TY - JOUR
T1 - Regulation of parathyroid hormone and vitamin D in essential hypertension
AU - Young, Eric W.
AU - Morris, Cynthia D.
AU - Holcomb, Scott
AU - McMillan, Grace
AU - McCarron, David A.
N1 - Funding Information:
Received November 17, 1994. Accepted May 8, 1995. uman essential hypertension has been as-From the Division of Nephrology, Hypertension, and Clinical sociated with alterations of systemic cal-Pharmacology, Oregon Health Sciences University,, Portland, Or- cium metabolism. Several links between University of Michigan, Ann Arbor, Michigan (EWY). egon (CDM, SH, GMM, DAMC), and Division of Nephrology, H calcium metabolism and blood pressure Supported in part by a General Clinical Research Center Grant control have been hypothesized, such as common (RR0034-2152) from the National Institutes of Health, a Clinical (5M01 RR00334-21) and a Clinical Associate Physician Award cellular transport systems or direct vascular actions of Nutrition Research Unit Grant from the National Institutes of Di- calcium and calcium-regulating hormones. When gestive, Diabetes and Kidney Diseases (T30 DK40566), and a grant compared to normotensive controls, patients with es-Address correspondence and reprint requests to Eric W. Young, from the National Dairy Council. sential hypertension have been reported to have de-MD, Nephrology Section (111-J), VA Medical Center, 2215 Fuller creased serum ionized calcium concentration, 1-5 hy-Road, Ann Arbor, MI 48105. percalciuria, 4-7 elevated serum parathyroid hormone
PY - 1995/10
Y1 - 1995/10
N2 - Patients with essential hypertension have been reported to have a higher serum concentration of parathyroid hormone (PTH) than normotensive individuals although this finding is not universal among studies. To further characterize the status of the calcium regulating hormones in essential hypertension, we measured the parathyroid gland response to acute EDTA-induced hypocalcemia and the renal response of 1,25(OH)2-vitamin D to dietary calcium deprivation in 16 hypertensive (H) and 15 normotensive (N) men. The average mean arterial blood pressure once all antihypertensive medications were discontinued was 108 ± 7 mm Hg for the hypertensive group and 89 ± 4 mm Hg for the normotensive group (P < .01). There were no group differences in baseline serum concentrations of ionized calcium, creatinine, intact PTH, and 1,25(OH)2-vitamin D, urinary calcium excretion, and creatinine clearance. After a 1-h infusion of EDTA at 12.5 mg/kg/h, the serum concentration of ionized calcium fell (H: 1.25 ± .03 to 1.17 ± .04 mmol/L, N: 1.26 ± .04 to 1.18 ± .04 mmol/L, P = NS) and PTH increased (H: 36 ± 9 to 91 ± 30 pg/ mL, N: 40 ± 14 to 85 ± 28 pg/mL, P = NS). With an additional hour of EDTA at a dose of 25 mg/kg/h, serum ionized calcium concentration fell further (H: 1.01 ± .05 mmol/L, N: 1.03 ± .06 mmol/L, P = NS) and PTH increased to 150 ± 58 pg/mL in patients and 130 ± 32 pg/mL in controls (P < .001). The response suggested an increased maximal parathyroid gland secretory capacity in the hypertensive patients relative to the controls. There was no group difference in the serum concentration of 1,25(OH)2-vitamin D at baseline (H: 32 ± 6 pg/mL, N: 32 ± 8 pg/mL, P < .90) and following dietary calcium deprivation for three days (H 50 ± 12, N 48 ± 14 P < 0.76). The maximal stimulated PTH level was significantly higher in hypertensive than normotensive subjects in the absence of measured differences in serum ionized calcium concentration, serum 1,25(OH)2-vitamin D concentration, and creatinine clearance. These findings suggest an intrinsic alteration of PTH regulation in patients with essential hypertension, manifest as increased parathyroid gland secretory capacity.
AB - Patients with essential hypertension have been reported to have a higher serum concentration of parathyroid hormone (PTH) than normotensive individuals although this finding is not universal among studies. To further characterize the status of the calcium regulating hormones in essential hypertension, we measured the parathyroid gland response to acute EDTA-induced hypocalcemia and the renal response of 1,25(OH)2-vitamin D to dietary calcium deprivation in 16 hypertensive (H) and 15 normotensive (N) men. The average mean arterial blood pressure once all antihypertensive medications were discontinued was 108 ± 7 mm Hg for the hypertensive group and 89 ± 4 mm Hg for the normotensive group (P < .01). There were no group differences in baseline serum concentrations of ionized calcium, creatinine, intact PTH, and 1,25(OH)2-vitamin D, urinary calcium excretion, and creatinine clearance. After a 1-h infusion of EDTA at 12.5 mg/kg/h, the serum concentration of ionized calcium fell (H: 1.25 ± .03 to 1.17 ± .04 mmol/L, N: 1.26 ± .04 to 1.18 ± .04 mmol/L, P = NS) and PTH increased (H: 36 ± 9 to 91 ± 30 pg/ mL, N: 40 ± 14 to 85 ± 28 pg/mL, P = NS). With an additional hour of EDTA at a dose of 25 mg/kg/h, serum ionized calcium concentration fell further (H: 1.01 ± .05 mmol/L, N: 1.03 ± .06 mmol/L, P = NS) and PTH increased to 150 ± 58 pg/mL in patients and 130 ± 32 pg/mL in controls (P < .001). The response suggested an increased maximal parathyroid gland secretory capacity in the hypertensive patients relative to the controls. There was no group difference in the serum concentration of 1,25(OH)2-vitamin D at baseline (H: 32 ± 6 pg/mL, N: 32 ± 8 pg/mL, P < .90) and following dietary calcium deprivation for three days (H 50 ± 12, N 48 ± 14 P < 0.76). The maximal stimulated PTH level was significantly higher in hypertensive than normotensive subjects in the absence of measured differences in serum ionized calcium concentration, serum 1,25(OH)2-vitamin D concentration, and creatinine clearance. These findings suggest an intrinsic alteration of PTH regulation in patients with essential hypertension, manifest as increased parathyroid gland secretory capacity.
KW - Parathyroid hormone
KW - calcium
KW - essential hypertension
KW - vitamin D
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U2 - 10.1016/0895-7061(95)00214-6
DO - 10.1016/0895-7061(95)00214-6
M3 - Article
C2 - 8845076
AN - SCOPUS:0028791086
SN - 0895-7061
VL - 8
SP - 957
EP - 964
JO - American Journal of Hypertension
JF - American Journal of Hypertension
IS - 10
ER -