Raised cerebrospinal fluid norepinephrine in some patients with primary hypertension.

Abstract

SUMMARY To test whether central neurogenic factors participate in blood pressure elevation in primary hypertension, we studied the concentrations of: norepinephrine, epinephrine and dopamine-beta-hydroxylase (DBH) in cerebrospinal fluid (CSF); and norepinephrine, epinephrine, DBH and plasma renin activity (PRA) in plasma of 22 subjects (seven with primary hypertension, 11 normotensive patients with non-systemic neurological disorders, and four with secondary hypertension). Plasma and CSF norepinephrine (NE) were increased in primary hypertensives compared to normotensives. Cerebrospinal fluid norepinephrine was related to diastolic blood pressure, and systolic blood pressure when normotensive and primary hypertensives were taken together. The CSF norepinephrine of primary hypertensive patients was correlated with natural log PRA. The CSF norepinephrine was correlated inversely with age in primary hypertensive patients but not in the normotensive subjects. The low CSF norepinephrine and epinephrine, despite markedly increased plasma NE and epinephrine, in two patients with pbeochromocytoma, indicate a blood-brain barrier for these neurohormones. The observations support the view that the central sympathetic nervous system is involved in the pathogenesis of primary hypertension, particularly in younger patients. 1 " Hyperactivity of the central sympathetic nervous system might raise plasma norepinephrine and lead to the development of hypertension. Because of an efficient blood-brain barrier to norepinephrine (NE) it seems possible to evaluate central nervous system NE release by measuring NE in cerebrospinal fluid (CSF). Therefore, in this study, we compared CSF NE concentrations from patients with primary hypertension with those from normotensive patients with various neurological disorders. We found increased NE in CSF and plasma from the hypertensive group, which suggests that central sympathetic hypertonicity is associated with raised peripheral sympathetic nerve tone and elevated blood pressure in younger patients with primary hypertension.

CSF sulfoconjugated catecholamines in man: Their relationship with plasma catecholamines

“…DA sulfate administered into the brain ventricle of rats also enters the blood stream (Buu et aL, 1982) even if its clearance from the brain is sluggish. It has been suggested earlier that the proximity of cardiovascular regulatory centers to the CSF may allow one to regard the CSF NE content as an index of noradrenergic neurotransmission in this area (Eide et aL, 1979). We have confirmed the correlation between CSF and plasma free NE previously observed (Ziegler et aL, 1977).…”

“…The additional positive relationship between CSF and plasma free E, HVA and particularly NE and DA sulfates found in this study may point to a unidirectional movement of some free and sulfated CA and HVA from the brain to the blood. Very recent data suggesting that CSF DA sulfate may originate in the caudate nucleus of monkeys (Elchisak et al, 1983) open the possibility that the CSF determination of CA sulfates may offer an insight into the CA events in the brain which are only partly reflected by measurements of free CA (Eide et aL, 1979). This may be particularly useful in hypertension research.…”

Decreased pituitary response to insulin-induced hypoglycaemia in young lean male patients with essential hypertension

“…Increased baseline norepinephrine concentrations observed in HT subjects could reflect the increased norepinephrine levels in cerebrospinal fluid. [35][36][37] The elevated norepinephrine levels in cerebrospinal fluid and in the internal jugular venous overflow from subcortical brain regions 38,39 may cause an alteration in noradrenergic receptors in several brain structures, including those responsible for release of pituitary hormones. It has been proposed that HT patients may have altered sensitivity of central alpha-adrenergic receptors on associated hypothalamic neurons.…”

The sympathetic nervous system: the muse of primary hypertension

“…14 On the other hand, in patients with phenochromocytoma the levels of CA were much lower in the spinal fluid than they were in the plasma. Thus there appeared to be no penetration of the blood brain barrier by the CA in the blood of the patients with pheochromocytoma.…”