Ketotic Hypoglycemia: An Amino Acid Substrate Limited Disorder*

Publisher Website
Google Scholar
Abstract
Glucose, lactate, pyruvate, ketone bodies (β-hydroxybutyrate + acetoacetate), glycerol, plasma amino acids, cortisol, growth hormone, insulin and glucagon were determined at frequent intervals throughout a fast in 10 ketotic hypoglycemic (KH) and 6 normal children. In the KH children, plasma glucose was 27.4 ± 2.6 mg/100 ml, ketone bodies were 5.95 ± 0.86 mM, and glycerol was 232 ± 34 μm as compared to 75.7 ± 2.9 mg/100 ml, 1.12 ± 0.19 mm, and 121 ± 13 μm respectively, for the normals at 20 hr fasting (p < 0.01 for all values). After 14 hr fasting little or no insulin was detectable in either group. Total gluconeogenic amino acids were significantly lower (p < 0.01) in the KH children when compared to normal at all points examined (3024 ± 118 vs 2354 ± 121 μm at 0 time and 1743 ±112 vs 1161 ± 69 μm at 20 hr fasting). Branched chain amino acids were significantly higher in the KH children (p < 0.05) at 20 hr fasting (384 ± 35 vs 567 ± 41 μm). No differences in lactate or pyruvate were found. At the time the KH children were hypoglycemic, cortisol was 27 ± 3 vs 8.8 ± 2.0 μg/100 ml for normal children, growth hormone was 11 ± 4 vs 2 ± 0.2 ng/ml (p < 0.05), and glucagon was 340 ± 74 vs 92 ± 22 μμg/ml (p < 0.05). With hypoglycemia, low insulin and elevated ketone bodies and glycerol are appropriate responses. Elevated cortisol, growth hormone and glucagon reflect normal responses to the hypoglycemic stress and further evidence that these hormones do not play an etiologic role in this disorder. Low gluconeogenic amino acids would appear to be the rate limiting event due either to decreased amino acid mobilization or increased glucose utilization.

This publication has 0 references indexed in Scilit: