The effect of DPT inoculation on the hormonal control of glucose homeostatis in children recovered from malnutrition

RESUMO

The effect of a controlled stress (DPT inoculation) on the hormonal control of glucose homeostasis was investigated in children nutritionally rehabilitated from severe malnutrition. The age range of the 15 children studied was 6-26 months. Plasma insulin (INS), growth hormone (GH) and interleukin-1 (IL-1) were measured by radioimmunoassay; plasma glucose (GLU) by a glucoseoxidase method; and red cell insulin binding (%SB) was determined, using A-14 monoiodinated insulin. Measurements were made on two occasions: (T-O) at 10 a.m.,12 hr before DPT inoculation, and (T-36) 36 hr. after inoculation. On both occasions, 4 hr post-prandial blood samples were used, and the mean body temperature(T) on the day of the test was determined. Red cell insulin binding (%SB) was significantly higher at T-36 than at T-O (16.8 ñ 1.7 vs 12.1 ñ 1.2 (14), p=0.005). (Results were expressed as mean ñ SEM, numbers of paired observations in parentheses). The higher %SB after DPT was accompanied by an increase in the number of receptor sites (S) (29.05 ñ 6.5 vs 15.6 ñ 2.5 (14),p=0.025). However, insulin receptor affinity (K x 10(9)M(-1)) was decreased 0.7 ñ 0.1 vs 1.5 ñ 0.3(14), p=0.008). There were no significant differences in the plasma levels of insulin, glucose and interleukin-1, but plasma growth hormone (*U/ml) was increased after DPT, (18.0 ñ 3.0 vs 11.5 ñ 1.2 (13), p=0.04). Body temperature (-C) was also significantly increased after DPT,(99.9 ñ 0.4 vs 98.3 ñ 0.2(14), p=0.006). The change in plasma glucose from T-O to T-36 tended to be associated with both a change in plasma insulin (p=0.06) and plasma growth hormone (p=0.07). Increased insulin binding, as one index of increased insulin sensitivity during fever, can contribute to a reductionin blood glucose. However, the elevation in plasma growth hormone cold buffer the hypoglycaemic effect of insulin, and help to maintain glucose homeostasis