title: Evaluation of sympathetic nervous system and adrenomedullary activity in normal children.
abstract: In 22 healthy children heart rate, blood pressure and plasma levels of epinephrine (E) and norepinephrine (NE) were evaluated under basal conditions and in response to standing (5 min). Basal plasma E and NE levels found in these children were (means +/- S.E.M.) 139 +/- 17.9 pg/ml and 236 +/- 31.0 pg/ml respectively. Ten out of the 22 children reported dizziness and discomfort by the end of the 5 min standing period. These children showed not only a greater decrease in both systolic and diastolic blood pressure but also a lower basal heart rate, a tendency to higher basal NE levels and a blunted plasma NE response (23 +/- 7%) when compared with children not reporting symptoms (60 +/- 9%, P less than 0.01). Plasma E levels also showed an increment although a wide range of individual responses was observed in both groups.
mesh_terms: D000313:Adrenal Medulla / Q000294:innervation*; D001794:Blood Pressure; D002648:Child; D002675:Child, Preschool; D004837:Epinephrine / Q000097:blood; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D009638:Norepinephrine / Q000097:blood; D011187:Posture; D013564:Sympathetic Nervous System / Q000502:physiology*
chemical_list: D009638:Norepinephrine; D004837:Epinephrine