Thörne A
Department of Surgery, Huddinge University Hospital, Karolinska Institute, Stockholm, Sweden.
Acta Chir Scand Suppl. 1990;558:6-59.
Diet-induced thermogenesis (DIT) denotes the increase in energy expenditure that occurs in response to food ingestion. The purpose of the present study was to examine the possible influence of age, training state and sympatho-adrenal activity on the early phase of DIT in healthy individuals and further to study whether the magnitude of DIT is reduced in human obesity and, if so, to what extent DIT is influenced by weight reduction induced by surgical treatment, i.e. gastric banding or vertical banded gastroplasty. In addition, the effect of an artificial abdominal insulation on the DIT reaction was examined in healthy subjects in order to find out if the spontaneously enhanced thermal insulation of the body in obese individuals may be accompanied by a reduced DIT. The subjects were studied in the basal state and during 2-3 hours after a mixed meal. The energy expenditure was determined by indirect calorimetry. Blood temperature and blood flow in the hepatic vein were measured and splanchnic oxygen uptake and blood-drained heat from the splanchnic region were calculated. The meal was in liquid form, consisting of 17% kJ protein, 28% kJ lipids and 55% kJ carbohydrates, corresponding to either 60% of the individually measured 24-h resting energy expenditure or to 40% of the individually predicted basal metabolic rate. DIT was expressed as the average increase in energy expenditure above the basal level (means +/- SEM). After a 60% meal it was less (21 +/- 3%, P less than 0.01) in 8 elderly (70 +/- 1 years) and 7 middle-aged (51 +/- 3 yrs) individuals (24 +/- 2%, P less than 0.05) than in 10 young (27 +/- 1 yrs) men (29 +/- 2%). Its magnitude was similar (n.s.) in 7 well-trained men with a higher (58 +/- 2 ml/min/kg BW) maximal oxygen uptake (25 +/- 2%) and 7 sedentary individuals with a lower (39 +/- 2 ml/min/kg BW) aerobic capacity (29 +/- 2%). An intravenous pharmacological inhibition of the beta-adrenergic receptor function failed to influence the DIT in 10 men, irrespective of whether the beta-blockade was instituted by a selective-beta-1 antagonist (atenolol) or a non-selective blocker (propranolol). The DIT was 29 +/- 1% with and 29 +/- 2% (n.s.) without a beta-blockade and it was 29% in 2 subjects after 1 week of oral propranolol medication.(ABSTRACT TRUNCATED AT 400 WORDS)
饮食诱导产热（DIT）是指因食物摄入而发生的能量消耗增加。本研究的目的是检测年龄、训练状态和交感 - 肾上腺活动对健康个体DIT早期阶段的可能影响，并进一步研究人类肥胖时DIT幅度是否降低，以及如果降低，手术治疗（即胃束带术或垂直带胃成形术）引起的体重减轻对DIT的影响程度。此外，在健康受试者中检测人工腹部隔热对DIT反应的影响，以确定肥胖个体中身体自发增强的隔热是否可能伴随着DIT降低。受试者在基础状态以及混合餐后2 - 3小时进行研究。能量消耗通过间接测热法测定。测量肝静脉中的血液温度和血流量，并计算内脏氧摄取和来自内脏区域的引流热。餐食为液体形式，由17%千焦蛋白质、28%千焦脂质和55%千焦碳水化合物组成，相当于个体测量的24小时静息能量消耗的60%或个体预测基础代谢率的40%。DIT表示为高于基础水平的能量消耗平均增加量（均值±标准误）。在摄入相当于60%量的餐食后，8名老年人（70±1岁）和7名中年人（51±3岁）的DIT（分别为21±3%，P<0.01和24±2%，P<0.05）低于10名年轻人（27±1岁）（29±2%）。7名训练有素、最大摄氧量较高（58±2毫升/分钟/千克体重）的男性（25±2%）和7名有氧能力较低（39±2毫升/分钟/千克体重）的久坐个体（29±2%）的DIT幅度相似（无统计学差异）。静脉内给予β - 肾上腺素能受体功能的药理学抑制未能影响10名男性的DIT，无论β受体阻滞剂是由选择性β1拮抗剂（阿替洛尔）还是非选择性阻滞剂（普萘洛尔）引起。有β受体阻滞剂时DIT为29±1%，无β受体阻滞剂时为29±2%（无统计学差异），2名受试者口服普萘洛尔1周后DIT为29%。（摘要截断于400字）
