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Results for “DIETARY PROTEINS”

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PubMed1997

Tissue-specific effects of chronic dietary protein restriction and gastrostomy on the insulin-like growth factor-I pathway in the liver and colon of adult rats.

Dietary protein restriction decreases plasma concentrations of insulin-like growth factor-I (IGF-I) and reduces IGF-I mRNA levels in the liver. In addition to the actions of systemic IGF-I, locally produced IGF-I is thought to mediate autocrine and paracrine growth effects in the colon. The objectives of the present study were to investigate the IGF-I pathway in the colon and liver of adult rats under conditions of dietary protein restriction, surgical stress, and dietary protein repletion. Two groups of rats were placed on either a 20% or 2% casein diet for 19 days. Two additional groups of rats underwent gastrostomy after a 2% casein diet for 2 weeks, and then were either kept on the 2% casein diet or changed to a 20% casein diet until day 19. Dietary protein restriction reduced plasma concentrations of IGF-I and IGF-binding proteins (IGFBPs) and hepatic IGF-I mRNA content, while increasing colonic IGF-I receptor mRNA. Gastrostomy in protein-depleted animals had no effect on hepatic IGF-I mRNA, but led to a marked increase in colonic IGF-I mRNA levels. Dietary protein repletion resulted in a decrease in colonic IGF-I receptor mRNA. The distinct effects of dietary protein depletion and operative stress on the IGF pathway in the colon as compared with the liver may serve to maintain the level of IGF-I signaling in the colon by autocrine or paracrine mechanisms under these conditions.

Animals↗

PubMed1992

Dietary protein intake is not correlated with clinical proteinuria in NIDDM.

OBJECTIVE: To determine whether dietary protein intake is correlated with clinical proteinuria in subjects with non-insulin-dependent diabetes mellitus (NIDDM). RESEARCH DESIGN AND METHODS: Cross-sectional analysis of data obtained from the San Antonio Heart Study, a population-based survey of diabetes and cardiovascular risk factors. Subjects were enrolled in two phases: phase 1 between 1979 and 1982 and phase 2 between 1984 and 1988. This study was based on 376 NIDDM subjects who had both urinalysis and complete dietary protein intake information available. Dietary protein intake was measured by 24-h dietary recall in phase 1 and by food-frequency questionnaire in phase 2. An early-morning spot urine was obtained from study subjects. Clinical proteinuria was defined as greater than or equal to 1 on Ames Albustix test. RESULTS: In phase 1, the subjects with negative or trace proteinuria had a mean protein intake of 79.9 g/day compared with 72.1 g/day for subjects with greater than or equal to 1 proteinuria. In phase 2, the mean protein intake was 72.2 g/day in the negative/trace group and 65.3 g/day in the greater than or equal to 1 proteinuria group. In multivariate analysis, adjusting for age, sex, ethnicity, systolic blood pressure, and 2-h blood glucose, we were again unable to detect a significant correlation between dietary protein intake and clinical proteinuria. CONCLUSIONS: These data do not support the hypothesis that high-protein intake is a risk factor for clinical proteinuria in NIDDM subjects. Therefore, any recommendation for protein restriction in the diets of NIDDM subjects, before the development of NIDDM-related nephropathy, must be made with caution.

Adult↗

PubMed2002

Effects of dietary protein and oathull fiber on nitrogen excretion patterns and postprandial plasma urea profiles in grower pigs.

The objectives of this study were: 1) to determine if dietary protein reduction or oathull fiber inclusion would reduce urinary N excretion in grower pigs, 2) to determine if plasma urea could predict urinary N excretion among diets differing in protein and fiber content with an expected range in N excretion patterns, and 3) to determine the postprandial time point to sample blood for the best prediction. Three dietary protein concentrations (high, 19.7; medium, 16.9; low, 13.8%) and two fiber levels (high, 5.0; low, 3.6% crude fiber) were tested in a 3 x 2 factorial arrangement. Diets (wheat, barley, soybean meal; oathulls as fiber source) were formulated to 3.25 Mcal of digestible energy (DE)/kg and 2.2 g of digestible lysine/Mcal DE for low- and medium-protein diets, and 2.4 g/Mcal of DE for high-protein diets, and supplemented with lysine, methionine, tryptophan, threonine, isoleucine, or valine to meet an ideal amino acid profile. Pigs (32 +/- 3.4 kg; n = 42) were housed in metabolism crates for 19 d. On d 10 or 11, catheters were installed by cranial vena cava venipuncture. Daily feeding allowance was adjusted to 3x maintenance (3 x 110 kcal DE/kg body weight(0.75)), and was fed in two equal meals. Feces and urine were collected from d 15 to 19. Five blood samples were collected in 2-h intervals on d 16 and 19. Fecal, urinary, and total N excretion was reduced linearly with a reduction of dietary protein (P < 0.001); the reduction was greater for urinary (48%) and total N excretion (40%) than for fecal N excretion (23%). Similarly, the ratio of urinary to fecal N was reduced linearly with a reduction of dietary protein (P < 0.001). Retention of N (g/d) was reduced linearly, but N retention as a percentage of N intake was increased linearly with a reduction of dietary protein (P < 0.001). The addition of oathulls did not affect N excretion patterns and plasma urea (P > 0.10). Dietary treatments did not affect average daily gain or feed efficiency (P > 0.10). A dietary protein x time interaction affected plasma urea (P < 0.001). For medium- and high-protein diets, plasma urea increased postprandially, peaking 4 h after feeding, and then decreased toward preprandial levels (P < 0.05). Plasma urea did not alter postprandially for the low-protein diet (P > 0.10). Urinary N excretion (g/d) was predicted by 3.03 + 2.14 x plasma urea concentration (mmol/L) at 4 h after feeding (R2 = 0.66). Plasma urea concentration is indicative of daily urinary N excretion and reduction of dietary protein is effective to reduce total and urinary N excretion.

Animals↗

PubMed2004

Response of hepatic proteins to the lowering of habitual dietary protein to the recommended safe level of intake.

The plasma concentrations of albumin, HDL apolipoprotein A1 (apoA1), retinol-binding protein (RBP), transthyretin (TTR), haptoglobulin, and fibrinogen were measured, and a stable isotope infusion protocol was used to determine the fractional and absolute synthesis rates of RBP, TTR, and fibrinogen in 12 young adults on three occasions during a reduction of their habitual protein intake from 1.13 to 0.75 g x kg(-1) x day(-1) for 10 days. This study was performed to determine whether healthy adults could maintain the rates of synthesis of selected nutrient transport and positive acute-phase proteins when consuming a protein intake of 0.75 g x kg(-1) x day(-1). During the lower protein intake, the plasma concentration of all the proteins, other than HDL-apoA1, remained unchanged. HDL-apoA1 concentration was significantly reduced (P < 0.05) after 3 days of the lower protein intake, but not at 10 days. The rates of synthesis of RBP and TTR declined significantly (P < 0.05), whereas the rate of synthesis of fibrinogen remained unchanged. The results indicate that, when normal adults consume the recommended safe level of protein, 0.75 g x kg(-1) x day(-1), there is a slower rate of turnover of nutrient transport proteins than on their habitual diet. Hence, healthy individuals consuming this amount of protein may be less able to mount an adequate metabolic response to a stressful stimulus.

Acute-Phase Proteins↗

PubMed1986

IgG subclass of human serum antibodies reactive with dietary proteins.

Serum IgG antibodies reactive with different dietary proteins have been detected in a significant proportion of adult patients with coeliac disease, dermatitis herpetiformis and atopic eczema. Serum anti-milk antibodies were shown to be distributed predominantly between the IgG2 and IgG4 subclasses, whereas anti-gliadin antibodies in atopic eczema were predominantly of the IgG4 subclass. Furthermore, as antibodies to each of these dietary antigens in healthy adults were markedly restricted to the IgG4 subclass, their production may be part of a normal immune response to dietary proteins. There was no correlation between serum IgG4 antibody and total serum IgG4 level. In contrast, restricted IgG4 anti-gliadin antibodies were less prevalent in the serum of patients with coeliac disease and dermatitis herpetiformis, suggesting defective downstream switching of Ig heavy-chain genes in these conditions.

Celiac Disease↗

PubMed1990

Effect of dietary protein on the renin-angiotensin system in subtotally nephrectomized rats.

Dietary protein restriction improves the course of renal disease in the remnant kidney model. Dietary protein restriction can also reduce plasma renin activity in several circumstances. We examined the interaction between dietary protein and the renin-angiotensin system in subtotally nephrectomized rats (1-2/3 nephrectomy). No difference was seen in tissue renin activity in rats ingesting a high (30%) versus a low (6%) protein diet. To determine the pathophysiological role of angiotensin II in subtotally nephrectomized rats, we examined the acute renal response to an intrarenal infusion of the angiotensin II antagonist Sar1 Gly8-angiotensin II (10 micrograms/kg/min). Only those subtotally nephrectomized animals ingesting a high protein diet exhibited a consistent improvement in glomerular permselectivity, as manifested by a 24% fall in the fractional clearance of albumin (basal 16.19 +/- 3.65 x 10(-4) vs. Sar1 Gly8-AII 12.26 +/- 3.21 x 10(-4); P less than 0.02) and a 19% fall in the fractional clearance of IgG (basal 3.75 +/- 0.67 x 10(-4) vs. Sar1 Gly8-AII 3.03 +/- 0.48 x 10(-4); P less than 0.02). No consistent change occurred in glomerular permselectivity in the rats on the low protein diet or rats infused with vehicle only. No change in mean arterial pressure or whole-kidney hemodynamics were seen with angiotensin II blockade. Decrements in SNGFR and glomerular capillary pressure occurred with angiotensin blockade in the animals ingesting the high protein diet, suggesting hemodynamic factors as a mechanism for the improvement in permselective defects.(ABSTRACT TRUNCATED AT 250 WORDS)

Angiotensin II↗

PubMed2005

Increased endothelin activity mediates augmented distal nephron acidification induced by dietary protein.

We tested the hypothesis that increased dietary protein augments distal nephron acidification through an endothelin-dependent mechanism. Munich-Wistar rats ate minimum electrolyte diets of 50% (HiPro) and 20% (CON) casein-provided protein, the latter comparable to standard chow. HiPro vs. CON had higher distal nephron H+ secretion (41.3 +/- 4.0 vs. 23.0 +/- 2.1 pmol/mm.min, p < 0.002) mediated by augmented Na+/H+ exchange and H(+)-ATPase activity. Renal cortex of HiPro vs. CON had higher ET-1 addition to microdialysate and higher ET-1 mRNA, consistent with increased renal ET-1 production. Bosentan, an endothelin A/B receptor antagonist, decreased HiPro distal nephron H+ secretion (28.4 +/- 2.4 vs. 41.3 +/- 4.0 pmol/mm.min, p < 0.016) through decreased Na+/H+ exchange and decreased H(+)-ATPase activity. Increased dietary protein augments distal nephron acidification through an endothelin-sensitive increase in Na+/H+ exchange and H(+)-ATPase activity, supporting an endothelin role in the distal nephron response to this common challenge to acid-base status.

Acid-Base Equilibrium↗

PubMed2002

Energy and protein metabolism in pregnant sows fed two levels of dietary protein.

The present study was performed to quantify the energy and nutrient metabolism of pregnant sows fed high (HP) or low (LP) dietary protein [18.3 vs. 13.5% of dry matter (DM)]. A total of nine sows (four on HP and five on LP diet) were subjected to balance and respiration trials four times during their second pregnancy (approximately on days 30, 61, 80 and 104 of gestation). The digestibility of protein (83.0 vs. 79.9) (p < 0.01) and energy (84.9 vs. 83.7%) (p < 0.05) was higher for the HP diet. Daily intake of metabolizable energy (ME) and retained energy (RE) were similar for the two groups, with an average of 28.37 MJ ME and 3.94 MJ RE, respectively. Heat production (HE) measured according to the respiratory quotient (RQ) and carbon-nitrogen (CN) method was similar (464 vs. 454 kJ/kg 0.75/day, respectively). Sows fed HP retained more energy in protein (3.33 vs. 2.00 MJ/day) (p < 0.001) and tended to retain less energy in fat (1.59 vs. 2.50 MJ/day) than LP sows. Retained nitrogen (N) (22.3 vs. 13.4 g/day) (p < 0.001) and utilization of N (retained/digested) (45.2 vs. 38.1%) was higher for HP sows compared with LP sows. In late pregnancy, retained N, retained fat, HE and oxidation of carbohydrates increased, while oxidation of fat was reduced to zero. In conclusion, both diets provided adequate N for retention in maternal tissue and conception products. In spite of the lower utilization of N in LP sows, the N excretion was depressed by 5.6 g/day compared with HP sows, because of the lower N intake.

Animals↗

PubMed1998

Tissue specific-distribution and metabolism of vitamin A are affected by dietary protein levels in rats.

The effect of dietary protein levels on tissue-specific distribution and metabolism of vitamin A was studied in rats given [15-14C] retinol (14C-ROH). The weanling rats were fed a low level vitamin A diet for 10 days, then rats (15 rats per group) were divided into 2 groups; one was given a 40% casein diet as a high protein diet (HP-diet), and the other a 5% casein diet as a low protein diet (LP-diet). After 10 days feeding on these diets, 14C-ROH (5 microCi/rat) was given to both groups, HP-diet and LP-diet, by intraperitoneal injection. The radioactivity in the exhalated gases, urine and feces was measured to estimate the rate of vitamin A metabolism. The tissue specific-distribution of ROH was studied in terms of the radioactivities of the ROH fractions separated by HPLC. The hepatic 14C-ROH content in the HP-diet group was lower than that in the LP-diet group at 24, 48, and 72 hours after administration of 14C-ROH. In contrast, 14C-ROH content in serum, spleen, pancreas, and small intestinal mucosa in the HP-diet group was higher than that in the LP-diet group. The radioactivity of the exhalated gas and feces was higher in the HP-diet group. These results suggest that metabolism of vitamin A is higher with intake of a HP-diet. Thus, dietary protein levels may affect tissue-specific distribution and metabolism of vitamin A, thereby modulating the actions of this vitamin.

Animals↗

PubMed1998

Effect of dietary protein on translation initiation in rat skeletal muscle and liver.

The effect of dietary protein on the initiation of mRNA translation was examined in rats starved for 18 h and then fed isocaloric diets containing either 20% protein (20P) or no added protein (0P). Feeding the 20P diet, but not the 0P diet, stimulated protein synthesis in skeletal muscle and liver by 38 and 41%, respectively. The stimulation was associated with reduced binding of eukaryotic initiation factor (eIF) 4E to the translational repressor 4E-BP1, increased formation of the active eIF4E-eIF4G complex, and increased phosphorylation of 4E-BP1. In contrast, feeding a 0P diet had no effect on any of these parameters. Feeding a 20P diet resulted in partial dephosphorylation of eIF4E in both tissues. In liver, refeeding a 0P diet also resulted in partial eIF4E dephosphorylation, suggesting that the phosphorylation state of eIF4E is not important in the stimulation of protein synthesis under these conditions. Finally, plasma insulin concentrations were the same in rats fed either diet (14.8 +/- 4.9 vs. 15.5 +/- 4.5 microU/ml for 20P and 0P groups, respectively), suggesting that feeding-induced changes in plasma insulin are not sufficient to stimulate protein synthesis. Instead, a combination of dietary protein and insulin may be required to stimulate translation initiation.

Animals↗

PubMed1984

The role of dietary protein in the progression and symptomatology of chronic renal failure.

Dietary factors may have substantial impact on the clinical manifestations and even the progression of chronic renal failure. Proper dietary management can prevent certain uremic complications, decrease azotemia, and may even prevent the loss of residual renal function. Recent studies indicate that dietary protein may accelerate the normal age-related deterioration of renal function in rats. The extensive ablation of functional renal mass in rats leads to hyperemia and hyperfiltration in remnant nephrons. Continued hyperfiltration theoretically results in glomerular damage, proteinuria, and ultimately glomerular sclerosis. Dietary protein restriction reduces the remnant nephron hyperfiltration and reduces the rate of glomerular sclerosis, at least in the rat. The role of dietary protein in the pathogenesis of human nephrosclerosis remains controversial. Though dietary factors may or may not affect the rate of progression of renal insufficiency, there is no doubt that proper dietary management can limit or forestall uremic symptoms and the need for dialysis. Diets containing about 0.5 gm protein/kg body weight/day usually maintain a neutral or slightly positive nitrogen balance, while lesser amounts usually result in malnutrition. When protein intake exceeds 0.5 gm/kg/day azotemia increases dramatically. The use of nitrogen-free keto- or hydroxy-analogues of amino acids promotes positive nitrogen balance while reducing azotemia in patients with near-end-stage renal disease.

Amino Acids↗

PubMed2001

Influence of dietary protein levels on beta-alanine aminotransferase expression and activity in rats.

beta-Alanine-oxoglutarate aminotransferase (beta-AlaAT I) and beta-alanine-pyruvate aminotransferase (beta-AlaAT II) catalyze the transamination reaction of omega-amino acids such as beta-alanine, beta-aminoisobutyrate, and gamma-aminobutyrate, amino acids that are not protein constituents. The influence of dietary protein levels on the expression and activities of these enzymes was investigated by using male rats. Both beta-AlaAT I and beta-AlaAT II activities in the liver were increased with the level of protein in the diet in accordance with changes in their mRNA levels. However, the beta-AlaAT I activity in the kidney was increased by protein-free and low-protein diets in relation to changes in its mRNA level. On the other hand, the level of beta-AlaAT II activity in the kidney was slightly decreased by a protein-free diet. Neither beta-AlaAT I nor beta-AlaAT II activities in the kidney were affected by a high-protein diet. These results suggested that beta-alanine may be used efficiently in animals fed a proteinfree or low-protein diet because the kidney provides beta-alanine by means of the hydrolysis of beta-alanyl-L-histidine (carnosine). The addition of beta-alanine to the diet significantly activated beta-AlaAT I in the kidneys of rats in accordance with changes in its mRNA level. In the rat brain, beta-AlaAT I activity was not altered by the dietary protein level or by the beta-alanine diet, and beta-AlaAT II activity was not detected.

Alanine Transaminase↗

PubMed1984

Adaptation of Na+-H+ exchange in renal microvillus membrane vesicles. Role of dietary protein and uninephrectomy.

The ablation of renal mass and institution of a high protein diet both lead to renal cortical hypertrophy and increased glomerular filtration rate (GFR). We studied Na+ transport in rat microvillus membrane vesicles isolated from uninephrectomized or sham operated rats fed 6% (low), 24% (standard), or 40% (high) protein diets. The feeding of high protein, as compared with low protein, was associated with a 50% increase in rates of pH-stimulated 22Na+ transport in isolated vesicles from sham and uninephrectomized animals. Values for the standard protein diet were intermediate to values for high and low protein. At each level of dietary protein intake, vesicular Na+ transport was greater in the uninephrectomized than in sham rats. The high protein diet was also associated with increased vesicular 22Na+ flux inhibitable by 1 mM amiloride. Increases in total and amiloride sensitive flux were also noted in the absence of a pH gradient. Conductive Na+ and H+ transport were not altered, nor were sodium-glucose and sodium-alanine cotransport. Kinetic studies revealed evidence for an increased Vmax of Na+-H+ exchange in uninephrectomized animals fed a 40 vs. a 6% protein diet whereas Km was unchanged. Supplements of NaHCO3 in the 40% protein diet, to adjust for an increased rate of net acid excretion, did not prevent the increased rates of Na+-H+ exchange. However, treatment with actinomycin D (0.12 mg/kg) prevented the increased Na+-H+ activity as well as the increased renal mass and GFR noted 24 h after unilateral nephrectomy. Na+-H+ exchange rate was closely correlated with GFR (r = 0.961; P less than 0.005) and renal mass (r = .986; P less than 0.001). These observations provide evidence for modification of the luminal membrane Na+-H+ exchanger in response to changes in dietary protein content and nephron number.

Animals↗

PubMed1991

Research note: adding coefficients for dietary protein and energy to equations for predicting the metabolizable energy intake of laying hens.

The data from two published experiments were used to determine whether feed consumption prediction equations could be improved by the addition of coefficients for levels of protein and energy in the diet. The two experiments were conducted from 20 to 44 wk of age with hens housed in cages. Diets contained primarily corn, dehulled soybean meal, wheat middlings, and poultry oil. When the standard form of feed consumption prediction equations was fitted to the data, only the coefficient for egg mass (b3) was different from zero (P less than .10): MEI = b0 + b1 BWn + b2 delta g + b3 EM where MEI = metabolizable energy intake; BW = average body weight (kilograms), delta g = daily body weight change (grams); n = .65, .75, 1, or 2; and EM = daily egg mass output in grams. Three published equations that have been used to predict feed intake based on body weight and egg mass output were chosen for evaluation. For two equations the residual MEI (observed-predicted) was found to be predictable from protein or energy levels fed. Inserting dietary protein and dietary energy data for the feed decreased the observed error in equations to predict MEI, but the effect was small.

Animal Feed↗

PubMed1993

The importance of dietary protein in healing pressure ulcers.

OBJECTIVE: To determine the effect of dietary protein on healing of pressure ulcers in malnourished patients. DESIGN: Nutritional intervention trial with the non-randomized assignment of patients by pressure ulcer stage and bed type. SETTING: Long-term care facility. PATIENTS: Twenty-eight malnourished patients (age = 72 +/- 18 years, mean +/- SD) with a total of 33 truncal pressure ulcers. Nine patients had stage II ulcers, eight had stage III ulcers, and 16 had stage IV ulcers. METHODS: Patients received liquid nutritional formulas as tubefeedings or meal supplements containing either 24% protein (61 g protein/L; n = 15) or 14% protein (37 g protein/L; n = 13) for 8 weeks. RESULTS: There was a significant decrease in total truncal pressure ulcer surface area of the 15 patients in the 24% protein group (-4.2 +/- 7.1 cm2, P < 0.02), but not in the 13 patients in the 14% protein group (-2.1 +/- 11.5 cm2, P = NS). The change in total ulcer area correlated with both dietary protein intake per kg body weight (rs = -0.50, P < 0.01) and caloric intake per kg body weight (rs = -0.41, P < 0.03). The decrease in stage IV ulcer area in eight patients in the 24% protein group (-7.6 +/- 5.8 cm2, P < 0.02) was significantly greater (P < 0.05) than in eight patients in the 14% protein group (-3.2 +/- 16.4, P = NS). In these 16 patients, the decrease in ulcer size also correlated with dietary protein intake per kg body weight (rs = -0.63, P < 0.01). CONCLUSION: High protein diets may improve the healing of pressure ulcers in malnourished nursing home patients.

Aged↗

PubMed1996

What role does dietary protein restriction play in the management of chronic renal failure in dogs?

Dietary protein restriction has been the mainstay of conservative medical management of canine renal failure for many years. Although dietary protein restriction minimizes many signs of uremia, its potential benefits to the progression of renal failure are now being questioned. Two case scenarios of different degrees of renal failure are described; guidelines for dietary protein restriction are based on currently available scientific knowledge.

Animals↗

PubMed2004

Evaluation of the immunogenicity of dietary proteins in cats and the influence of the canning process.

OBJECTIVE: To characterize the antigen-specific immune response to dietary proteins in cats and evaluate whether there was a qualitative or quantitative difference between the responses to dietary proteins when those proteins were fed unprocessed or as part of a canned diet. ANIMALS: 14 healthy domestic shorthair cats. PROCEDURE: Cats were fed 2 dietary proteins (soy and casein) either as unprocessed aqueous suspensions or as part of canned diets for 21 days. Serum IgG and IgA and salivary IgA were assayed by indirect ELISA, and antigen-specific proliferation of mesenteric lymph node-derived lymphocytes was determined. RESULTS: Robust serum IgG and IgA responses to dietary proteins were elicited, irrespective of the form in which they were fed. Salivary IgA responses to unprocessed proteins were not detected. However, a significant salivary IgA response to the protein isolated from the canned casein diet was observed in cats fed canned casein but not in those fed unprocessed casein. Lymphocyte proliferation to the antigens was slight, and there were no significant differences between groups. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that cats develop robust serum IgG and IgA responses to dietary proteins when fed as either aqueous suspensions or as part of canned diets. For certain proteins, there may be an increase and a qualitative difference in the immunogenicity of canned diets, compared with unprocessed proteins. Canned diets may not be ideal for management of cats with enteritis.

Animal Feed↗

PubMed1983

Amelioration of experimental glomerulonephritis by dietary protein restriction.

We have examined the effects of various levels of dietary protein intake on the course of nephrotoxic serum nephritis in the rat by feeding low (4.6% casein), standard (23% casein), and high (57.5% casein) protein diets which were identical in calorie, mineral, and electrolyte content. Nephritic rats on a high protein diet manifested heavy proteinuria, hypoalbuminemia, hypercholesterolemia, azotemia, and elevated serum creatinine levels. In those subjected to dietary protein restriction, proteinuria remitted and azotemia did not develop. While mesangial widening, interstitial abnormalities, and segmental proliferation and sclerosis of glomeruli occurred regularly in nephritic rats fed high protein diets, histologic abnormalities were virtually absent in those on low protein intake. Animals on a standard protein intake manifested histologic and clinical features intermediate in severity. We conclude that the renal functional and histologic consequences of nephrotoxic serum nephritis can be averted by dietary protein restriction.

Animals↗