Sekhar R V, Shetty P S, Kurpad A V
Department of Physiology, St. John's Medical College, Bangalore.
Indian J Med Res. 1998 Dec;108:265-71.
The parasympathetic nervous system (PNS) has been shown to be important in the mediation of diet induced thermogenesis (DIT). Chronically energy deficient (CED) subjects have a high resting parasympathetic tone, which could lead to a greater than expected DIT. DIT was studied in chronically energy deficient adult men and healthy age-matched volunteers (6 controls, 7 CED subjects) with an isocaloric (600 kcal) meal given by the oral and intravenous (i.v.) routes on two consecutive days, on a crossover basis. The resting metabolic rate (RMR) and the DIT were measured over 6 h, along with cardiovascular, biochemical and anthropometric parameters. Anthropometrically (height, weight, fat free mass, body mass index, mid upper arm circumference and sum of skinfolds), the CED group differed significantly from the well-nourished control group. There were no significant differences between the two groups in the basal state for metabolic (RMR, oxygen consumption, respiratory quotient), cardiovascular [blood pressure (BP), heart rate, cardiac output], and biochemical (plasma glucose, insulin and norepinephrine) parameters. The CED group had a significantly higher DIT response for both meal types when compared to the controls, when expressed as an absolute value and as a percentage response. However, the response was not significant when corrected for the meal size and body weight. There were also no significant differences between the two meal types in each group for the metabolic, cardiovascular and biochemical parameters during the DIT period, although, in general, the oral meal gave a larger DIT response compared to the i.v. meal. Both groups predominantly oxidised fat during the fasted stage and switched to carbohydrate oxidation when fed. It appears that, the previously demonstrated higher tone in the PNS, does not make a significant contribution to the thermic response of a meal in these subjects.
副交感神经系统（PNS）已被证明在饮食诱导产热（DIT）的调节中起重要作用。长期能量不足（CED）的受试者静息副交感神经张力较高，这可能导致DIT高于预期。在成年男性慢性能量不足者和年龄匹配的健康志愿者（6名对照者，7名CED受试者）中进行了DIT研究，连续两天采用交叉设计，通过口服和静脉注射（i.v.）途径给予等热量（600千卡）餐食。在6小时内测量静息代谢率（RMR）和DIT，同时测量心血管、生化和人体测量参数。在人体测量方面（身高、体重、去脂体重、体重指数、上臂中部周长和皮褶厚度总和），CED组与营养良好的对照组有显著差异。两组在基础状态下的代谢（RMR、耗氧量、呼吸商）、心血管[血压（BP）、心率、心输出量]和生化（血浆葡萄糖、胰岛素和去甲肾上腺素）参数无显著差异。当以绝对值和百分比反应表示时，CED组对两种餐食类型的DIT反应均显著高于对照组。然而，校正餐量和体重后，该反应无统计学意义。在DIT期间，每组两种餐食类型的代谢、心血管和生化参数也无显著差异，尽管一般来说，口服餐食比静脉注射餐食产生的DIT反应更大。两组在禁食阶段主要氧化脂肪，进食时则转换为碳水化合物氧化。看来，先前证明的PNS较高张力对这些受试者餐食的热反应没有显著贡献。
