Glomerular permeability

Cojocel, C., Dociu, N., Maita, K., Sleight, S.D. and Hook, J.B. (1983). Effects of aminoglycosides on glomerular permeability, tubular reabsorption, and intracellular catabolism of the cationic low molecular weight protein lysozyme. Toxicol. Appl. Pharm. 39 129-139. 

Deen,W.M., M.J. Lazzara, and B.D. Myers. 2001. Structural determinants of glomerular permeability. Am. J. Physiol. Renal Physiol. 281 F579—596. Maack,T., C. Park, and M. Camargo. 1985. Renal filtration, transport and metabolism of proteins. In D. Seldin, and G. Giebisch (Eds.), The Kidney. 

Although hyperlipidemia may be partly reversed by the increase of plasma oncotic pressure with dextran infusion, decreased albumin and plasma oncotic pressure cannot fully explain nephrotic hyperlipidemia. In analbuminemic rats, lipid changes are different from those in nephrotic subjects (D4). There may be a direct causal link between proteinuria and lipid abnormalities because a 1 -acid glycoprotein isolated from urine of nephrotic patients may correct the impaired lipolysis of nephrotic rats (SI 6, K12). Thus, impaired lipoprotein metabolism may be caused by the loss of some regulatory substance into urine due to increased glomerular permeability. 

Recent progress in understanding podocyte biology in rare inherited glomerular diseases gives the chance to understand in the near future the molecular pathogenesis of increased glomerular permeability in the much more common acquired forms of nephrotic syndrome. 

Lindstroem KE, Blom A, Johnsson E, Haraldsson B, Fries E. High glomerular permeability of bikunin despite similarity in charge and hydrodynamic size to serum albumin. Kidney Int 1997 51 1053-1058. 

Transient proteinuria is common after aortography and selective nephroangiography, because of an increase in glomerular permeability. loxaglate, iopamidol, and iohexol cause only negligible proteinuria (SEDA-8, 428) (SEDA-11, 413). 

Remuzzi G, Bertani T. Is glomerulosclerosis a consequence of altered glomerular permeability to macromolecules Kidney Int 1990 38 384-394. 

In general, proteinuria reflects albuminuria. Albumin is readily measured by quantitative immunoassay methods capable of detecting urine albumin at low concentrations, and several groups have demonstrated that urinary total protein measurement can be replaced by that of urine albumin.This may provide a more specific and sensitive measure of changes in glomerular permeability and is... 

Any glomerular disease process may increase glomerular permeability as either a consequence of podocyte foot... 

CKD is invariably accompanied by a decrease in the number of viable nephrons. There is a compensatory increase in glomerular filtration in the remaining glomeruli, resulting in an increased filtered load of protein per nephron. In the absence of glomerular permeability changes, this wfll also give a tubular protein pattern. 

ACE inhibitors and ARBs slow the progression of diabetic kidney disease. A trial that was reported in 2000 confirmed that even nonmicroalbuminuric type 2 diabetic patients should be managed with ACE inhibitors or ARBs to prevent cardiovascular events.In addition to lowering systemic blood pressure, such patients also have lowered glomerular capillary blood pressure and protein filtration,ACE inhibitors and ARBs also reduce All-medi-ated effects on glomerular permeability and cell proliferation and fibrosis and should be incorporated into the treatment schedules of all patients with type 2 diabetes and those with type 1 diabetes and microalbuminuria, ACE inhibitors may exacerbate hyperkalemia in patients with advanced CKD and/or hyporeninemic hypoaldosteronism. In older patients with renal artery stenosis, they may cause a rapid decline in kidney function. Pooled data from large clinical trials indicated above show that only 1.5% of patients treated with ACE inhibitors or ARBs were withdrawn from trials because of hyperkalemia, and no deaths were reported as a consequence of hyperkalemia. ... 

Increased glomerular permeability for protein due to derangement in capillary walls is an early event in the nephrotic syndrome that has several causes, as listed below with examples ... 

A condition in which there is extensive protein loss in the urint due to increased glomerular permeability. The glomerula disorder may be a primary condition (e.g. some types o glomerulonephritis) or secondary to other conditions, such a amyloidosis, diabetes mellitus and systemic lupus erythematosu The resultant hypoalbuminaemia causes oedema. 

Lewis, E.J. and X. Xu, 2008. Abnormal glomerular permeability characteristics in diabetic nephropathy. Diabetes Care 31, 202-207. 

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