摘要:

In a previously documented experimental model of acute renal failure in the rat (intravenous methemoglobin-ferrocyanide) 1 ml doses of 25% mannitol (1.21–1.54 g/kg) intravenously prevented both functional and histologic renal injury within –1 h and +30 min of attempted induction. When varying mannitol doses were given 15 min following attempted induction, a sigmoid log-log relationship of plasma urea nitrogen (PUN) concentration to mannitol dose was demonstrated. Mannitol doses above 300 mg/kg (at + 15 min) are estimated to be fully protective in the model. Similarly at 15 min following attempted induction, isosmolal 1 ml doses of aqueous mannitol, mannose, sucrose, sodium sulfate, sodium chloride, THAM [tris(hydroxymethyl)aminomethane] and thriceisosmolal urea prevented acute renal failure, but isosmolal urea and dextrose, isotonic saline and 6% human serum albumin did not. Both 6% dextran (av. mol. wt. 75,000) and 10% dextran (av. mol. wt. 40,000) intensified the lesions, possibly a unique reaction in the rat. Effective agents induced higher rates of urinary flow in anesthetized, normal rats than ineffective ones. The results indicate that, in this model, (a) several osmotic diuretic agents are capable of preventing acute renal failure; (b) preventive effectiveness correlates with the ability of an agent to induce prompt, brisk diuresis; (c) the preventive therapy must be timely to be effective; and (d) the probable protective mechanism is that the agent augments the pathogenetically-significant, reduced renal tubular fluid flow. The results also imply that the protective mechanism does not depend upon extracellular or plasma volume expansion, relief of renal ischemia, osmotic loading per se, or a specific chemical or pharmacological characteristic of any single ag

ISSN:1660-8151    

DOI:10.1159/000179422

出版商:S. Karger AG    

年代:1966

数据来源: Karger

摘要:

Electron microscopy of biopsy specimens from the renal cortex of 7 normal subjects showed that the small vessels could be divided into three groups. In the lobular artery and the first portion of the vas afferens there was a well-defined internal elastic lamina and a tunica media with one or more layers of typical smooth muscle cells. The juxtaglomerular part of the vas afferens was characterized by loss of internal elastic lamina and conversion of the muscle cells in the direction of the epitheloid form, with many granules. There was likewise no internal elastic lamina in the vas efferens, and its muscle cells contained only few myofilaments, but no characteristic granules. The ultrastructure of endothelium, muscle cells and interstitial tissue otherwise showed no features not described previously in animal tissue. The possibility of post-biopsy tissue changes is mentioned, and a short discussion is provided of the relationship between ultrastructure and function.

ISSN:1660-8151    

DOI:10.1159/000179423

出版商:S. Karger AG    

年代:1966

数据来源: Karger

摘要:

Two patients with vitamin D resistant rickets respond to a high phosphorus intake by a positive calcium balance. The response to a calcium infusion suggests a parathyroid effect on phosphaturia but the size and histology of the parathyroid glands in one patient was normal. A circadian phosphorus excretion rhythm was present.Studies of the effect of glucose on the renal handling of phosphorus in these patients suggest an inhibitory effect which is lacking in normals. It is postulated that one of two metabolic pathways for the renal tubular reabsorption of phosphorus is absent in vitamin D resistant rickets.

ISSN:1660-8151    

DOI:10.1159/000179424

出版商:S. Karger AG    

年代:1966

数据来源: Karger

摘要:

Renal blood flow was measured with the xenon-133 wash-out technique in a 40 year old woman during vasovagal syncope. During the attack renal blood flow was only 5% of the flow rate immediately after recovery. Thus it is very unlikely that there was a renal vasodilatation during the vasovagal syncope.

ISSN:1660-8151    

DOI:10.1159/000179425

出版商:S. Karger AG    

年代:1966

数据来源: Karger

ISSN:1660-8151    

DOI:10.1159/000179426

出版商:S. Karger AG    

年代:1966

数据来源: Karger

ISSN:1660-8151    

DOI:10.1159/000179427

出版商:S. Karger AG    

年代:1966

数据来源: Karger

ISSN:1660-8151    

DOI:10.1159/000179428

出版商:S. Karger AG    

年代:1966

数据来源: Karger