We have evaluated the effect of pubertal maturation on the GH response to growth hormone releasing hormone (GHRH), pyridostigmine (PD), and the combined administration of PD + GHRH in a group of short normal children. Fifteen were prepubertal (13 boys and 2 girls, age 5.0–12.5 yr), 10 were early pubertal (8 boys and 2 girls, age 11.5–16.9 yr in Tanner stage 2–3 of pubertal maturation), and 6 were late pubertal (6 boys and 2 girls, age 13.6–17.1 yr in Tanner stage 4–5 of pubertal maturation). All subjects were tested on three occasions with GHRH 1–29 (1 μg/Kg iv), PD (60 mg po) and PD + GHRH (60 mg PD administered orally 60 min before GHRH). Peak GH levels after GHRH, PD, and PD + GHRH in the prepubertal children (16.0 ± 2.8, 8.1 ± 1.3 and 51.1 ± 5.5 ng/ml, mean ± SE, respectively) were not different from those observed in the early pubertal (18.4 ± 2.1, 9.1 ±1.9 and 41.2 ± 5.6 ng/ml, respectively) and in the late pubertal group (14.9 ± 2.3, 13.1 ± 2.4 and 42.6 ± 2.9 ng/ml, respectively). Evaluation of the area under the curve (AUC) also showed no difference in the GH response to GHRH, PD and PD + GHRH between the three groups studied. These results confirm that the combination PD + GHRH is a powerful test to study the GH secretory capacity of the pituitary, and show that pubertal maturation has no effect on the GH response to this test.
ASJC Scopus subject areas
- Endocrinology, Diabetes and Metabolism