Elevated angiotensin II and vasopressin in primary hyperparathyroidism. Angiotensin II infusion studies before and after removal of the parathyroid adenoma

Abstract

In order to evaluate the role of calcium metabolism in blood pressure regulation, 15 patients with primary hyperparathyroidism and 9 healthy control subjects were studied before and during angiotensin II infusion. The patients were re-investigated 2\p=n-\5months after removal of the parathyroid adenoma. Blood pressure, plasma levels of angiotensin II, aldosterone, arginine vasopressin, and atrial natriuretic peptide, and creatinine clearance were determined. Blood pressure and the blood pressure response to angiotensin II infusion were both the same before and after the operation. Angiotensin II and arginine vasopressin during basal conditions were significantly higher before than after the operation (angiotensin II: 17 (median) to 10 pmol/l, P < 0.02; arginine vasopressin: 2.9 to 1.9 pmol/l, P < 0.01), whereas aldosterone, atrial natriuretic peptide, and creatinine clearance were unchanged. During angiotensin II infusion, aldosterone, arginine vasopressin, and atrial natriuretic peptide increased to approximately the same levels before and after the operation. Blood pressure was not correlated to any of the hormones measured. Thus, patients with primary hyperparathyroidism have elevated plasma levels of angiotensin II and arginine vasopressin which may be compensatory phenomena counteracting volume depletion owing to a decreased renal concentrating ability induced by hypercalcemia, and owing to PTH-induced inhibition of renal sodium reabsorption.

Furosemide stimulation of parathormone in humans: role of the calcium-sensing receptor and the renin-angiotensin system

“…Indeed, calcium sensing receptors are expressed in juxtaglomerular cells in mice [23] and rats [18]. Recent findings in humans indicate that there is a tight link between the RAAS and the parathyroid glands, suggesting that the RAAS may mediate the furosemide effect on PTH secretion [4,15,16,19,20,22,29]. In a previous experimental study, we demonstrated that administration of the calcimimetic RS568 inhibited renin secretion in rats and blunted the renin response induced by furosemide [18].…”

Effects of treatment with an angiotensin 2 receptor blocker and/or vitamin D3 on parathyroid hormone and aldosterone: A randomized, placebo‐controlled trial

“…Most studies investigating the link between the RAAS and the calcium homeostasis have in fact not considered this issue. Infusions with angiotensin 2 and aldosterone have not been reported to increase renal calcium or magnesium excretion, questioning whether the hypothesized association is due to reduced blood pressure levels per se rather than a real association between the hormone axes …”

“…Infusions with angiotensin 2 and aldosterone have not been reported to increase renal calcium or magnesium excretion, questioning whether the hypothesized association is due to reduced blood pressure levels per se rather than a real association between the hormone axes. 23,24 In the EPATH trial, there was a trend (P = .10) towards a decreased 24-hour renal calcium excretion in response to treatment with eplerenone. 16 In accordance with other studies, we found that levels of ionized calcium and 24 hours renal calcium excretion correlated positively to SBP and DBP.…”

Epidemiology, Pathophysiology, and Genetics of Primary Hyperparathyroidism

“…(97,98) Some investigators have found elevated plasma levels of angiotensin in patients with PHPT. (99) However earlier work found no effect of parathyroidectomy on the plasma renin activiy (PRA) axis in patients with PHPT. (100,101) Further, elevated levels of 1,25vitamin D often seen in PHPT would, based on recent data, suppress the PRA axis.…”