Total urinary catechol excretion in cardiovascular and other clinical conditions.

Although colorimetry (method of Shaw) permits neither a differentiation of epinephrine and norepinephrine nor their separation from other catechols, it reveals the total urinary catechol excre-tion, including those portions which were inactivated in the body. No significant aklnormalities were found in arterial hypertension, in congestive heart failure, after myocardial infarction and during emotional stress. Thoracolumbar sympathectomy depressed total catechol excretion temporarily. In renal uremia, the regularly demonstrable elevation of the blood catechols was paralleled by a diminution of l{ conjugated catechols in the urine. It appears to be due to renal retention. T HE increasing appreciation of the patho-genic importance of sympathoadrenal neurosecretion in cardiovascular pathology has prompted various attempts to gage the state of function of the sympathetic nervous system and of the adrenal medulla by means of assay of epinephrine, norepinephrine and related compounds in the urine. Holtz and co-workers1 detected increased amounts of pharmacodynamically active catecholamines in the urine of 16 out of 23 patients with arterial hypertension. This was confirmed by Krone-berg and Schumann2 but Goldenberg and Rapport3 recorded abnormally high values in only 2 out of 14 patients with essential hyper-tension. The colorimetric test of Shaw4 permits the isolation and recovery of all chromogenic catechol compounds.5 It reveals the presence in the urine of chromogenic material far in excess of what can be assumed to be the combined amounts of active epinephrine, norepi-nephrine and hydroxytyramine3' 6,"7 In addition , acid hydrolysis intensifies the color reaction markedly.2' 6 It has been concluded, therefore, that the urine contains, beside the active material, considerable quantities of both free and conjugated derivatives of deam-an intact catechol nucleus. Using the colorimetric assay of total cate-chols in the nonhydrolyzed and hydrolyzed urines of normal and hypertensive individuals, Kroneberg and Schtimann2 did not observe any difference between the two groups regarding the nonconjugated chromogenic catechols but the conjugated catechols, as recovered by hydrolysis, appeared to be markedly augmented in the hypertensive group (average +73 per cent). Nuzum and Bischoff6 did not confirm the latter finding. In their series, no significant difference was apparent in the urines of normal and hypertensive subjects. Only in three patients with myocardial infarction did they observe an increased ratio of the readings from hydrolyzed and nonhydrolyzed urine.~ Shaw's so-called "specificity test" (color ratio of alkali-and acid-treated specimens), upon which Nuzum and Bischoff6 based their calculation of the absolute amounts of ex-creted epinephrine, is not suitable for the …