title: L-Dopa Stimulates Cortisol Secretion through Adrenocorticotropic Hormone Release in Short Children.
abstract: OBJECTIVE
  We recently showed that L-Dopa administration is a potent stimulator of cortisol secretion in children with short stature. Herein, we examined whether adrenocorticotropic hormone (ACTH) is implicated in the mechanism by which cortisol is stimulated during the L-Dopa test.
  
  
  METHODS
  Nineteen children with short stature who fulfilled the auxological criteria for growth hormone (GH) deficiency and had a subnormal GH response to glucagon stimulation underwent a second GH stimulation test (L-Dopa test). Serum GH, cortisol and plasma ACTH were determined at baseline and every 30 min up to 120 min after oral L-Dopa administration. Peak values of GH >10 ng/ml, cortisol >18 μg/dl and ACTH >52 pg/ml were considered as normal response.
  
  
  RESULTS
  Normal response rates were 10.5% (2/19) for GH, 94.7% (18/19) for cortisol and 68.4% (13/19) for ACTH. Among the children with a normal response in ACTH, its concentration increased from a basal value (mean ± standard deviation) of 23.3 ± 9.6 to 290.3 ± 221 pg/ml, almost always 90-120 min after L-Dopa administration. Mean peak cortisol was 36.2 ± 9.1 μg/dl, and it peaked almost simultaneously with ACTH.
  
  
  CONCLUSIONS
  Our data suggest a stimulatory effect of the dopaminergic system on the hypothalamic-pituitary-adrenal axis.
authors.affiliation: Third Department of Pediatrics, University of Athens School of Medicine, x2018;Attikon' University Hospital, Athens, Greece.
authors.forename: Chrisanthi
authors.initials: C
authors.lastname: Marakaki
authors.forename: Dimitrios T
authors.initials: DT
authors.lastname: Papadimitriou
authors.forename: Kleanthis
authors.initials: K
authors.lastname: Kleanthous
authors.forename: Anna
authors.initials: A
authors.lastname: Papadopoulou
authors.forename: Anastasios
authors.initials: A
authors.lastname: Papadimitriou
mesh_terms: D000293:Adolescent; D000324:Adrenocorticotropic Hormone / Q000097:blood / Q000378:metabolism*; D001827:Body Height; D002648:Child; D002675:Child, Preschool; D015259:Dopamine Agents / Q000494:pharmacology*; D004392:Dwarfism / Q000175:diagnosis; D005260:Female; D005934:Glucagon / Q000494:pharmacology; D019382:Human Growth Hormone / Q000172:deficiency; D006801:Humans; D006854:Hydrocortisone / Q000097:blood / Q000378:metabolism*; D007980:Levodopa / Q000494:pharmacology*; D008297:Male; D011446:Prospective Studies; D013268:Stimulation, Chemical
chemical_list: D015259:Dopamine Agents; D019382:Human Growth Hormone; D007980:Levodopa; D000324:Adrenocorticotropic Hormone; D005934:Glucagon; D006854:Hydrocortisone