Plasma noradrenaline in hyperthyroidism and hypothyroidism
Premel-Cabic, A.; Gétin, F.; Turcant, A.; Rohmer, V.; Bigorgne, J.C.; Allain, P.
Presse Medicale 15(32): 1625-1627
1986
ISSN/ISBN: 0755-4982 PMID: 2949210 Document Number: 281465
Plasma noradrenaline concentrations (NA) were measured in 11 hypothyroid patients, 24 hypothyroid patients and 30 normal subjects after 30 minutes of supine rest and after 5 minutes of standing. Observed noradrenaline levels, after rest as well as after standing, were significantly higher in hypothyroid patients (NA rest = 0.66 +/- 0.35 microgram/l, NA standing = 1.26 +/- 0.70 micrograms/l) and significantly lower in hyperthyroid patients (NA rest = 0.22 +/- 0.13 micrograms/l, NA standing = 0.37 +/- 0.20 microgram/l) than in normal subjects (NA rest = 0.32 +/- 0.13 microgram/l, NA standing = 0.55 +/- 0.20 microgram/l). The increase in noradrenaline with standing, when expressed in percent, was similar for the three groups studied (about 100%). These results suggest that a sympathetic nervous system adaptation occurs in hyperthyroidism and hypothyroidism as a compensatory phenomenon to the direct effect of thyroid hormones on the heart.