الفهرس 
Material and methodsOnly 14 pages are availabe for public view
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Abstract
Abnormalities of Calcium metabolism have been described in
patients with essential hypertension. The role of calcium in the regulation
of blood pressure is receiving increased attention
The aim of this work is to study calcium homeostasis in essential
hypertensive patients to shed light on the mechanisms played by
calciotropic hormones in the pathogenesis of essential hypertension.
Thirty essential hypertensive patients as well as ten well matched healthy
volunteers as control had been selected for this study.
Diagnosis of secondary hypertension was adequately excluded by
meticulous history and clinical examination and by the finding of normal
urine analysis, serum creatinine and serum electrolytes, and by radiologic
studies, and electrocardiography (BCG), when clinically indicated.
Patients taking contraceptive pills, or injections, glucocorticoids,
phosphate binding antacids, sex hormones or those on weight reducing
diets, or pregnant were excluded from the study.
Patients and controls were subjected to full medical history and
examination and the following investigations were done:
1-·Serum creatinine.
2-Serum sodium and potassium
3-serum calcium, 1.25 (OH)2D and Parathyroid hormone (PTH).
4-Plasma renin activity (PRA).
5-24 hours urinary calcium.
The results of this work showed:
I-No significant difference between the mean serum calcium values in
the hypertensive group and the control group.
2-Significant elevation of the mean value of 24 hours urinary calcium in
the hypertensive group when compared to the control group, with
hypercalciuria in 70% of patients.
3-Significant elevation of the mean value of serum 1,25 (OH)2D in the
hypertensive group when compared to the control group with elevated
serum 1,25(OH)2Din 40% of patients.
4-Significant elevation of the mean value of serum PTH in the
hypertensive group when compared to the control group, with
elevated serum PTH in 60% of patients.
5-No correlation was observed among serum PTH, serum 1,25 (OH)2
D
and urinary calcium in the hypertenisve group.
from this study, we come to the conclusion that:
_Hypercalciuria is a major derangement of calcium metabolism in
patients with essential hypertension. This may be due to a defective
renal tubular calcium transport.
-The elevated PTH and 1,25 (OH)2D in essential hypertension might be a
compensatory response in trial to restore calcium balance to normal.
-These calciotropic hormones directly facilitate calcium transport from
the extracellular space in the cell resulting in intracellular calcium
accumulation and increase in cytosolic free ca’” concentration found
in patients with essential hypertension. The cytosolic free calcium
concentration is crucial for the vascular contractile activity and hence,
elevation in blood pressure.
Further research is recommended to study the association among
systemic markers of calcium metabolism, cellular calcium metabolism
and arterial blood pressure regulation.