Biological activity of endogenous and exogenous calcitonin in patients with osteitis fibrosa and chronic renal failure.

Successful treatment of osteitis fibrosa with 1alpha-hydroxycholecalciferol (1alpha-OHD3) in 9 patients with end-stage chronic renal failure was associated with a significant increase in plasma levels of immunoreactive calcitonin (iCT) independently of changes in plasma calcium, and a decrease in levels of parathyroid hormone (iPTH). In 9 further patients whose plasma alkaline phosphatase activity failed to suppress with 1alpha-OHD3, changes in iPTH were associated with proportionate changes in iCT. This suggests that a rise in endogenous calcitonin (CT) secretion contributes to the success of treatment with 1alpha-OHD3.

Correlation of clinical, biochemical and skeletal responses to 1alpha-hydroxyvitamin D3 in renal bone disease.

Thirty-five patients with bone disease and chronic renal failure (twenty-four on maintenance haemodialysis) were treated for 7--39 months with 1alpha-hydroxyvitamin D3, 2--2.5 microgram daily by mouth. Symptoms (bone pain and muscle weakness) and radiographic appearances improved and plasma alkaline phosphatase returned to normal in the majority of patients (87, 76 and 75% respectively).

Effects of analgesics and related compounds on renal metabolism in rats.

1. The metabolic effects of p-aminophenol have been compared with those of paracetamol and other analgesics in studies of rat liver and kidney in vitro. 2.

Plasma catecholamines and the pressor response to Sar1-Ala8-angiotensin II in man.

1. The initial blood pressure response to saralasin (Sar1-Ala8-angiotensin II) infusion was examined in 15 normal subjects, eight patients with untreated essential hypertension and 65 patients established on chronic haemogialysis (including six anephric patients), and related to measurements of plasma renin activity (PRA), angiotensin II, plasma catecholamines (noradrenaline and adrenaline), blood volume and extracellular fluid volume ([35S]sulphate space or exchangeable sodium). 2.

The effect of dietary sodium intake on the blood pressure and cardiac output responses to angiotensin II in unanaesthetized rats.

1. Dose-response curves for the pressor activity of angiotensin II have been determined in unanaesthetized rats receiving diets containing 2-5% (w/w) or 0-007% (w/w) sodium and administered in various sequences. 2.

Renal osteodystrophy in nondialysed adolescents. Long-term treatment with 1alpha-hydroxycholecalciferol.

The effects of small oral doses (1-2 microgram/day) of 1alpha-hydroxycholecalciferol, given for 1 to 2 years, have been examined in four nondialysed adolescents with chronic renal failure and bone disease. Treatment increased calcium retention and plasma calcium, and decreased plasma levels of alkaline phosphatase, hydroxyproline, and immunoreactive parathyroid hormone. X-ray abnormalities of bone regressed, and 2 patients underwent successful surgical correction of knock-knees; bone histology in these 2 was normal at the time of operation.

Changes in histologic and biochemical indexes of bone turnover after bilateral nephrectomy in patients on hemodialysis. Evidence for a possible role of endogenous calcitonin.

We studied the effects of bilateral nephrectomy on bone metabolism in 27 patients on maintenance hemodialysis. After nephrectomy plasma alkaline phosphatase fell rapidly in 10 patients whose preoperative plasma levels had been higher than normal. This fall was associated with a transient decrease in osteoblast counts of iliac-bone biopsies.

The role of the kidney in hypertension.

The role of the kidney in hypertension is reviewed in terms of sodium and water homeostasis, of the secretion of renin inappropriate to the state of sodium and water balance and of other renal humoral factors which might be implicated in the hypertensive process. Fundamental to the long-term maintenance of hypertension is an alteration in the relationship between renal perfusion pressure and the excretion of sodium and water. This alteration may be brought about as a result of renal structural damage, sympathetically mediated renal vasoconstriction or the action of renal or extrarenal hormones which modulate sodium and water excretion.

Evidence that endogenous calcitonin protects against renal bone disease.

Plasma concentrations of calcium, phosphate, alkaline phosphatase (A.P.), immunoreactive calcitonin (iC.

Reduced plasma renin activity in essential hypertension: effects of blood pressure, age and sodium.

1. Supine plasma renin activity and its responsiveness to erect posture and frusemide were reduced in fifty-one patients with essential hypertension, compared with fifty-one age- and sex-matched control subjects. 2.

Renin unresponsiveness and the effects of oxprenolol, methyldopa and spironolactone in pateints with essential hypertension.

Plasma renin activity (PRA), supine, erect and post-frusemide (1 mg/kg IV) was studied in 51 patients with previously untreated essential hypertension and their age- and sex-matched normotensive controls. Supine PRA, and the rise in PRA in response to the erect posture and frusemide, were significantly less in hypertensives compared to controls. When the hypertensives were arbitrarily divided into lower, mid, and upper subgroups according to supine PRA, the renin responsiveness was similar in each subgroup but significantly less in hypertensives compared to controls, subdivided in the same way.

The influence of sodium intake on the pressor response to angiotensin II in the unanaesthetized rat.

1. Dose-response curves for the pressor activity of angiotensin II have been determined in unanaesthetized rats receiving diets containing 2-5% (w/w) or 0-007% (w/w) sodium; the different diets were administered in various sequences. 2.

Experimental renal hypertension.

The study of hypertension resulting from procedures devised to modify renal function in diverse ways has been pursued intensively in the past forty years and has contributed greatly to the understanding of hypertensive processes in man. Such procedures have included partial or complete removal of renal tissue, interference with the renal circulation and the administration of sodium and hormones promoting the tubular reabsorption of sodium. From all these studies, certain basic conclusions can be drawn.

Effects of beta-adrenergic receptor blockade on the renal vascular response to a low sodium diet in the rabbit.

1. The effect of propranolol on total and regional renal blood flow was measured in conscious rabbits after 6 days on normal or low sodium diets. 2.

Urinary tract in schoolgirls with covert bacteriuria.

During screening of 16,800 primary schoolgirls, aged 4-12 years, in Cardiff and Oxford, significant bacteriuria was found in 294 (1-7%). Intravenous urography and micturating cystography were performed in 246 of these girls. The urinary tract was abnormal in 47%.