Effects of weight cycling on urinary catecholamines: sympathoadrenal role in refeeding hypertension
Effects of weight cycling on urinary catecholamines: sympathoadrenal role in refeeding hypertension
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DOI：
10.1097/00004872-199816121-00022
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发表时间：
1998-12-01
影响因子：
4.9
通讯作者：
Bedol, D
中科院分区：
文献类型：
--
作者：
Ernsberger, P;Koletsky, RJ;Bedol, D
目的：我们试图确定交感神经系统是否在极低热量饮食（VLCD）后的高血压反应中起作用。在肥胖自发性高血压大鼠（SHROB）遗传性肥胖高血压模型中诱导体重减轻和恢复的设计周期。方法15 d VLCD（1/6基线热量）与4-6周随意补饲3个周期交替进行。对照SHROB随意进食，VLCD前后24 h采集尿液，用放射酶法测定儿茶酚胺含量。在收集尿液的同时测量尾袖血压和体重，收集肾脏进行α(2)-肾上腺素能受体密度测定。结果VLCD诱导大鼠体重快速下降，但在复喂期间体重恢复；限热期间血压下降，但在复喂期间血压高于基线；体重循环期间尿中去甲肾上腺素、肾上腺素和多巴胺的排泄量变化数倍。尿儿茶酚胺的变化与血压的变化相似，在热量限制时下降，在重新进食时反弹；多巴胺在体重减轻时下降幅度最大，在体重恢复时上升，而肾上腺素的变化最小，去甲肾上腺素的变化居中。体重循环使血压高于初始基线，在体重循环SHROB的肾髓质和皮质中α(2)-肾上腺素能受体的密度下降，与过度刺激引起的受体下调一致。结论SHROB患者体重恢复过程中高血压的加重与交感肾上腺活性的持续激活相一致，反映在尿儿茶酚胺排泄终肾上腺素能受体下调。[J] .中国医学工程学报，1998,16(2):391 - 391。
Objectives We sought to determine whether the sympathetic nervous system plays a role in the hypertensive response to refeeding from a very low-calorie diet (VLCD).Design Cycles of weight loss and regain were induced in the obese spontaneously hypertensive rat (SHROB) model of genetic obese hypertension.Methods A 15-day VLCD (1/6 of baseline calories) was alternated with 4-6 weeks of ad libitum chow refeeding for three cycles. Control SHROB ate chow ad libitum, Urine was collected for 24 h before and after each period of VLCD, and catecholamines were measured radioenzymatically. Tail cuff blood pressures and body weight were measured in parallel with urine collections, Kidneys were collected for assay of alpha(2)-adrenergic receptor density.Results VLCD induced rapid weight loss, but all the lost weight was regained during refeeding, Blood pressure fell during caloric restriction, but rose above baseline during refeeding, Urinary excretion of norepinephrine, epinephrine and dopamine changed several fold during weight cycling. Urinary catecholamines paralleled the changes in blood pressure, falling during caloric restriction and rebounding during refeeding, Dopamine showed the greatest decreases during weight loss and rises during weight regain, whereas epinephrine changed the least and norepinephrine was intermediate. Weight cycling elevated blood pressure above the initial baseline throughout the rapid weight gain phase of refeeding, The density of alpha(2)-adrenergic receptors was decreased in both the renal medulla and cortex of weight cycled SHROB, consistent with receptor down-regulation owing to overstimulation.Conclusions The exacerbations of hypertension during weight regain in SHROB coincide with sustained activation of sympathoadrenal activity, as reflected in urinary catecholamine excretion end adrenergic receptor down regulation. J Hypertens 1998, 16:2001-2005 (C) 1998 Lippincott Williams & Wilkins.