UNTERSUCHUNGEN ÜBER DIE TETRAHYDROALDOSTERON AUSSCHEIDUNG IM KINDESALTER DURCH GASCHROMATOGRAPHIE MIT ELEKTRONENEINFANGDETEKTOR (ECD)

Abstract

ABSTRACT Tetrahydroaldosterone-(THAldo)-glucuronide is the most important metabolite of aldosterone in the urine. According to Nicolis & Gabrilove (1969) we developed a GLC method for the determination of THAldo. The method includes the following steps: Enzymatic hydrolysis, extraction with ethylacetate, formation of γ-lactone, first TLC, formation of heptafluorobutyrate (HFB), second TLC, gas liquid chromatography (GLC) with electron capture detector (ECD), correction for losses by the internal 3H-THAldo standard. As little as 3 ng/sample can be detected with a coefficient of variation of < 10%. The paper presents more than 300 THAldo determinations during infancy and childhood. At the age of 5–30 days there is a significant (P < 0.01) peak of the THAldo excretion. The biological meaning of these high THAldo values in the early days of life is not clear at the present time. The peak is independent of the nutrition. After the age of 12 months the mean THAldo excretion is about 30 μg/m2/d. There is a circadian rhythm with a peak in the late morning. The dependence of the THAldo excretion on the sodium intake in childhood is the same as in adults. After potassium loading there is likewise a strong increase in the THAldo excretion. In a child suffering from Addison's disease we found about 30% of the substituted aldosterone as THAldo-glucuronide in the urine. As well angiotensin as ACTH induce an increase of the THAldo excretion. After dexamethasone there is a decrease of THAldo excretion indicating again an ACTH dependence of the aldosterone secretion. Children suffering from nephrotic syndrome during the active phase of the disease show very high values of THAldo in the urine. Under treatment with corticosteroids the THAldo excretion decreases depending on the remission. Treatment with both furosemide and potassium induces again a sharp increase of the THAldo excretion.