title: L-dopa is a potent stimulator of cortisol in short children.
abstract: OBJECTIVE
  In this study, we evaluated the diagnostic usefulness of oral L-dopa as a stimulatory agent for cortisol.
  
  
  METHODS
  In 27 short children that were evaluated for possible growth hormone deficiency (GHD), the levels of serum GH and cortisol were determined after oral L-dopa administration and after i.m. glucagon administration. We defined cortisol concentrations >18 μg/dl (496 nmol/l) as adequate response. Peak GH concentration <10 ng/ml in both tests defined GHD.
  
  
  RESULTS
  Twenty-five out of the 27 children (93%) studied showed a normal cortisol response, i.e. a peak serum cortisol >18 μg/dl in the L-dopa test, whereas 19 children (70%) had a normal cortisol response after stimulation with glucagon. In the children with normal cortisol response in both tests, the mean peak serum cortisol concentration was 28.7 (SD 1.59) after L-dopa and 26.65 (SD 1.26) μg/dl after glucagon administration. There was no statistically significant difference in peak serum cortisol response to L-dopa between GH-deficient and GH-sufficient children [25.90 (SD 4.9) vs. 29.87 (SD 9.9) μg/dl, respectively].
  
  
  CONCLUSIONS
  These results clearly suggest that L-dopa administration is a potent stimulus for cortisol secretion at least in short children.
authors.affiliation: Third Department of Pediatrics, Attikon University Hospital, Athens, Greece.
authors.forename: C
authors.initials: C
authors.lastname: Marakaki
authors.forename: D T
authors.initials: DT
authors.lastname: Papadimitriou
authors.forename: A
authors.initials: A
authors.lastname: Papadopoulou
authors.forename: A
authors.initials: A
authors.lastname: Fretzayas
authors.forename: A
authors.initials: A
authors.lastname: Papadimitriou
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D004392:Dwarfism / Q000175:diagnosis; D005260:Female; D006130:Growth Disorders / Q000175:diagnosis; D019382:Human Growth Hormone / Q000172:deficiency*; D006801:Humans; D006854:Hydrocortisone / Q000097:blood / Q000378:metabolism*; D007223:Infant; D007980:Levodopa; D008297:Male
chemical_list: D019382:Human Growth Hormone; D007980:Levodopa; D006854:Hydrocortisone