Involvement of catecholamines and serotonin in human hypertension

Lumber cerebrospinal fluid (CSF) concentrations of metabolites of noradrenaline, adrenaline and serotonin were estimated in patients of sustained hypertension (n = 20), and healthy controls (n = 15). Platelet uptake of serotonin and its basal contents were also estimated in the same individuals. CSF 5-hydroxy indole acetic acid level (5-HIAA) (major metabolite of serotonin) was significantly higher in hypertensives than controls (p less than .01). CSF 3-methoxy, 5-hydroxy phenyl glycol (MHPG) (major metabolite of adrenaline and noradrenaline) level was also raised significantly in cases of hypertension (p less than .01). However, platelet uptake of serotonin as well as its basal contents in hypertension were significantly lower than controls (p less than .01). It can thus be postulated that there exists an increased central serotonergic and catecholaminergic activity in hypertension. Furthermore, alterations observed in platelet serotonin uptake and its basal content suggest the involvement of platelet serotonergic system in hypertension.