has been suggested as a mechanism explaining the association between insulin resistance and hypertension. We further examined the effect, of insulin by direct microneurographic muscle and skin nerve sympathetic activity recordings during euglycaemic insulin clamps in healthy subjects. The mean plasma insulin level was elevated from 5.3 +/- 0.7 to 92.2 +/- 2.2 mU/l in seven subjects during a 90-min one-step clamp. In six other subjects plasma insulin was further raised from 85.7 +/- 4.0 mU/l to 747 +/- 53 mU/l between 45-90 min (two-step clamp). Four of the latter subjects received a sham clamp with NaCl infusions only on a second recording session. At the low dose of insulin muscle nerve sympathetic activity increased from a resting level of 22.7 +/- 5.0 bursts per min to 27.7 +/- 5.0 bursts per min at 15 min (p < 0.05). The increases in muscle nerve sympathetic activity were significant (p < 0.001; ANOVA) throughout insulin infusion, with a slight further increase (from 29.2 +/- 1.6 to 32.3 +/- 1.9 bursts per min) at the supraphysiological insulin concentration. During sham clamps muscle nerve sympathetic activity did not increase. Both insulin clamps induced minor, but significant, increases in forearm venous plasma noradrenaline concentrations. Skin nerve sympathetic activity (n = 3) did not change during insulin infusions. Heart rate increased slightly but significantly (p < 0.005), during the insulin clamps. Blood pressure was not notably affected. In conclusion, hyperinsulinaemia was associated with increased vasoconstrictor nerve activity to skeletal muscle and with no change of sympathetic outflow to skin.