We have evaluated the effects of the combined administration of Galanin (Gal) plus growth hormone- releasing hormone (GHRH) and of pyridostigmine (PD), a cholinergic agonist, plus Gal on GH secretion in 15 children (12 males and three females, age 7.7-14.5 y) with short stature. Children were subdivided into two groups. In group 1 (n=7) Gal (15 µg/kg h i.v.) plus GHRH (1 µg/kg i-v.) administration induced a higher GH rise (peak=73.1 ± 10.2 ng/mL, mean ± SD; area under the curve (AUC)=531.9 ± 78.7 ng. min. mL-1) than did GHRH alone (peak=38.9 ± 26.5 ng/mL,p<0.05; AUC=256.9 ± 165.6 ng/mL/min-1,p<0.005). Gal had a synergistic effect on the GHRH-induced GH response because the GHRH plus Gal AUC response was significantly higher (p<0.01) than the sum of the areas of response to GHRH and Gal alone. In group 2 (n=8) PD administration (60 mg/kg p.o.) had no significant effects on the Gal-induced GH secretion (peak=14.9 ± 8.8 and 16.0 ± 9.8 ng/mL after Gal and PD + Gal, respectively; AUC=91.2 ± 52.1 and 125.2 ± 83.6 ng. mL. min-1after Gal and PD + Gal, respectively). Our results confirm the ability of Gal to stimulate GH secretion in children, and strengthen the view that its mechanism of action involves modulation of endogenous somatostatin release.