摘要:

Inulin and mannitol clearances, BUN concentrations and renal morphologic alterations were studied in rats 24 h after the injection of low doses of mercuric chloride. Water drinking rats given 4.7 mg/kg body weight of HgCl2 developed renal failure and severe tubular necrosis. Their clearance of inulin was decreased to the same degree as their simultaneously determined mannitol clearance. Any significant change in tubular permeability should have resulted in a greater loss of mannitol than inulin, and it is suggested that tubular permeability to neither molecule was greatly increased. This is supported by the fact that rats drinking one percent saline in place of tap water for a month prior to receiving the same dose of HgCl2 showed insignificant changes in inulin clearance and minimal elevations in BUN concentration. Nevertheless, histologic sections of their kidneys showed frank tubular necrosis that was equally severe as, but slightly less extensive than that observed in the water drinking rats whose inulin clearance was 6 % of normal. In view of these findings, it seems unlikely that alterationin tubular permeability per se are responsible for the development of acute renal failure in low dose mercury poisoning. The protective effect of salt loading does not depend on the prevention of tubular injury, and may well reflect inhibition of pre-glomerular vasoconstriction by suppression of the renin-angiotensin axis.

ISSN:1660-8151    

DOI:10.1159/000179922

出版商:S. Karger AG    

年代:1971

数据来源: Karger

摘要:

One day after rats were injected with 4.7 mg/kg HgCl2 subcutaneously, their surface nephrons usually were fluid filled, had a normal intratubular pressure, but formed minimal volumes of filtrate. Proximal tubule fluid flow rate was greatly diminished, material resembling cell debris obstructing the outflow of fluid. The finding of normal, rather than elevated, intratubular pressure in obstructed tubules indicates that effective filtration pressure probably was grossly reduced. Fluid absorption in the proximal tubule appeared to be greatly impaired. Despite slow flow in the undisturbed nephron, fluid could be collected from the proximal tubule at a normal rate, single nephron GFR being some 80% of control. The return of filtration on ‘venting’ the nephron during collections, and sustained normal single nephron GFR values after obstruction was relieved by washout of debris suggest a feed-back mechanism between impairment of tubular flow and intraglomerular filtration pressure. Intravenously injected lissamine green appeared promptly in distal tubule segments after release of obstruction, confirming the return of a normal proximal tubule fluid flow rate. Evidence for pathologically increased absorption of filtrate was not found. It is concluded that effective filtration pressure is significantly reduced in acute renal failure produced in the rat with low doses of HgCl2 that tubular obstruction plays a role in the maintenance of the low filtration pressure, and that the discrepancy between whole kidney and single nephron inulin clearance values is artifactual. The latter features appear to be unique to low dose mercury poisoning and differ significantly from findings in other models of experimental acute renal failure in the

ISSN:1660-8151    

DOI:10.1159/000179923

出版商:S. Karger AG    

年代:1971

数据来源: Karger

摘要:

A number of renal function tests were combined into one 7-hour day in the rat, using urinary tests only to allow sequential measurements in individual animals, and involving 18 measurements for each one-day test. The use of 1.42% sterile sodium sulphate solution containing 3 mg% phenolsulphonphthalein (20 ml/kg) and a mineralocorticoid drug (Florinef, 9-α-fluorohydrocortisone, 0.2 mg/kg) by intraperitoneal injection was found to overcome the difficulty of achieving reproducible values for minimum urinary pH in the rat. Pitressin (antidiuretic hormone) was observed to interfere with minimum urinary pH, and its administration (0.4 units/kg i.p.) was delayed for 2 h. Normal values (mean ± SD) obtained in 64 one-day tests in 40 animals (involving over 1,000 measurements) were as follows: urinary protein (Albustix), 30 ± 15mg%; urinary phenolsulphonphthalein excretion in first hour, 27 ± 5 (males) and 37 ± 7 (females), as percent of injected dose; maximum sodium excretion after sodium load, 1,300 (range 700–2,200) µEq/mg creatinine; minimum sodium excretion after mineralocorticoid load, 10 ± 7 µEq/mg creatinine; maximum sodium excretion/conservation ratio 130 (range 40–1,100); maximum urinary creatinine concentration after Pitressin, 150 ± 35 mg%; and minimum urinary pH in second hour after sulphate load, 5.1 ± 0.2 units. In a 6-week illustrative study of cases of acute experimentally-induced renal disease, the administration of analgesic powders (42% aspirin, 42% phenacetin and 16% caffeine citrate) to 2 cases (8 one-day tests) or acetazoleamide to 3 cases (9 one-day tests) was found to induce defects in urinary concentrating ability after Pitressin and in minimum sodium excretion after a mineralocorticoid load, suggesting specific tubular or vasa recta lesions. Analgesic powders possibly affected the urinary acidification mechanism as well. On the other hand, dosage with puromycin aminonucleoside or human serum albumin in 4 cases (16 one-day tests) produced mainly decreased glomerular function and proteinuria typical of the nephrotic syndrome, with decreased flexibility of urinary sod

ISSN:1660-8151    

DOI:10.1159/000179924

出版商:S. Karger AG    

年代:1971

数据来源: Karger

摘要:

Sucrose-14C was administered to rats in solutions of 12.5 and 50%. Radioactivity was found in renal cortical cells and was partly sedimentable on centrifugation of homogenates. Over a 24-hour period, there was a sharp decrease in the amount of non-sedimentable radioactivity whereas no net change in sedimentable radioactivity occurred during this period. Utilizing isopycnic density gradient centrifugation, it was found that part of the sedimentable radioactivity distributed with lysosomal acid phosphatase. These findings, in conjunction with histochemical data of others, suggest that sucrose-induced vacuolization of renal cortical cells is a reflection of the incorporation of sucrose into phagolysosomes. Since this process is most likely mediated through pinocytosis and not by osmotic changes, the term ‘osmotic nephrosis’ appears to be inappropriate when applied to describe the etiology of sucrose nephro

ISSN:1660-8151    

DOI:10.1159/000179925

出版商:S. Karger AG    

年代:1971

数据来源: Karger

摘要:

Six of 27 patients with nephrotic syndrome excreted α2-macroglobulin in the urine. In the presence of this protein the glomerular selectivity determination by means of immunoglobulin G and transferrin alone gives values which differ from selectivity determinations which include α2-macroglobulin. The inclusion of α2-macroglobulin in these calculations is suggested because it provides a better reflection of glomerular permeability to high molecular weight protei

ISSN:1660-8151    

DOI:10.1159/000179926

出版商:S. Karger AG    

年代:1971

数据来源: Karger

摘要:

Previously reported results for exchangeable potassium in advanced renal failure have been conflicting. We have studied, therefore, 13 patients in advanced chronic renal failure with a mean urea clearance of 3 ml/min and a mean creatinine clearance of 4.1 ml/min, and without evidence of unusual extrarenal potassium losses. The results of exchangeable potassium in both males and females were not significantly different from normal (43.3 mEq/kg in males and 35.9 mEq/ kg in females). In the majority of patients overall potassium secretion was observed. Our results do not support arbitrary potassium supplementation in patients treated conservatively for renal failure in an effort to improve their glucose tolerance.

ISSN:1660-8151    

DOI:10.1159/000179927

出版商:S. Karger AG    

年代:1971

数据来源: Karger

摘要:

Serum-alkaline phosphatase in man is mainly derived from bone or liver. It has been confirmed that alkaline phosphatase of skeletal origin is heat-labile. Normal individuals have mean heat-stable values of 30.7%. In children, healing fractures, and patients with osteitis fibrosa the alkaline phosphatase of bone origin is increased, and in these groups the mean thermostable values were 9.6, 21.8 and 18.7%, respectively. In these cases the decrease in thermostable values appear to be diagnostic even in the presence of a normal total alkaline-phosphatase value. From this study, thermostable alkaline phosphatase appears to be useful in the evaluation of osteitis fibrosa in patients with chronic renal failure both in cases with normal or elevated total alkaline-phosphatase values.

ISSN:1660-8151    

DOI:10.1159/000179928

出版商:S. Karger AG    

年代:1971

数据来源: Karger

摘要:

This is a case report of a 43-year-old housewife who developed acute polyneuritis as a terminal complication of chronic pyelonephritis. Death occurred from respiratory failure 18 days after the onset of neurological signs. The principal clinical findings were uraemia and a profound symmetrical weakness of the proximal muscles of the upper and lower limbs. There was also a moderate symmetrical weakness of the distal muscles of the upper and lower limbs. Limb reflexes, apart from the biceps jerks, were absent. There were no sensory abnormalities. Post mortem examination revealed chronic pyelonephritis with secondary hyperparathyroidism and osteitis fibrosa. At all levels of the spinal cord many motor neurones showed chromatolysis. There was degeneration of the terminal arborisations of the intramuscular nerves in distal limb muscles. There were no histological abnormalities in the spinal nerve roots and dorsal root ganglia nor in the extramuscular regions of the peripheral nerves. There was no histological evidence of a myopathy. It is suggested that the abnormalities in the intramuscular nerve fibres are due to a dying-back process of the spinal motor neurones, rather than to changes in the Schwann cells. The nature of the primary defect in the spinal motor neurones responsible for the dying-back phenomenon of the intramuscular nerve fibres is not known.

ISSN:1660-8151    

DOI:10.1159/000179929

出版商:S. Karger AG    

年代:1971

数据来源: Karger

摘要:

Serial determinations of serum renin activity (RA) have been made in 19 patients recipient of 21 allografts. Five patients received kidneys from 4 related and from 1 unrelated living donors; 13 patients received allografts from 15 adult cadavers, and 1 from an anencephalic newborn. During the first post transplant month observations were made in 18 recipients. RA was found increased transiently in 7 and persistently in 10 recipients. The increase in RA was associated with acute tubular necrosis, 5; occlusive vascular lesions of the graft artery or its branches and infarction of the graft, 4; cortical necrosis, 2; and acute rejection, 3. In 2 recipients no apparent cause for the rise in RA could be found, and in 1 the increase was probably related to diuretic therapy. During the late post transplant period, from 2 months to 2 years and 8 months, observations were made in 10 recipients. RA remained increased in 2 recipients with occlusive vascular lesions and rejection of the allograft, respectively. In 6 other recipients RA increased in association with rejection, 4; development of graft artery stenosis, 1; and diuretic therapy, 1. In 2 recipients with uneventful course RA remained normal. There was no statistically significant correlation between changes in RA and endogenous creatinine clearance, or body weight. However, there was a significant negative correlation between RA and sodium excretion, and a small positive correlation between RA and diastolic blood pressure.

ISSN:1660-8151    

DOI:10.1159/000179930

出版商:S. Karger AG    

年代:1971

数据来源: Karger

ISSN:1660-8151    

DOI:10.1159/000179931

出版商:S. Karger AG    

年代:1971

数据来源: Karger