Plasma concentrations of adrenomedullin and atrial and brain natriuretic peptides in patients with adrenal pheochromocytoma

Abstract

The present study aimed to evaluate any changes in the plasma concentrations of adrenomedullin (ADM), atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) in patients with adrenal pheochromocytoma (PC). The plasma concentrations of the three peptides were measured in 45 healthy control individuals and 90 untreated patients with PC, who consisted of 20 normotensive patients, 30 borderline hypertensive patients and 40 hypertensive patients. After 4 weeks of effective antihypertensive therapy for hypertensive PC patients, the concentrations of ADM, ANP and BNP were measured again, and laparoscopic adrenalectomy was then performed for all PC patients with values that were measured 2 weeks later. The plasma concentrations of the three peptides were significantly increased in the borderline hypertensive and hypertensive patients compared with the concentrations in control individuals and normotensive patients. In addition, there were significant differences between the levels of ADM, ANP and BNP in the borderline and hypertensive groups. The plasma ADM concentration was not associated with the blood urea nitrogen levels, serum creatinine levels or glomerular filtration rate, but was correlated with the serum epinephrine, serum norepinephrine and urine vanillylmandelic acid levels. In addition, the ADM concentration was associated with the systolic blood pressure, diastolic blood pressure, left ventricular ejection fraction, left ventricular mass index and plasma concentrations of ANP and BNP in the hypertensive patients with PC. After 4 weeks of antihypertensive treatment, the values of the three peptides in the hypertensive patients with PC were not significantly changed. As expected, the values in borderline and hypertensive groups were significantly decreased 2 weeks subsequent to surgery, whereas there were no significant changes in the normotensive group. ADM may participate, along with ANP and BNP, in the mechanisms that counteract further elevation of blood pressure in patients with PC, and there may be an ADM/catecholamine local regulatory mechanism that is important for the control of adrenal medulla functions.

Keywords: adrenal; adrenomedullin; atrial natriuretic peptide; brain natriuretic peptide; pheochromocytoma.

Figure 1.

Plasma concentrations of ADM, ANP and BNP in the control and three PC subgroups. PC, pheochromocytoma; ADM, adrenomedullin; ANP, atrial natriuretic peptide; BNP, brain natriuretic peptide.

Figure 2.

Association between the plasma ADM concentrations and (A) BUN, (B) Scr, (C) GFR, (D) serum E, (E) serum NE and urine (F) VMA in hypertensive patients with pheochromocytoma. BUN, blood urea nitrogen; Scr, serum creatinine; GFR, glomerular filtration rate; E, epinephrine; NE, norepinephrine; VMA, vanillylmandelic acid; ADM, adrenomedullin.

Figure 3.

Association between the plasma ADM concentrations and (A) SBP, (B) DBP, (C) LVEF, (D) LVMI, (E) ANP and (F) BNP levels in hypertensive patients with pheochromocytoma. SBP, systolic blood pressure; DBP, diastolic blood pressure; LVEF, left ventricular ejection fraction; LVMI, left ventricular mass index; ADM, adrenomedullin; ANP, atrial natriuretic peptide; BNP, brain natriuretic peptide.

Figure 4.

The plasma concentrations of ADM, ANP, and BNP initially, 4 weeks after effective antihypertensive therapy and 2 weeks after surgery in hypertensive patients with pheochromocytoma. ADM, adrenomedullin; ANP, atrial natriuretic peptide; BNP, brain natriuretic peptide.