Prolactin, renin and catecholamines in essential hypertension

In 40 male patients with essential hypertension less than the age of 36 years, the plasma prolactin (PRL), plasma renin activity (PRA) and plasma catecholamines (noradrenaline (NA) and adrenaline (A)) were determined simultaneously. Those levels were significantly increased compared to the levels in 14 age-matched healthy male control subjects. Furthermore, there were significant correlations between the PRL and plasma NA or PRA (p<0.05 in each case), and between the PRA and plasma NA (p<0.05). However, no significant relationships were observed between systolic or diastolic blood pressure and PRL, plasma NA or PRA. These findings indicate that the central dopaminergic activity is reduced in a number of young adults with essential hypertension, and that in the patients with the reduced central dopaminergic actvity, the peripheral sympathetic activity is stimulated and PRA is also increased probably due to the increased peripheral sympathetic activity, and the possibility exists that such changes are related to the development of hypertension.