[Effect of noradrenergic stimulation on the peripheral venous concentrations of thyroxine and triiodothyronine in young test subjects with normal metabolism].

The influence of intravenous noradrenalin infusions in increasing dosages lasting 60 minutes on the peripheral venous total T3- and total T4-concentrations of blood, blood pressure and heart rate was established on 5 test persons during a period of 110 minutes. Immediately after the addition of 0.12 micrograms NA/kg Kgw./min an increasing tendency of the T4-concentration in the venous blood occurred, respectively. Under influence of higher NA-doses (0.20 and 0.33 micrograms/kg Kgw./min) the noradrenergically induced T4-increase (p < 0.05) with average increases of the T4-level by 28.7 and 22.3%, respectively, in comparison to the initial values was statistically secured. The total T3-concentration did not show any statistically secure changes under NA-infusion. The fundamental possibilities of an influence of the intravenously applied NA on the production of the hormone of the thyroid gland, the secretion of the thyroid hormone and the peripheral conversion are discussed. Using findings of animal experiments the supposition of the immediate influence of the NA on the follicle cells of the thyroid gland and the secretory process gains importance. The clinical importance of the adrenergic modulation of the thyroxin secretion for the clinician is discussed.