Early gestation dexamethasone alters baroreflex and vascular responses in newborn lambs before hypertension.
Early gestation dexamethasone alters baroreflex and vascular responses in newborn lambs before hypertension.
复制标题
妊娠早期地塞米松在高血压之前改变新生羔羊的压力反射和血管反应。
DOI：
10.1152/ajpregu.00677.2005
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发表时间：
2006
期刊：
影响因子：
--
通讯作者：
Lamb,FredS
中科院分区：
文献类型：
--
作者：
Segar,JeffreyL;Roghair,RobertD;Segar,EmilyM;Bailey,MelissaC;Scholz,ThomasD;Lamb,FredS
妊娠早期羊胎儿暴露于外源性糖皮质激素会引起产后心血管生理学的改变，包括高血压。为了确定在发生全身性高血压之前，自主神经功能和全身血管反应性是否会因子宫内编程而改变，我们检查了暴露于妊娠早期糖皮质激素的 10 至 14 日龄新生羔羊的动脉压力感受反射功能以及体内血流动力学和体外血管对血管活性药物的反应。从妊娠27天（足月145天）开始，对怀孕母羊静脉滴注地塞米松（Dex，0.28 mg·kg−1·day−1）或生理盐水48小时以上，让羔羊分娩（每组n=6）。 Dex 暴露组和对照组动物的静息平均动脉血压（MABP；77 ± 1 与 74 ± 3 mmHg）和心率（HR；249 ± 9 与 226 ± 21 次/分钟）分别相似。在暴露于 Dex 的羔羊中，将 HR 变化与 MABP 联系起来的动脉压力感受反射曲线显着向高压方向移动，尽管反应的敏感性（增益）没有变化。两组中推注剂量 ANG II（20、50 和 100 ng/kg）和去氧肾上腺素（2、5 和 10 μg/kg）引起的体内血压变化相似。然而，Dex 羔羊在用四乙基溴化铵（10 mg/kg；-30 ± 3 与 -20 ± 3 mmHg，P< 0.05）进行神经节阻断后，MABP 出现更大的降低，而在用 NG-硝基-L-精氨酸阻断一氧化氮合酶后，MABP 出现更大的增加（25 mg/kg；23 ± 3 与 13 ± 2 mmHg，P< 0.05) 与对照羔羊相比。通过体外钢丝肌造影，与对照组相比，Dex 羔羊的肠系膜和股动脉微血管对 KCl 的收缩反应相似，而对内皮素（肠系膜）和去甲肾上腺素（股骨）的反应显着减弱。两组对毛喉素和硝普钠的股骨血管舒张反应相似 (n = 4)。这些发现表明，压力反射的重置，伴随着交感神经活动的增加和一氧化氮介导的代偿性血管舒张功能的改变，可能是高血压规划的重要因素。
Exposure of the early gestation ovine fetus to exogenous glucocorticoids induces alterations in postnatal cardiovascular physiology, including hypertension. To determine whether autonomic function and systemic vascular reactivity are altered by in utero programming before the development of systemic hypertension, we examined arterial baroreflex function and in vivo hemodynamic and in vitro vascular responses to vasoactive agents in 10- to 14-day-old newborn lambs exposed to early gestation glucocorticoids. Dexamethasone (Dex, 0.28 mg·kg−1·day−1) or saline was administered to pregnant ewes by intravenous infusion over 48 h beginning at 27 days gestation (term 145 days), and lambs were allowed to deliver (n= 6 in each group). Resting mean arterial blood pressure (MABP; 77 ± 1 vs. 74 ± 3 mmHg) and heart rate (HR; 249 ± 9 vs. 226 ± 21 beats/min) were similar in Dex-exposed and control animals, respectively. The arterial baroreflex curve, relating changes in HR to MABP, was significantly shifted toward higher pressure in the Dex-exposed lambs although no change in the sensitivity (gain) of the response was seen. In vivo changes in blood pressure in response to bolus doses of ANG II (20, 50, and 100 ng/kg) and phenylephrine (2, 5, and 10 μg/kg) were similar in the two groups. However, Dex lambs displayed greater decreases in MABP in response to ganglionic blockade with tetraethylammonium bromide (10 mg/kg; −30 ± 3 vs. −20 ± 3 mmHg,P< 0.05) and greater increases in MABP after nitric oxide synthase blockade withNG-nitro-l-arginine (25 mg/kg; 23 ± 3 vs. 13 ± 2 mmHg,P< 0.05) compared with control lambs. By in vitro wire myography, mesenteric and femoral artery microvessel contractile responses to KCl were similar, whereas responses to endothelin (in mesenteric) and norepinephrine (in femoral) were significantly attenuated in Dex lambs compared with controls. Femoral vasodilatory responses to forskolin and sodium nitroprusside were similar in the two groups (n= 4). These findings suggest that resetting of the baroreflex, accompanied by increased sympathetic activity and altered nitric oxide-mediated compensatory vasodilatory function, may be important contributors to programming of hypertension.
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高血压前期和高血压 Dahl 遗传盐敏感大鼠心率异常压力感受反射控制
影响因子：
8.3
作者：
F. Gordon;H. Matsuguchi;A. Mark
通讯作者：
A. Mark
糖皮质激素和神经元功能的发育：产前地塞米松暴露对中枢去甲肾上腺素能活性的影响。
DOI：
10.1159/000243761
发表时间：
1992
期刊：
Biology of the neonate
影响因子：
--
作者：
T. Slotkin;S. Lappi;E. McCook;M. I. Tayyeb;J. Eylers;F. Seidler
通讯作者：
F. Seidler
DOI：
10.1152/ajpregu.00369.2005
发表时间：
2005-10
期刊：
American journal of physiology. Regulatory, integrative and comparative physiology
影响因子：
--
作者：
R. Roghair;J. Segar;Ram V. Sharma;M. Zimmerman;D. Jagadeesha;E. Segar;T. Scholz;F. Lamb
通讯作者：
R. Roghair;J. Segar;Ram V. Sharma;M. Zimmerman;D. Jagadeesha;E. Segar;T. Scholz;F. Lamb
影响因子：
37.8
作者：
Curhan, GC;Chertow, GM;Stampfer, MJ
通讯作者：
Stampfer, MJ
DOI：
10.7326/0003-4819-130-4_part_1-199902160-00005
发表时间：
1999-02-16
影响因子：
39.2
作者：
Rich-Edwards, JW;Colditz, GA;Manson, JE
通讯作者：
Manson, JE