PT - JOURNAL ARTICLE AU - Cuche, J. L. AU - Kuchel, O. AU - Barbeau, A. AU - Genest, J. TI - Urinary homovanillic acid, dopamine and norepinephrine excretion in patients with essential hypertension DP - 1975 Feb 22 TA - Canadian Medical Association Journal PG - 44306--44306 VI - 112 IP - 4 4099 - http://www.cmaj.ca/content/112/4/44306.short 4100 - http://www.cmaj.ca/content/112/4/44306.full SO - CMAJ1975 Feb 22; 112 AB - Urinary excretion of dopamine, norepinephrine and homovanillic acid was measured in normotensive subjects and in patients with either labile of stable hypertension under conditions controlled for posture, sodium and potassium intake and time of day. Mean homovanillic acid excretion was 313.5 plus or minus 77.7 (SE) mug/4h in the normotensive patients. Mean values for the patients with labile or stable hypertension were significantly greater, at 2506 plus or minus 476 mug/4 h (P smaller than 0.001) and 795 plus or minus 170 mug/4 h (P smaller than 0.01), respectively. Urinary excretion of dopamine and norepinephrine tended to be elevated in patients with labile hypertension when compared with values in the control subjects and the patients with stable hypertension. The data are compatible with the hypothesis of adrenergic hyperactivity in labile hypertension and underline the biochemical heterogeneity of essential hypertension. Because the overlapping of values between control subjects and patients with labile hypertension was minimal, it is proposed that an elevated valve for urinary homovanillic acid could be used as a biochemical marker to identify the patients with labile hypertension.