Differences in puromycin aminonucleoside nephrosis in two rat strains

Kidney International, Vol. 33 (1988), pp. 524—529

Differences in puromycin aminonucleoside nephrosis in two rat strains JoRIs GROND, ERIK W. MULLER, HARRY VAN GooR, JAN J. WEENING, and JOB D. ELEMA Departments of Pathology and Internal Medicine, University of Groningen, and Department of Pathology, University of Leiden, The Netherlands

Differences in puromycin aminonucleoside nephrosls in two rat strains. Administration of puromycin aminonucleoside (PAN) to Wistar rats induces proteinuria and enhanced mesangial deposition of circulating macromolecules. After proteinuria of longer duration focal and segmental glomerular hyalinosis and sclerosis (FSGHS) develops, The present report analyzes these aspects of PAN nephrosis in PVG/c rats, a strain previously shown to be remarkably resistant to proteinuria and FSGHS with aging or after uninephrectomy. In Wistar rats multiple injections of PAN during five months resulted in sustained severe proteinuria and FSGHS lesions in 8.1 1.0% (mean I sEM) of their glomeruli (N = 6). In PVG/c rats a 1.3-fold higher dose of PAN was needed to induce chronic proteinuria similar to the Wistar rats. After five months 3.3 0.9% of their glomeruli showed FSGHS (N = 6, P < 0.01) and the glomerular lesions were considerably less advanced. In acute PAN nephrosis induced by a single intravenous injection of PAN the mesan-

gium of Wistar rats contained large amounts of lipid in contrast to a few small mesangial lipid droplets in nephrotic PVG/c rats. After injection

of colloidal carbon in nephrotic PVG/c rats no enhanced carbon accumulation was found in the mesangium when compared to nonproteinuric controls. This result clearly differs from the increased mesangial sequestration of circulating material in nephrotic Wistar, and most other rat strains. The unchanged mesangial traficking of macro-

molecules in nephrotic PVG/c rats and the low incidence of FSGHS lesions in the presence of sustained glomerular proteinuria may reflect a relative resistance to PAN-induced glomerular damage in this particular rat strain.

hypertensive strain [4]. Recently, we documented a remarkable resistancy of rats of the PVG/c strain to FSGHS upon aging or

after unilateral nephrectomy [5]. The present study extends these observations and reports a relatively low incidence of FSGHS associated with a strikingly normal mesangial handling of macromolecules in PVG/c rats with puromycin aminonucleoside nephrosis. Methods Animals Male Wistar rats and inbred PVG/c rats (haplotype RT1 . c/c) were obtained from the same colonies as used in the previous study [5]. All animals were three months of age at the start of

the experiments. They were fed a normal rat chow with a sodium content of 0.44% and a digestible protein content of 22%

(Hope Farms, Woerden, The Netherlands) with free access to tap water. Proteinuria Urine was collected from rats housed for 24 hours in metabolic cages with access to tap water only. Protein excretion was measured with the biuret method.

Chronic puromycin aminonucleoside nephrosis Six Wistar and six PVGIc rats were injected subcutaneously puromycin aminonucleoside (PAN, Sigma Chemical Co., failure. Aging male rats of most strains gradually develop with St. Louis, Missouri, USA). In Wistar rats a dose of 20 mg per proteinuria associated with progressive renal functional deterikg body weight dissolved in 1 ml of saline was given weekly oration and structural alterations, such as focal and segmental during the first three weeks, and subsequently 10 mg per kg glomerular hyalinosis and sclerosis (FSGHS), much resembling body weight every other week [6, 7]. The dose of PAN chronic renal disease in man. The development of FSGHS in administered to the PVG/c rats was increased in such a way that rats can be accelerated by a variety of stimuli such as surgical mean proteinuria of the PVG/c rats was comparable to that of removal of variable amounts of kidney tissue, renal infarction, the Wistar rats. Proteinuria was measured weekly. Seven rats irradiation, induction of diabetes mellitus, hormonal treatment, of both strains were injected with 1 ml of saline at the same time immunologic injury to the kidneys, injections of nephrotoxic intervals and served as controls. All animals were killed after agents, and combinations of these maneuvers [1]. Not all rat

A large number of animal models is now available to study etiologic, pathogenetic, and therapeutic aspects of chronic renal

five months. Kidney tissue was fixed by immersion in 8% strains bear the same susceptibility for the development of buffered formalin for 24 to 48 hours at room temperature and FSGHS [2]. No development of age-dependent FSGHS has embedded in glycol methacrylate. Sections were cut at 2 sm on been reported in Wistar Kyoto rats [3] and rats of the Milan a Sorvall-JB-4 microtome and stained with periodic acid Schiff

(PAS). Coronal sections (two per kidney with an interspace of

150 pm) of both kidneys of each rat were screened at a Received for publication March 6, 1987 and in revised form June 22, 1987

© 1988 by the International Society of Nephrology

magnification of x 250 by light microscopy to determine the percentage of glomeruli with FSGHS. Per kidney at least 100 glomeruli were studied. FSGHS was defined according to the 524

525

Grond et a!: Aminonucleoside nephrosis in rats

criteria put forward by Habib [81 consisting of a glomerular mg of PAN per kg body weight dissolved in 3 ml of isotonic lesion with deposition of hyalin amorphous material in mesan- saline was injected into seven male PVG/c rats. Five controls glum and subendothelium ("hyalinosis") with increase of received saline. Before and seven days after PAN injection mesangial matrix material, capillary lumen obliteration with urine was collected for protein determination. At day 9 all collapse, and synechiae to the Bowman's capsule ("sclerosis"). animals received 20 mg CC per 100 g of body weight intraveThe degree of damage in the affected glomeruli was scored nously (CC for biological use, Cl 111431A, Gunther Wagner, semiquantitatively from 0 to 4 according to the percentage of Hannover, Germany, containing 100 mg of CC per ml). Blood glomerular involvement as designed by Raij, Azar and Keane levels of carbon were measured by optical density at a wave [9]. In this system a l lesion represents 25% involvement of length of 650 nm and the phagocytic index K, which characterthe glomerulus and a 4 lesion complete glomerular hyaliniza- izes the rate of CC clearance from the circulation, was calcution. lated. Biopsies were taken from the right kidney via a flank incision under ether anesthesia at 24 hours after CC injection. Acute puromycin aminonucleoside nephrosis Kidneys were obtained at autopsy after seven days. The After a single intravenous injection of PAN (acute PAN material was fixed by immersion and embedded in plastic. One nephrosis) Wistar rats of our colonies show a considerably set of slides of 2 m thickness was stained with PAS for light enhanced mesangial accumulation of endogenous lipids [61 and microscopic study, another set of slides was left unstained for intravenously injected tracer such as colloidal carbon [10]. This the measurement of the amount of mesangial CC using the well known effect of PAN on the mesangium has been reported Optomax system. In each tissue specimen measurements were by many authors in other rat strains as well [11—13]. In the made of 25 consecutive glomeruli and mean count number per present experiments mesangial macromolecular kinetics in glomerulus was taken as a measure of mesangial carbon content PVG/c rats with acute PAN nephrosis were studied. Mesangial of that kidney or biopsy. For a more detailed analysis, glomeruli lipid content of nephrotic Wistar rats was compared to that of of the PAN and control rats at the 24 hour interval after CC PVG/c rats after PAN injection. In these experiments five injection were grouped in classes of increasing count number Wistar rats received a single intravenous injection of 60 mg of with a class range of 30 counts [7, 15]. PAN per kg body weight dissolved in 3 ml of isotonic saline. Statistical analysis Since preliminary studies indicated that PVG/c rats were considerably less sensitive to the nephrotoxic effect of PAN, a Values are presented as mean 1 standard error of the mean group of 10 PVGIc rats received a dose of 150mg of PAN per kg

(sEM). Statistical evaluation was carried out using the two-sided body weight intravenously. Urine was collected from day 9 to Student's t-test or the Mann-Whitney U test, with the level of 10 to measure protein excretion. The animals were killed on day significance being defined as P < 0.05.

10 and blood was collected for determination of the serum levels of cholesterol. The group of Wistar rats was matched with five PVG/c rats with similar levels of serum cholesterol being the lipid preferentially deposited in glomeruli during PAN nephrosis [14]. For the detection of glomerular lipid, tissue from

both kidneys was snap-frozen in precooled Freon at —90°C. Cryostat sections (3 sm) were stained with Oil Red 0. For light microscopic examination the sections were counterstained with hematoxylin. For semiquantitative analysis of glomerular lipid ORO-stained sections without counterstaining were measured with the use of a modular scanning image analyzer (Optomax, Ealing Beck, Ltd., Whatford, UK). As described previously [6, 7], this method is a point counting method in which the total number of points covered by a contrasted area is counted and serves as a measure of the total area of ORO-positive material present in the glomerulus. The threshold of sensitivity was

Results

Chronic puromycin aminonucleoside nephrosis

At the start of this experiment mean body weight of the Wistar group was 233 3 g (N = 13), of the PVG/c group 255 3 g (N = 13). Mean body weight of Wistar rats after five months of repeated PAN injections was 398 12 g (N = 6), of saline injected controls it was 409 14 g (N = 7, NS). Both

nephrotic and control PVG/c rats showed a lower weight gain. At sacrifice mean body weight of the nephrotic PVG/c rats was 338 4 g (N = 6), of saline injected controls 349 4 g (N = 7, NS). Protein excretion in PAN-injected Wistar and PVG/c rats is illustrated in Figure 1. Mean protein excretion during the experimental period of five months in the Wistar rats was 145 12 mg, in the PAN-injected PVG/c rats it was 131 11 mg per chosen in such a way that only ORO-positive areas gave 24 hours (NS). The total amount of PAN required to induce and sufficient contrast for detection by the scanner. All measure- maintain protein excretion of the PVG/c rats, similar to that of ments were performed using the same level of sensitivity. In the Wistar rats, was 200 mg per kg body weight. Wistar rats each section 25 consecutive glomeruli sectioned through their received a total amount of 150 mg per kg body weight. Protein largest or nearby largest diameter were scanned moving excretion in saline-injected control Wistar rats was 26 2 mg, through the cortex from surface to medulla and vice versa. in control PVG/c rats it was 27 3 mg per 24 hours. Mean count number per glomerulus was taken as a measure of Characteristic FSGHS lesions consisting of segmental glomerular lipid content of that rat and the mean count numbers mesangial and subendothelial deposition of hyalinized PASof all rats as the value of the group. In addition, mesangial positive material with an increase of mesangial matrix submacromolecular kinetics in PVG/c rats were further studied by stance, capillary wall wrinkling with collapse, and synechiae to comparison of mesangial processing of i.v. injected colloidal the Bowman capsule were found at autopsy in kidneys of both

carbon (CC) of nephrotic PVG/c rats with that of non- Wistar and PVG/c rats (Fig. 2, Table 1). In both strains the proteinuric controls, exactly following the procedure used affected glomeruli were distributed equally in the juxtamepreviously by us in Wistar rats [6, 10]. A single i.v. dose of 90

dullary and outer position of the cortex, and no stratification of

Grond el a!: Aminonucleoside nephrosis in rats

526 400

.!

Table 1. Glomerular pathology in Wistar and PVG/c rats after chronic PAN nephrosis of 5 months duration Percentage glomeruli with FSGHS

200

mean 1 SEM

C 0)

WistarN= 6 PVG/c N = 6

0

0 A AA 0

£ £AAkLIP 5

20

15

10

Time, weeks

8.1 3.3

1.0

0.9

Degree of damage in FSGHS glomeruli %

1

234

32 73

41 25

Glomerular lipid

repetitive subcutaneous injections of 20 mg per kg (Large arrow heads) and 10 mg per kg body weight (small arrow heads).

Serum cholesterol mmol/liter

WistarN 5

•.E • e,ga —-

'b

PVG/cN=5

11.1

1.0

10.2± 1.4 NS

•1

5 0

Table 2. Serum cholesterol levels, proteinuria, and glomerular lipid content of Wistar and PVG/c rats injected 10 days previously with 60 mg and 150 mg of PAN per kg body weight, respectively (mean values 1 SEM)

Fig. 1. Proteinuria of Wistar (W) and PVG/c (PP) rats in response to

—

22 2

Proteinuria mg/24 hr 330

43

180±23

P < 0.01

countsl glomerulus 48.9 13.0

7.6±2.1

P < 0.025

'1%

-I.-.-

I

•

jI

.1 I I-

a

(normal value less than 1.7 mmol/liter in both strains). However, proteinuria of Wistar rats significantly exceeded that of the selected PVG/c rats despite a lower dose of PAN. Light microscopic examination did not reveal glomerular lesions in Wistar or PVG!c kidneys apart from numerous protein droplets in visceral epithelium. ORO-staining disclosed many small and large lipid deposits in the glomeruli of Wistar rats located in a mesangial pattern (Fig. 3A). Glomeruli of PVG/c rats contained

,' /4S a-

D

Fig, 2, Glomerulus of PVG/c rat after 5 months of persistent proteinuria. A 2 FSGHS lesion is shown with insudations, capillary lumen

obliteration and collapse, and adhesions to the Bowman's capsule. PAS, x 350.

the lesions was observed. Compared to Wistar rats the percentage of glomeruli showing FSGHS in PVG/c kidneys was signif-

icantly lower with considerably less extended glomerular involvement (Table 1). Numerous protein absorption droplets were observed in glomerular visceral epithelial cells of sclerotic and non-sclerotic glomeruli of both strains. The kidneys further showed focal tubular atrophy, tubular intraluminal protein casts, patchy chronic inflammatory infiltrate, and protein droplets in tubular epithelium. Acute puromycin aminonucleoside nephrosis Both Wistar and PVG/c rats were heavily nephrotic 10 days after PAN injection. At autopsy ascites was marked, particu-

only a few small lipid droplets (Fig. 3B). Semiquantitative analysis showed significantly larger quantities of glomerular lipid in Wistar rats compared to that in PVG/c rats (Table 2). No

mesangial lipid deposits were found in glomeruli of normal Wistar and PVG/c rats. Mean urinary protein excretion in the PAN-injected PVG/c rats used in the carbon studies was 123 8 mg per 24 hours (N = 7) at day 7; in saline-injected controls mean level of urinary protein was 15 6 mg per 24 hours (P < 0.001). CC clearance from the blood did not differ between nephrotic and control rats 0.0161 0,0014, CC blood level at 5 minutes 3.28 (KPAN mg/mI; Kontrois = 0.0170 0.0016, CC blood level at 5 minutes 3.19 mg/mi). Light microscopic examination did not reveal differences in mesangial CC content between nephrotic and control PVG/c rats one day (Fig. 4) and seven days after CC injection. In both groups there was considerable variation in the quantity of CC among glomeruli and within the lobules of the glomeruli. The quantity of CC did not differ between superficial and juxtamedullary glomeruli. Semiquantitative analysis of the amount of mesangial carbon is presented in Table 3. Neither at one day nor at seven days after CC injection were differences found between nephrotic and control PVG/c rats. When the frequency distribution of glomeruli over the different count

classes of nephrotic rats was compared to that of controls, identical distribution patterns were found (Fig. 5).

Discussion larly in the PVGIc rats. Table 2 shows the biochemical and This report extends previous studies that have examined morphological data. To compare mesangial lipid the animals were matched on the basis of serum cholesterol levels, these strain differences in the development of proteinuria and FSGHS being approximately tenfold increased in both groups of rats with aging and the acceleration of these changes with

527

Grond et a!: Aminonucleoside nephrosis in rats

t--. &..,. 1

-

.1 --

S 4'

z.

S

y--'

St •.

• V;41

.':

.4,

-. tIi A

R -'24 -- -

.0

'a -a -a

—,

s-s.c arn'.

. ., :4 .5 ft. e 4

4

•t —

•. -.-

-'1%34; — -

4.,

-

¼

- IT'!

Fig. 3A. Glomerulus of a Wistar rat 10 days

after intravenous injection of 60 mg of PAN per kg body weight. Many small and large lipid droplets are present in a mesangial pattern (arrow heads). ORO and Hematoxylin, x 350. B. Glomerulus of a PVG/c rat 10 days after PAN injection (150 mg per kg body weight). A few small lipid deposits are seen (arrow heads). ORO and Hematoxylin,

x 350.

'4

*-

tH

—-

Vt-

Fig. 4A. Glomerulus of a PAN injected PVG/c rat with heavy proteinuria 24 hours after CC injection, CC is localized in the glomerular mesangial area. Protein reabsorption droplets are present in the glomerular epithelium (arrow). PAS, x 560. B. Glomerulus of a control PVG/c rat. The amount of CC localized in the mesangium 24 hours after intravenous injection is equal to that in Figure 5A. PAS, x 560.

uninephrectomy [5]. In the current experiments rats of this particular FSGHS-resistant PVGIc strain were found to be

However, the relatively modest proteinuria in response to PAN injection when compared to Wistar and most other rat strains remarkably less sensitive to the proteinuric effect of PAN when may indicate an uncommon metabolism of glomerular visceral compared to Wistar rats. In chronic PAN nephrosis higher epithelial cells in PVG/c rats. Interestingly, administration of doses of PAN were needed to induce proteinuria in PVG/c rats adriamycin, another nephrotoxic agent causing epithelial cell equal to Wistar rats. In acute PAN nephrosis PVG/c rats even damage and proteinuria in rats by a direct toxic effect on the failed to reach the urinary protein levels of Wistar rats, despite kidney [6, 20], to PVG/c rats likewise induced a relatively low a more than 200 per cent higher intravenous dosage of PAN proteinuric response when compared with Wistar rats [21]. Aging and uninephrectomized rats which develop FSGHS (Table 2). PAN exerts a rapid direct biochemical effect on the kidney independent of any systemic effect, as shown by Hoyer lesions already show increased urinary protein loss before and coworkers in transplantation and selective renal perfusion glomerular hyalinosis and sclerosis have developed [22—25] and experiments [12, 161, although the proteinuria occurs after a lag this is even more clear in rats made proteinuric by injections period of several days. Although many studies, both in vivo and with PAN [6, 7, 26, 27]. Thus, proteinuria and development of in vitro, have been addressed to this model, and in particular FSGHS seem to be strictly related phenomena although the have focused on the morphological and biochemical changes of question remains whether they are causally related or separate the visceral glomerular epithelial cell [17—19], the precise bio- expressions of glomerular injury [6]. The present data show that chemical insult at the cellular level is not entirely clear. Our when PVGIc rats are made proteinuric by high dosages of PAN, current study cannot make further contributions on this issue. they indeed develop FSGHS be it in a low percentage of their

528

Grond et a!: Aminonucleoside nephrosis in rats

Table 3. Mesangial carbon content at 1 and 7 days after injection into

nephrotic (PAN) and control (Saline) PVG/c rats (mean count number 1 5EM) 7 days

1 day

PANN= 7

Saline N = 5

P

3.3±

15.1±2.3

4.2

2.4

18.7

1.4 1.8

NS

NS

8

A

sections of Wistar and PVG/c rats matched on serum cholesterol levels using circulating lipids as an "endogenous tracer" [6, 14] indicated only modest lipid accumulation in the mesangium of nephrotic PVG/c rats, in contrast to large lipid deposits in glomeruli of Wistar rats. Matching on serum lipid levels resulted in different levels of urinary protein excretion between these groups of rats with acute PAN nephrosis (Table 2). Many authors, however, have shown that the sequestration of injected CC, aggregated IgG, or immune complexes in PAN nephrosis [11, 12, 42], nephrotoxic serum nephritis [42, 43], autologous immune complex glomerulonephritis [13, 44,45] and

100

adriamycin nephrosis [6, 131 is not directly related to the magnitude of proteinuria. In contrast to the considerably enhanced mesangial deposition of CC, aggregated IgG, and lipids

in PAN-injected Sprague-Dawley, Lewis, and Wistar rats [10—12, 42] the uptake and removal of CC by the mesangium of

000000000Q000000'

a ILL,L.L,LL.La

ii I

I IiiilIiIIIIa

counts glomerulus

Fig. 5. Frequency distribution of glomeruli of normal and nephrotic

PVG/c rats in the different classes of carbon counts 24 hours after CC injection. Symbols are: (U) saline; U PAN.

glomeruli with considerably less extended glomerular involvement than in Wistar rats.

The pathogenesis of FSGHS is only partially understood.

nephrotic PVG/c rats was identical to that of non-proteinuric controls. This unmodified mesangial handling of circulating macromolecules in PVG/c rats with PAN nephrosis constitutes a crucial observation in this study, although the mechanism underlying this phenomenon remains unexplained from our data. The relatively low occurrence of FSGHS in this particular rat strain may be related to this unchanged mesangial behavior in the presence of severe proteinuria [39]. Acknowledgments This study was financially supported by the Dutch Kidney Foundation. The authors thank Mr. Hilbrand Wierenga for photographic assistance.

Reprint requests to J. Grond, M.D., Department of Pathology, University of Gronigen, Oostersingel 63, 9713 EZ Gronigen, The

Netherlands.

Many experimental models, mainly in rats, have been described in which FSGHS-like lesions develop [1, 2]. Suggestions for a

pathogenesis of these glomerular lesions include amino acid toxicity [28, 291, impaired cellular immunity [30, 31], mechanical stress due to intraglomerular hypertension and hyperperfusion [32, 33], coagulation [34, 351, damage of visceral epithelium with development of synechiae and capillary collapse [27, 36], abnormalities of mesangial cell growth regulation secondary to

visceral epithelial and endothelial cell injury [36—38], and mesangial changes associated with or caused by accumulations of proteins and lipids with matrix overproduction and scarring, analogous to arterial wall damage in atherosclerosis [6, 14, 15, 22, 39]. Evolution of the glomerular morphologic changes in the rat associated with hyperfiltration secondary to ablation of renal mass (uninephrectomy and partial infarction of the contralateral kidney) are documented by Rennke [331. Four basic pathologic processes ultimately lead to glomerulosclerosis: microthrombosis, microaneurysma formation, subendothelial hyalin deposi-

References 1. BRENNER BM, MEYERTW, HO5TETTER TH: Dietary protein intake

and the progressive nature of kidney disease: The role of hemodynamically mediated glomerular injury in the pathogenesis of progressive glomerular sclerosis in aging, renal ablation, and intrinsic renal disease. N Engl J Med 307:652—59, 1982 2. WEENINC JJ, BEUKERs JJB, GROND J, ELEMA JD: Genetic factors in focal segmental glomerulosclerosis, Kidney mt 29:789—798, 1986 3. FELD LG, VAN LIEw JB, BRENTJEN5 JR, BOYLAN JW, BERBEN 5,

CHANG H, MANZ N: Renal lesions and proteinuria in the spontaneously hypertensive rat made normotensive by treatment. Kidney mt 20:606—614, 1981

4. BRANDI5 A, BIANcHI G, REALE E, HELMCHEN U, KUHN KW: Age-dependent glomerulosclerosis and proteinuria occurring in rats

of the Milan normotensive strain and not in rats of the Milan

hypertensive strain, Lab Invest 55:234—243, 1986 5. GROND J, BauscaRs JJB, ScHILTHuI5 MS, WEENJNG JJ, ELEMA

FSGHS however, hyperfiltration is absent, at least in its early

JD: Analysis of renal structural and functional features in two rat strains with a different susceptibility to glomerular sclerosis. Lab Invest 54:77—83, 1986 6. GROND J, WEaNING ii, ELEMA JD: Glomerular sclerosis in nephrotic rats. Comparison of the long-term effects of adriamycin and

phases, with markedly decreased glomerular filtration and

7.

tion, and mesangial expansion [331. In the PAN model of plasma flow rates [40, 411. Epithelial and mesangial damage may be more important determinants of FSGHS in this model [7, 17, 19, 27, 36, 371. On the basis of previous own observations in Wistar rats with chronic PAN nephrosis [6, 7], attention was paid to the mesangial handling of circulating endogenous

aminonueleoside. Lab Invest 51:277—285, 1984 GROND J, KOUDSTAAL J, ELEMA ID: Mesangial function and

glomerular sclerosis in rats with aminonucleoside nephrosis. Kidney mt 27:405—410, 1985

HABIB R: Focal glomerular sclerosis. Kidney mt 4: 355—361, 1973 9. RAn L, AZAR 5, KEANE W: Mesangial immune injury, hypertension, and progressive glomerular damage in Dahl rats. Kidney mt 8.

26:137—143, 1984

lipids and injected colloidal carbon in PVG/c rats made 10. GROND I, ELEMA ID: Glomerular mesangium. Analysis of the proteinuric with PAN. Morphometric analysis of ORO-stained

increased activity observed in experimental acute aminonucleoside

Grond et al: Aminonucleoside nephrosis in rats

nephrosis in the rat. Lab Invest 45:400—409, 1981 11. MAUER SM, FIsH AJ, BLAU EB, MICHAEL AF: The glomerular mesangium, I. Kinetic studies of macromolecular uptake in normal and nephrotic rats. J Gun Invest 51:1092—1101, 1972 12. HOYER JR, MAUER SM, MICHAEL AF: Unilateral renal disease in the rat. I. Clinical, morphologic, and glomerular mesangial functional features of the experimental model produced by renal perfusion with aminonucleoside. J Lab Gun Med 85:756—768, 1975 13. KEANE WF, RAIJ L: Relationship among altered glomerular barrier

529

various protein diets on growth, renal function, and survival of uremic rats. Kidney Int 15:534—541, 1979 30. GUTTMAN PH, BAILEY DW: Potentiating effect of neonatal thymectomy on X-ray induced intercapillary glomerulosclerosis. Nature 207:534—540, 1965

31. MATSUMOTO K, OSAKABE K, KATAYAMA H, YOSHIZAWA N, NAGURA Y, HARADA M, FUJITA T, OHI H, HATANO M: Impaired

cell-mediated immunity in focal glomerular sclerosis. Nephron

perm selectivity, angiotensin II, and mesangial uptake of macro-

34:220—223, 1983 32. HOSTETTER TH, OLSON JL, RENNKE HG, VENKATACHALAM MA,

molecules. Lab Invest 52:599—604, 1985 14. GROND J, VAN GooR H, ERKELENS DW, ELEMA JD: Glomerular

BRENNER BM: Hyperfiltration in remnant nephrons: A potentially adverse response to renal ablation. Am J Physiol 241 :F85—F93,

sclerotic lesions in the rat. Histochemical analysis of their macro-

1981

molecular and cellular composition. Virchow Arch 51:521—534, 1986 15. GROND J, SCHILTHUIS MS, KOUDSTAAL J, ELEMA JD: Mesangial

33. RENNKE HG: Structural alterations associated with glomerular hyperfiltration, in The Progressive Nature of Renal Disease, edited

function and glomerular sclerosis in rats after unilateral nephrec-

by MITCH WE, BRENNER BM, STEIN JH, Churchill Livingstone New York, Edinburgh, London, Melbourne, 1986, pp. 111—131 34. PURKERSON ML, HOFFSTEN PE, KLAHR 5: Pathogenesis of the glomerulopathy associated with renal infarction in rats. Kidney Int

tomy. Kidney mt 22:338—343, 1982

16. HOYER JR, RATTE J, POTTER AH, MICHAEL AF: Transfer of aminonucleoside nephrosis by renal transplantation. J C/in Invest 51:2777—2780, 1972

17. FISHMAN AJ, KARNOVSKY MJ: Effects of aminonucleoside of

puromycin on glomerular epithelial cells in vitro. Am J Pathol 118:398—407, 1985 18. KERJASCHKI D, VERNILLO A, FARQUHAR MG: Reduced sialysation

of podocalyxin, the major sialoprotein of the rat kidney glomerulus, in amjnonucleoside nephrosis. Am J Pathol 118:343—349, 1985 19. DIAMOND JR, BONVENTRE JV, KARNOVSKY Mi: A role for oxygen free radicals in aminonucleoside nephrosis. Kidney mt 29:478—483, 1986

9:407—417, 1976

35. Osor' JL: Role of heparin as a protective agent following reduction of renal mass. Kidney Int 25:376—382, 1984 36. VELOSA JA, GLASSER RJ, NEVINS TE, MICHAEL AF: Experimental

model of focal sclerosis. II. Correlation with immunopathologic changes, macromolecular kinetics, and polyanion loss. Lab Invest 36:527—534, 1977

37. DIAMOND JR, KARNOVSKY Mi: Focal and segmental glomerulosclerosis following a single intravenous dose of puromycin aminonucleoside. Am J Pathol 122:481—487, 1986

20. BERTANI T, POGGI A, OZZONI R, DELAINI F, SACCHI G, THOUA

38. CASTELLOT JJ, HOOVER RL, HARPER PA, KARNOVSKY Mi: Hep-

Y, MECCA G, REMUZZI G, DONATI MB: Adriamycin-induced nephrotic syndrome in rats. Sequence of pathologic events. Lab

arm and glomerular epithelial cell-secreted heparin-like species

Invest 46:16—23, 1982 21. GROND J, WEENING JJ, VAN GooR H, ELEMA JD: Application of

puromycin aminonucleoside and adriamycin to induce chronic renal failure in the rat. Contr Nephrol (in press)

inhibit mesangial cell proliferation. Am J Parhol 120:427—435, 1985 39. KASHGARIAN M: Mesangium and glomerular disease. Lab Invest 52:569—571, 1985 40. BOHRER MP, BAYLIS C, ROBERTSON CR, BRENNER BM: Mecha-

nisms of the puromycin induced defects in the transglomerular passage of water and macromolecules. J Gun Invest 60:152—161,

22. COUSER WG, STILMANT MM: Mesangial lesions and focal glomerular sclerosis in the aging rat. Lab Invest 33:491—501, 1975 23. NAKAMURA T, OITE T, SHIMIZU F, MATSUYAMA M, KAZAMA T,

1977 41. FoGo A, YOSHIDA Y, KIKUCHI T, GLICK A, ICHIKAWA I: Serial

KODA Y, ARAKAWA M: Sclerotic lesions in the glomeruli of

rnicropuncture analysis of the same nephrons in chronic renal

Buffalo/Mna rats. Nephron 43:50—55, 1986 24. ELEMA JD, KOUDSTAAL J, LAMBERTS HB, ARENDS A: Spontane-

diseases (CRD): Studies in two rat models of glomerular sclerosis (US). (abstract) Kidney Int 31:384, 1987

ous glomerulosclerosis in the rat. Effect of nephrectomy and

42. HOYER JR. ELEMA JD, VERNIER RL: Unilateral renal disease in the

irradiation of the contralateral kidney. Arch Pathol 91:418—425,

rat. II. Glomerular mesangial uptake of colloidal carbon in unilateral aminonucleoside nephrosis and nephrotoxic serum nephritis.

1971

25. KREISBERG fl, KARNOVSKY MJ: Focal glomerular sclerosis in the Fawn-Hooded rat. Am J Pathol 92:637—645, 1978 26. ERICSSON JLE, ANDRES GA: Electron microscopic studies on the development of the glomerular lesions in aminonucleoside nephrosis. Am J Pathol 39:643—663, 1961 27. GLASSER Ri, VELOSA JA, MICHAEL AF: Experimental model of

focal sclerosis. I. Relationship to protein excretion in aminonucleoside nephrosis. Lab Invest 36:519—526, 1977 28. LALICH JJ, FAITH GC, HARDING GE: Protein overload nephropathy. Arch Pathol 89:548—554, 1970 29. KLEINKNECHT C, SALUSKY I, BROYER M, GUBLER MC: Effects of

Lab Invest 34:250—255, 1976 43. MAUER SM, FISH AJ, DAY NK, MICHAEL AF: The glomerular mesangium. II. Studies of macromolecular uptake in nephro(oxic nephritis in rats. J Glin Invest 53:431—439, 1974 44. SCHNEEBERGER EE, COLLINS AB, LATTA H, MC CLUSKEY RT:

Diminished glomerular accumulation of colloidal carbon in autologous immune complex nephritis. Lab Invest 37:9—19, 1977 45. SCHNEEBERGER EE, COLLINS AB, STRAVRAKIS G, MC CLUSKEY

RT: Diminished mesangial accumulation of intravenously injected soluble immune complexes in rats with autologous immune complex nephritis. Lab Invest 42:440—449, 1980