Dilated Glomerular Capillaries Research Articles

Virus-mediated Transduction of Apolipoprotein E (ApoE)-Sendai Develops Lipoprotein Glomerulopathy in ApoE-deficient Mice

Lipoprotein glomerulopathy (LPG) is a unique renal disease characterized by thrombus-like substances in markedly dilated glomerular capillaries, dysbetalipoproteinemia, and elevated plasma concentrations of apoE. Recent studies identified several apoE mutations in patients with LPG, including apoE2(R145P) Sendai (apoE-Sendai). Virus-mediated transduction of apoE-Sendai in apoE-deficient hypercholesterolemic mice resulted in insufficient correction of hypercholesterolemia and a marked and temporal induction of plasma triglyceride levels. In vitro binding studies showed that apoE-Sendai has a reduced affinity for the low density lipoprotein receptor, suggesting that dysbetalipoproteinemia in LPG is caused by the apoE mutation. Furthermore, histological examination revealed marked intraglomerular depositions of apoE-containing lipoproteins in mice injected with apoE-Sendai virus. These LPG-like depositions were detected 6 days after virus injection and were sustained for at least 60 days. Our results demonstrated that apoE-Sendai is an etiological cause of LPG.

Glomerular vascular changes in KK-Ay mice with early diabetes: scanning electron microscopy of vascular resin casts.

Vascular changes, the angioarchitecture of renal glomerular fine vessels in early diabetic KK-Ay mice of 4 months of age were examined by scanning electron microscopy of corrosion casts. Histologically, enlargement of glomeruli and dilation of glomerular capillaries were found. In resin cast specimens, glomeruli with diabetes were larger than normal, and an increase in diameter of the glomerular vessels was found in diabetic mice. No capillary proliferation, distortion of glomerular vessels and destruction of glomerular capillary loops were found in diabetic mice. The increased vascular diameter may explain the increase in blood flow in the glomeruli, affecting kidney function in early diabetes.

Light and electron microscopic descriptions of Sphaerospora coregoni El-Matbouli, Hoffmann and Kern, 1995 (Myxosporea: Sphaerosporidae) from the kidney of Whitefish ( Coregonus lavaretus)

Summary Sphaerospora coregoni El-Matbouli, Hoffmann and Kern, 1995 is described from the kidney of Coregonus lavaretus obtained from lake Constance and two other Bavarian lakes. Out of 80 fish (ranging in size from 25–35 cm and 200–250 g) twelve were found to be infected. The spores and pseudoplasmodia occurred in the lumen of the kidney tubules and inside the Bowman's capsules. The earliest pseudoplasmodia contained a primary cell and two secondary cells. All pseudoplasmodia were proved to be disporoblastic. Early pseudoplasmodia containing 12 cells were surrounded by a primary cell which was amorphous, rounded and measured 13.6 ± 0.8 μm in diameter. Spores in suturai view are prominent showing small protrusions at the anterior and the posterior end. Length of the spores was 8,2 μm (7.6 ± 8.6 μm) and their width including the lateral valves' thickness 11.3 μm (10.5 ± 12.4 μm). The two spherical polar capsules measure 1.9 μm (1.9 ± 2.0 μm). There were no apparent effects on the tubules during the sporogenic phase. However, infected renal corpuscles showed some dilatation of glomerular capillaries and Bowman's space. Data on ultrastructure and sporogenesis are presented.

Histological Changes in Cultured Lake Trout, Salvelinus namaycush, Subjected to Cumulative Loading in a Water Reuse System

Lake trout (Salvelinus namaycush), 16 cm long, were reared 8 wk in five serial reuse units, resulting in cumulative loadings of 1.5–7.5 kg fish∙L−1∙min−1. Although mean un-ionized ammonia concentrations in the highest loading levels were less than 10% of those often considered as safe for culture of rainbow trout (Salmo gairdneri), lake trout reared at the higher loading levels showed dilation of glomerular capillaries, a condition that persisted after cumulative loading conditions were removed, and gill epithelial hyperplasia and hypertrophy. We observed lamellar telangiectasis caused by sampling technique. We conclude that parameters other than ammonia concentrations are significant factors in branchial irritation.

Renal pathology of fetuses with congenital nephrotic syndrome of the Finnish type. A qualitative and quantitative light microscopic study.

A light microscopic study was performed on 10 fetal kidneys of congenital nephrosis of the Finnish type (CNF) and compared to 22 controls. The gestational age of the fetuses ranged from 16 to 24 weeks. A quantitative morphometric analysis was carried out on 6 CNF fetuses and 6 age-matched controls. The organogenesis of the kidney and the nephrogenesis proceeded normally in CNF. The size and the number of glomeruli were the same in CNF and controls. An increase in the proportion of mature glomeruli and a decrease in the percentage of visceral epithelial cells in them suggested accelerated glomerular maturation in CNF. Focal mesangial cell hyperplasia and dilatation of glomerular capillaries with congestion of blood were more often obvious in CNF than in controls. Marked dilatation of proximal tubular lumens and Bowman's spaces were typical in CNF.

Liquoid Induced Stasis and the Generalized Shwartzman Reaction

The composition of the occlusive material within dilated glomerular capillaries, following intravenous injections of Liquoid in blue foxes, was studied electron microscopically; it was found that it mainly consisted of a debris in which disintegrated red cells constituted the major component. Damaged platelets and necrotic endothelial remnants were other components. These observations were interpreted as a result of glomerular stasis, and it was concluded that stasis in glomerular capillaries is a basic event in the development of the renal lesions accompanying the generalized Shwartzman reaction.

Glomerular lesions in rats treated with homologous blood-in-adjuvant emulsion

Rats were injected intraperitoneally, twice a month, for varying periods with homologous blood emulsified in Freund's complete adjuvant. Kidneys of animals treated for seven months or less, and those of the majority of rats injected for eight to ten months exhibited, at most, mild glomerular lesions compatible with adjuvant effects. However, conspicuous glomerular damage ensued in a minority of rats treated for eight to ten months; in two of six affected kidneys, dilated glomerular capillaries were occluded by an amorphous or granular material. The etiology of the renal disease described is probably immunogenic, though the precise pathogenesis remains obscure.

Ocular changes in the Shwartzman reaction. Their possible relationship to diabetic retinopathy.

The generalized Shwartzman reaction is produced, classically, in rabbits by 2 appropriately-spaced intravenous injections of Gram-negative bacterial endotoxin and is characterized by the precipitation of eosinophilic, periodic acid-Schiff (PAS)-positive material in the vasculature of many organs including kidney, liver, lung, and spleen.2,3There often occurs in this reaction glomerular capillary dilatation and the deposition within such capillaries of PAS-positive material.4This finding suggested the possibility of similar dilatations in the retinal capillaries in the generalized Shwartzman reaction. The appearance of the glomeruli in the generalized Shwartzman reaction (Fig. 1) suggests similarity to that described in the Kimmelstiel-Wilson lesion5(Fig. 2). There is evidence for the coincidence of retinopathy and the Kimmelstiel-Wilson lesion in diabetes mellitus.6,7In diabetic retinopathy aneurysmal dilatations are found on both the venous and arterial sides of the capillaries and, less frequently, in small veins. The aneurysms may be mere out-pouchings of the

Some Observations on Circulatory Changes in a Renal Glomerulus

In a female Necturus, anesthetized with urethane, a glomerulus showing sluggish blood flow was observed; the capillary loops were dilated, although not uniformly. The picture was unchanged by pithing the brain. This glomerulus was peculiar in that both afferent and efferent vessels were clearly seen; the afferent vessel came direct from a large ovarian artery. There was no alternation of flow. The afferent vessel was now stroked gently with a fine glass rod; there was no response. More vigorous stroking resulted in a shifting of the kidney region in the field after about a 5 second latent period; this was followed in 5 seconds more by constriction of the afferent vessel to the point of cessation, complete or practically so, of cell movement in the glomerulus. The shifting of the kidney region preceding afferent vessel constriction was seen to be due to a contraction of the ovarian artery from which the afferent vessel sprang, resulting in a tugging on the kidney. It was then found that traction on the ovarian artery was an adequate stimulus to this vasoconstriction, which spread from the artery to the afferent vessel. After this experiment had been repeated a few times at intervals of 3 or 4 minutes the phenomenon would occur without external stimulation; previous to its first production the flow had been steady for the 20 minute period of observation. Both between and during periods of afferent vessel constriction the efferent vessel was seen to be constantly constricted, being narrower than the narrowest loop in the capillary tuft. Cells passed through it rapidly and in single file. Actual observation of such a constricted efferent vessel strengthens an idea which has been held for some time, that the slow blood flow through dilated glomerular capillaries at a time when the general circulation is vigorous is due to efferent vessel spasm.

利尿劑竝ニ其他ノ藥劑ノ腎臟絲毬體ニ及ボス作用ニ就テ

From the results of my experiments the conclusion may be summarized as follows. 1. Caffeine, caffeine sodio-benzoate and diuretin have dilator effect upon the glomerular capillaries and the circulation in them becomes more rapid. The quantity of blood which flows through them increases and a number of glomeruli, hitherto unobserved, become visible. On the other hand, theocin and glucose have no effect upon the glomeruli. 2. Solution of potassium acetate causes a remarkable contraction and at the same time the glomeruli till then observed, become invisible. 3. Kreatin produces a dilatation of glomerular capillaries and accordingly the circulation in them becomes more rapid and also the number of glomeruli increased. Guanidin in a solution weaker than 0.4 p. c. causes dilatation of glomerular capillaries and increase of the quantity of blood which flows through them and also it causes the increase of verocity of blood flow in the glomerular capillaries. The glomeruli, hitherto stationary, become active and the number of them increases. On the contrary, a solution stronger than 0.5 p. c. always causes contraction of glomerular capillaries and the number of glomeruli are decreased. 4. Isotonic solution (with 0.6% Ringer's solution) of NaNO(2), NaNO(3) and Na(2)HPO(4) causes a slight dilatation of glomerular capillaries and accordingly the increase of verocity of blood flow in them and of quantity of blood flowing through them are produced. But other sodium salts have no effect upon the glomeruli. All of potassium salts, on the contrary, have an opposite effect upon the glomeruli to that of sodium salts. 5. Calcium salts and magnesium salts (isotonic with 0.6% Ringer's solution) and some organic substances (m/100 in density) have a remarkable dilator effect upou the glomerular capillaries and cause the increase of verocity of blood flow in them and of quantity of blood which flows through them. Glomeruli are increased in number und are remarkably congested and swollen.