1.
Short-Term Effects of Growth Hormone on Lipolysis, Glucose and Amino Acid Metabolism Assessed in Serum and Microdialysate of Healthy Young Men.
Krebs, A, Baum, A, Doerfer, J, Gempel, K, Wurm, M, Brichta, C, Sass, JO, Winkler, K, Schwab, KO
Experimental and clinical endocrinology & diabetes : official journal, German Society of Endocrinology [and] German Diabetes Association. 2020;(12):819-826
Abstract
OBJECTIVE We investigated direct effects of a therapeutic growth hormone dose on lipolysis, glucose and amino acid metabolism. METHODS This crossover microdialysis trial involved six healthy male volunteers receiving single subcutaneous injections of both growth hormone (0.035 mg/kg) and placebo (0.9% sodium chloride). The investigation comprised three test days with standard diet. The first day served for adaptation, the second and third one for determining study data during 9 night hours with or without growth hormone. Abdominal subcutaneous microdialysate and blood were continuously collected and forwarded to a separate room next door where hourly taken samples were centrifuged and frozen until analysed. RESULTS Growth hormone achieved the peak serum level after 3 h followed by a plateau-like course for the next 6 h. Glycerol in microdialysate started to rise 2 h following growth hormone injection achieving significance compared to placebo after 9 h (P<0.05). Serum glycerol increased 4 h after growth hormone administration achieving significance after 6 h (P<0.05). Glucose and amino acid concentrations showed neither in microdialysate nor in serum significant differences between growth hormone and placebo. Serum values of insulin and C-peptide revealed no significant difference between growth hormone and placebo. SUMMARY AND CONCLUSION As the result of a high single subcutaneous dose of GH, persistent lipolysis can be shown in continuously collected microdialysate and blood, but no indication for gluconeogenesis or protein anabolism.
2.
Induction of early meconium evacuation promotes feeding tolerance in very low birth weight infants.
Shim, SY, Kim, HS, Kim, DH, Kim, EK, Son, DW, Kim, BI, Choi, JH
Neonatology. 2007;(1):67-72
Abstract
BACKGROUND A delay in reaching full enteral feeding is linked to poorer outcome in preterm neonates. Meconium retention has been viewed as a cause of bowel dysfunction in very low birth weight infants (VLBWI). Thus, adequate evacuation of meconium could help to promote feeding tolerance. OBJECTIVES Our goal was to determine the effect of the induction of early meconium evacuation on feeding tolerance in VLBWI. METHODS An observational study involving two subsequent periods was performed in inborn infants with birth weights of <1,500 g, before (control) and after (study) the induction of early meconium evacuation by routine glycerin enema. The total duration of these periods was from January 2003 to December 2005. To evaluate feeding tolerance, we measured time to achieve full enteral feeding. Complications such as sepsis and necrotizing enterocolitis were compared. RESULTS The study group achieved full enteral feeding significantly faster than the control group (hazard ratio (HR) = 2.9; 95% confidence interval (CI) = 1.8-4.8), and this effect was more definite in infants with a birth weight of <1,000 g (HR = 4.6; 95% CI = 1.9-11.1). The study group passed first meconium faster than the control group (median = 1.4 vs. 3.7 days; p < 0.001). Sepsis, especially as determined by positive culture in central venouscatheter, was significantly reduced in the study group (7.7 vs. 27.8%; p = 0.02). CONCLUSIONS The induction of early meconium evacuation had a significantly positive effect on feeding tolerance and sepsis prevention in VLBWI.
3.
Glycerol hyperhydration: physiological responses during cold-air exposure.
O'Brien, C, Freund, BJ, Young, AJ, Sawka, MN
Journal of applied physiology (Bethesda, Md. : 1985). 2005;(2):515-21
Abstract
Hypohydration occurs during cold-air exposure (CAE) through combined effects of reduced fluid intake and increased fluid losses. Because hypohydration is associated with reduced physical performance, strategies for maintaining hydration during CAE are important. Glycerol ingestion (GI) can induce hyperhydration in hot and temperate environments, resulting in greater fluid retention compared with water (WI) alone, but it is not effective during cold-water immersion. Water immersion induces a greater natriuresis and diuresis than cold exposure; therefore, whether GI might be effective for hyperhydration during CAE remains unknown. This study examined physiological responses, i.e., thermoregulatory, cardiovascular, renal, vascular fluid, and fluid-regulating hormonal responses, to GI in seven men during 4 h CAE (15 degrees C, 30% relative humidity). Subjects completed three separate, double-blind, and counterbalanced trials including WI (37 ml water/l total body water), GI (37 ml water/l total body water plus 1.5 g glycerol/l total body water), and no fluid. Fluids were ingested 30 min before CAE. Thermoregulatory responses to cold were similar during each trial. Urine flow rates were higher (P = 0.0001) with WI (peak 11.8 ml/min, SD 1.9) than GI (5.0 ml/min, SD 1.8), and fluid retention was greater (P = 0.0001) with GI (34%, SD 7) than WI (18%, SD 5) at the end of CAE. Differences in urine flow rate and fluid retention were the result of a greater free water clearance with WI. These data indicate glycerol can be an effective hyperhydrating agent during CAE.