PubMed Health⌕ Search

Biomedical subjects

J de Graeff

Publications and source records attributed to J de Graeff.

At least 37 records · Page 2Linked to original sources
PubMed1978

Influence of sodium intake on hydrochlorothiazide-induced changes in blood pressure, serum electrolytes, renin and aldosterone in essential hypertension.

To determine the influence of dietary sodium intake on the effects of hydrochlorothiazide (HCT) on blood pressure (BP), serum electrolytes, renin and aldosterone, nine male patients with uncomplicated essential hypertension were studied during the following therapeutic regimes: 1) sodium restriction alone (50 mmol/day), 2) sodium restriction combined with HCT (50 MG TWICE DAILY), 3) HCT alone, and 4) sodium restriction combined with HCT. Low sodium diet alone and HCT alone lowered BP to the same extent. The combination of HCT and sodium restriction had no extra effect on supine BP, but elicited complaints of dizziness and weakness in each patient, and overt orthostatic hypotension in three cases. Sodium restriction during HCT treatment caused hyponatraemia and aggravated hypokalaemia. Hyponatraemia could not be accounted for solely by changes in cumulative sodium balance. Plasma renin concentration rose markedly during the combined treatment. Plasma aldosterone was normal during HCT alone, but elevated when HCT was combined with sodium restriction. These results cast some doubt on the therapeutic value of prescribing a low sodium diet to patients with essential hypertension treated with thiazide diuretics. Overactivity of the renin-angiotensin-aldosterone system during this regime might explain both the lack of a beneficial effect on BP and the adverse influence on serum potassium.

Adult↗
PubMed1978

Synthesis and degradation of glomerular basement membrane in rats with nephrotoxic nephritis.

Degradation and synthesis of the collagen portion (CLP) of the glomerular basement membrane (GBM) in glomeruli of rats with nephrotoxic nephritis (NTN) were determined in vivo and in vitro. Degradation of CLP in rats with NTN was only increased during the first 24 h after induction of NTN. After 24 h, the half-life of CLP in NTN rats (16.9 days) was not significantly different from that in the controls 15.6 days). The loss of CLP during the first 24 h is accompanied by an increased synthesis, measured in vivo and in vitro. The increased synthesis, however, does not seem to be sufficiently high to result in accumulation of CLP-like material in NTN. Since degradation and synthesis of CLP was not altered during the later phase of NTN, it is unlikely that chronic proteinuria is the result of an ongoing abnormal turnover of CLP.

Animals↗
PubMed1978

Bone scintigraphy in renal osteodystrophy.

Bone scintigraphy with Tc-99m HEDP was performed in 30 patients on maintenance hemodialysis, and the results of quantitative analysis were compared with those of a normal group. To permit this comparison, elevated background activity due to the absence of renal radiotracer excretion was reduced by hemodialysis to levels found in the normals. Histologic proof of renal osteodystrophy had been obtained in all patients. The incidence of radiographic abnormalities was 46%, whereas abnormal scans were found in 25 patients (83%); skeletal lesions were also more pronounced and detected earlier. However, even when the scans appeared normal, the quantitative analysis showed increased skeletal activity in all patients. The total skeletal activity proved to be a good index of the severity of renal osteodystrophy and appeared dependent on both osteomalacia and hyperparathyroidism. These findings show that bone scintigraphy is a sensitive method to detect skeletal involvement in renal osteodystrophy.

Adolescent↗
PubMed1977

Effect of indomethacin on the synthesis of glomerular basement membrane and on proteinuria in rats with nephrotoxic nephritis.

The effect of indomethacin on protein excretion and on the synthesis of glomerular basement membrane (GBM) was studied during various stages of nephrotoxic nephritis (NTN) in the rat. Daily administration of indomethacin (4 mg/kg) was instituted 1, 6, or 21 days after the induction of NTN with 210, 240, or 268 microgram kidney-fixing antibodies (KFAb). Proteinuria in rats with nephritis induced by 210 microgram KFAb decreased under treatment with indomethacin regardless of the day on which treatment was started but was not affected by indomethacin in rats with clinically more severe nephritis induced with higher doses of KFAb. GBM synthesis was measured in vivo and in vitro by determination of the incorporation of 3H-proline into the GBM. NTN rats treated with indomethacin showed increased GBM synthesis early in the course of NTN, over and above an already increased synthesis. In the later phase of NTN indomethacin treatment did not affect GBM synthesis. The absence of a relationship between the effect of indomethacin on proteinuria and its effect on GBM synthesis clearly shows that the reduction of protein excretion occurring under indomethacin treatment is not mediated by alterations in the rate of GBM synthesis.

Animals↗
PubMed1976

Unilateral renal vein thrombosis and nephrotic syndrome. Report of a case with protein selectivity and antithrombin III clearance studies.

A case of the nephrotic syndrome with unilateral renal vein thrombosis is reported. The patient, an 18 year old man, presented with a six month history of edema and the recent development of a left-sided varicocele. An enlarged left kidney and a thrombus in the left renal vein were demonstrated roentgenographically. A biopsy specimen of the right kidney was interpreted as membranous glomerulonephritis. Selective renal function studies showed nearly identical creatinine excretion, and similar total protein excretion and protein selectivity from each kidney. Thus, the thrombus in the left renal vein did not influence glomerular filtration rate or quantitative or qualitative protein excretion. A high urinary output and a decreased serum level of antithrombin III were measured. These findings suggest a mechanism to explain the increased thrombotic tendency seen in this and other patients with the nephrotic syndrome.

Adolescent↗