Abstract
A patient with essential hypertension receiving the oral administration of acebutolol, aβ1-selective adrenergic blocker, showed a marked increase in urinary 17-ketosteroid (17-KS) excretion determined by Zimmermann's method. Since the normal concentration of each fraction of 17-KS was found in this case by gas chromatography, the possibility of an abnormality in steroid metabolism could be excluded from the mechanism of the increase in the measured value for urinary 17-KS. In the urine samples from patients treated with acebutolol, acebutolol and acetylated acebutolol, a main metabolite acebutolol, were found equally among them. Moreover, acebutolol acetylated acebutolol resulted in a dose-dependent increase in 17-KS by Zimmermann's method in phosphate buffered saline or in a urine sample. However, the otherβ-blockers, such as propranolol, alprenolol and oxprenolol did not show any effect on the determined value for urinary 17-KS.
Thus it was concluded that the activated methylene group of acebutolol and acetylated acebutolol may interfere with the measured values obtained by Zimmermann's method.
