Plasma renin concentration in human hypertension . II. Renin in relation to aetiology.

Abstract

In previous papers (Brown et al., 1965a(Brown et al., , 1965b we have demonstrated, in clinical hypertension, a close inverse relationship between renin concentration and plasma sodium which appears to be independent of aetiology, the height of the arterial pressure, complications, and treatment. The present communication is concerned with an analysis of renin and sodium in hypertension in relation to aetiology. The methods used in this study are as given previously (Brown et al., 1965b(Brown et al., , 1965d; data on additional cases have been included, but the series is basically that described earlier. Plasma In this condition hypertension is caused by an aldosteronesecreting adrenal cortical adenoma (Conn, 1955;Mader and Iseri, 1955 ;Milne et al., 1957;Conn et al., 1964b). Plasma sodium and total exchangeable sodium are often raised, while potassium is low. Whether all the features of the syndrome can be attributed solely to the excess aldosterone, or whether other hormones produced by the tumour are necessary, has been the subject of discussion (see Ross and Hurst, 1965).The hypertension and increased exchangeable sodium are accompained by depression of plasma renin concentration ; after removal of the tumour, with correction of the hypertension and electrolyte abnormalities, renin rises into the normal range (Brown et al., 1963b(Brown et al., , 1964a(Brown et al., -c, 1965d (Fig. 1).Alternatively, the administration of spironolactone to patients with this syndrome may correct the hypertension and electrolytes without affecting aldosterone secretion (Brown et al., 1963b(Brown et al., , 1964a(Brown et al., , 1964b(Brown et al., , 1964c(Brown et al., , 1965d; plasma renin concentration rises to normal as the sodium falls, emphasizing the interrelationship between renin and sodium, and showing that the effect of the adrenal overactivity on renin concentration is not a direct one but is mediated by the electrolyte abnormalities (Brown et al., 1963b(Brown et al., , 1964a(Brown et al., , 1964c operation in a patient with primary aldosteronism, the values rising after removal of the tumour. Findings similar to those of Kirkendall et al. (1964), but with an occasional result well in the measurable range before operation, were later published by Conn et al. (1964a), who used the extraction procedure of Boucher et al. (1964

Circadian Variations of Plasma Renin Activity and Plasma Osmolality in Various Physiological and Pathological States

“…There was a significant reciprocal correla tion between these values. This finding may be comparable to the reports that PRA values are inversely correlated to the sodium concentration in plasma (Brown et al 1965), since plasma osmolality is largely dependent upon the concentration of plasma sodium. These results may also support the concept that RA-system is closely related to the physiological control of the homeostasis in body fluid and electrolyte.…”

Pathophysiology of renovascular hypertension.

“…101 Although PRA may be normal in humans with long-standing, predominantly unilateral renovascular hypertension, its level is never low nor does it closely correlate with the degree of blood pressure elevation. 102 Yet hypertension will respond to converting enzyme inhibition in this stage. 103 The possibility must be considered that local renin-angiotensin action, rather than the circulating concentrations of these substances, is what determines the level of blood pressure and organ damage.…”

Post-Hydralazine Renin Release in the Diagnosis of Renovascular Hypertension

“…For this reason, investigators have recently become interested in the renin levels of peripheral blood, or in blood samples taken directly from renal veins for preoperative diagnosis of renovascular hypertension.1 2,5,6,7,13,14 Experience has indicated that this method also may frequently lead to misdiagnosis because of false positive and false negative results.2 5,13,15 Consequently, we began, 4 years ago, to measure renal venous renin levels after hydralazine infusion to improve the diagnostic …”