Age dimorphism in the association between growth-hormone status and the respiratory quotient

摘要: Objective: To investigate the impact of age on association between respiratory quotient (RQ) and growth-hormone (GH) secretion to acute lipolytic response an exogenous GH bolus. Research Methods Procedures: A cross-sectional study 36 non-obese healthy subjects (18 women 18 men) from two groups was used: “younger” (mean age, 29.5 years; range, 27 34 years) “older” 50.8 47 59 years). Endogenous by means deconvolution analysis 24-hour serum concentrations measured every 20 minutes. Resting RQ after a 12-hour overnight fast. The intravenous bolus (200 μg) assessed measuring levels free fatty acids as well changes in RQ. Additional measurements included body composition (regional computed tomography scan DXA) physical fitness (Vo2max). Results: did not differ groups: 0.81 ± 0.01 (young) vs. 0.82 (older; significant). Several estimates release correlated positively with younger group, whereas negative correlation detected older [GH production rate (μg/liter × kg) RQ: r = 0.62, p < (younger); −0.53; 0.02 (older)]. By regression analysis, 52% 58% variation could be explained status. After bolus, incremental nonesterified acid slightly higher individuals (p 0.09). Discussion: is significantly This positive individuals. moderately compared status should taken into account when investigating residual