Physiological and morphological responses of the rat kidney to reduced dietary protein

1985 ◽  
Vol 248 (1) ◽  
pp. F31-F42
Author(s):  
B. Schmidt-Nielsen ◽  
J. M. Barrett ◽  
B. Graves ◽  
B. Crossley
Keyword(s):  
Dietary Protein ◽  
Morphological Changes ◽  
Rat Kidney ◽  
Light And Electron Microscopy ◽  
Protein Diet ◽  
Free Access ◽  
Vascular Bundles ◽  
Urea Clearance ◽  
Morphological Studies ◽  
Additional Group

Renal physiological and morphological adjustments to a reduced protein diet were studied in young Munich-Wistar rats. Two groups of animals were used for the correlative physiological-morphological studies: normal protein (NP, 24% dietary protein) rats and reduced protein (LP, 8% dietary protein) rats. Both groups were fed their respective diets for 4-5 wk and had free access to drinking water. Physiological measurements of GFR and urea clearance were made on five animals from each group. These data showed that the changes in renal function specifically and almost exclusively affected the handling of urea. There was no difference in GFR between the NP and LP rats. Urea clearance was substantially reduced in LP rats. Morphological analyses were made on perfusion-fixed kidneys of five animals from each group. Selected slices were examined and photographed by light and electron microscopy. These data showed no difference in size and number of elements within the vascular bundles but showed significantly smaller lumina of the thin limbs of the short-looped nephrons and a significant thinning of the wall of the thin descending limbs of the long-looped nephrons. These morphological changes may in part be responsible for the observed physiological adjustments to a reduced protein diet. An additional group of rats (6 NP and 5 LP, all dehydrated) were analyzed for distribution of solutes within the inner medulla. The data showed that the concentration of urea, but not that of Na+, was reduced at the papillary tip in LP rats.

scholarly journals A histochemical approach to the mechanism of action of cisplatin and its analogues.

1993 ◽  
Vol 41 (7) ◽  
pp. 1053-1073 ◽  
Author(s):  
S K Aggarwal
Keyword(s):  
Membrane Transport ◽  
Mechanism Of Action ◽  
Morphological Changes ◽  
Calcium Supplementation ◽  
Rat Kidney ◽  
Light And Electron Microscopy ◽  
Atp Synthesis ◽  
Chloride Ion ◽  
Tissue Homogenates ◽  
Cancer Agent

The effects of cisplatin (CDDP), a potent anti-cancer agent, and its various analogues were analyzed for any biochemical changes involving Ca2+ and lysosomal and membrane-associated transport enzymes in rat kidney, liver, serum, urine, tissue homogenates, and isolated mitochondria. Correlation was made with any morphological changes observed by light and electron microscopy to gain an insight into the mechanism of action of various platinum coordination complexes. CDDP in its hydrolyzed state under conditions of low chloride ion concentrations causes uncoupling of oxidative phosphorylation, calcium efflux from the mitochondria, inhibits ATP synthesis, lowers membrane-associated calcium and various membrane transport enzymes, and induces an increase in the number of lysosomes. Enzymes such as alkaline phosphatase are stripped from the brush borders of the proximal tubule cells and are discharged in the urine. However, daily IV injections of calcium (1.1 ml of 1.3% CaCl2) supplementation protect the membrane-associated enzymes from cisplatin action. Carboplatin (CBDCA), an analogue of CDDP and the least nephrotoxic of all its analogues, shows little effect on the membrane-associated transport enzymes. Therefore, cisplatin and its various analogues seem to affect the membrane transport enzymes to varying degrees with related nephrotoxicity. Calcium supplementation seems to protect these enzymes and preserve kidney function.

Electron microscopic study of the membrane glycoproteins in the rat kidney after cisplatin treatment

1989 ◽  
Vol 47 ◽  
pp. 912-913
Author(s):  
S.K. Aggarwal
Keyword(s):  
Alkaline Phosphatase ◽  
Rat Kidney ◽  
Light And Electron Microscopy ◽  
Kidney Tissue ◽  
Membrane Glycoproteins ◽  
Electron Microscopic ◽  
Before And After ◽  
Interstrand Cross Links ◽  
Cross Links

The proposed primary mechanism of action of the anticancer drug cisplatin (Cis-DDP) is through its interaction with DNA, mostly through DNA intrastrand cross-links or DNA interstrand cross-links. DNA repair mechanisms can circumvent this arrest thus permitting replication and transcription to proceed. Various membrane transport enzymes have also been demonstrated to be effected by cisplatin. Glycoprotein alkaline phosphatase was looked at in the proximal tubule cells before and after cisplatin both in vivo and in vitro for its inactivation or its removal from the membrane using light and electron microscopy.Outbred male Swiss Webster (Crl: (WI) BR) rats weighing 150-250g were given ip injections of cisplatin (7mg/kg). Animals were killed on day 3 and day 5. Thick slices (20-50.um) of kidney tissue from treated and untreated animals were fixed in 1% buffered glutaraldehyde and 1% formaldehyde (0.05 M cacodylate buffer, pH 7.3) for 30 min at 4°C. Alkaline phosphatase activity and carbohydrates were demonstrated according to methods described earlier.

PROTECTIVE EFFECT OF SOME SALTS 2-AMINOETHANESULFONIC ACID IN AN EXPERIMENTAL MODEL OF DEGENERATIVE SPINAL CORD INJURY

2020 ◽  
pp. 41-47
Author(s):  
Semeleva E.V. ◽  
Blinova E.V. ◽  
Zaborovsky A.V. ◽  
Vasilkina O.V. ◽  
Shukurov A.S.
Keyword(s):  
Spinal Cord ◽  
Morphological Changes ◽  
Male Rats ◽  
Zinc Salt ◽  
Control Group ◽  
Morphological Studies ◽  
Cord Injury ◽  
The Central Nervous System ◽  
Acid Compound ◽  
Lateral Sclerosis

In this work, we studied the pharmacological activity of zinc and magnesium salts of 2-aminoethanesulfonic acid in white non-linear male rats with amyotrophic lateral sclerosis, which was modeled by neurotoxicantsimplication into the pelvic part of spinal cord. After the reproduction of the pathology in animals, the indices of motor activity were recorded in the Rotarod test, and morphological studies of spinal cord sections stained according to Nisl in the Belshovsky modification were carried out. It was shown that the magnesium salt of 2-aminoethanesulfonic acid (compound LHT-317) to a greater extent reduces the development of motor disorders in experimental animals compared with the control group on the 4th day of observation. The course of intravenous administration of the studied compounds of 2-aminoethanesulfonic acid did not inhibit morphological changes in the spinal cord that develop in degenerative-dystrophic pathology of the central nervous system: connections. Moreover, if, against the background of treatment with zinc salt, the total area of motor zones in animals of the experimental group exceeded that of control rats, then the number of motoneurons did not differ from the control.

scholarly journals Severe protein deficiency induces hepatic expression and systemic level of FGF21 but inhibits its hypothalamic expression in growing rats

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Joanna Moro ◽  
Catherine Chaumontet ◽  
Patrick C. Even ◽  
Anne Blais ◽  
Julien Piedcoq ◽  
...  
Keyword(s):  
Body Weight ◽  
Food Intake ◽  
Energy Expenditure ◽  
Energy Intake ◽  
Dietary Protein ◽  
Protein Deficiency ◽  
Protein Diet ◽  
Growing Rats ◽  
Low Protein ◽  
Protein Diets

AbstractTo study, in young growing rats, the consequences of different levels of dietary protein deficiency on food intake, body weight, body composition, and energy balance and to assess the role of FGF21 in the adaptation to a low protein diet. Thirty-six weanling rats were fed diets containing 3%, 5%, 8%, 12%, 15% and 20% protein for three weeks. Body weight, food intake, energy expenditure and metabolic parameters were followed throughout this period. The very low-protein diets (3% and 5%) induced a large decrease in body weight gain and an increase in energy intake relative to body mass. No gain in fat mass was observed because energy expenditure increased in proportion to energy intake. As expected, Fgf21 expression in the liver and plasma FGF21 increased with low-protein diets, but Fgf21 expression in the hypothalamus decreased. Under low protein diets (3% and 5%), the increase in liver Fgf21 and the decrease of Fgf21 in the hypothalamus induced an increase in energy expenditure and the decrease in the satiety signal responsible for hyperphagia. Our results highlight that when dietary protein decreases below 8%, the liver detects the low protein diet and responds by activating synthesis and secretion of FGF21 in order to activate an endocrine signal that induces metabolic adaptation. The hypothalamus, in comparison, responds to protein deficiency when dietary protein decreases below 5%.

Functional alterations in the rat kidney induced either by diabetes or high protein diet

2009 ◽  
Vol 105 (S 02) ◽  
pp. 48-50 ◽  
Author(s):  
A. Dunger ◽  
S. Berg ◽  
I. Klöting ◽  
S. Schmidt
Keyword(s):  
Rat Kidney ◽  
High Protein Diet ◽  
High Protein ◽  
Protein Diet

scholarly journals The effect of dietary protein on reproduction in the mare. VI. Serum progestagen concentrations during pregnancy

1998 ◽  
Vol 69 (4) ◽  
Author(s):  
F.E. Van Niekerk ◽  
C.H. Van Niekerk
Keyword(s):  
Dietary Protein ◽  
Protein Quality ◽  
Amino Acid Content ◽  
Protein Supplementation ◽  
The Other ◽  
Protein Diet ◽  
Sharp Decline ◽  
High Quality Protein ◽  
Essential Amino Acid Content

Sixty-four Thoroughbred and Anglo-Arab mares aged 6-12 years were used, of which 40 were non-lactating and 24 lactating. Foals from these 24 mares were weaned at the age of 6 months. Non-lactating and lactating mares were divided into 4 dietary groups each. The total daily protein intake and the protein quality (essential amino-acid content) differed in the 4 groups of non-lactating and 4 groups of lactating mares. The mares were covered and the effect of the quantity and quality of dietary protein on serum progestagen concentrations during pregnancy was studied. A sharp decline in serum progestagen concentrations was recorded in all dietary groups from Days 18 to 40 of pregnancy, with some individual mares reaching values of less than 4 ng/mℓ. Serum progestagen concentrations recorded in some of the non-lactating mares on the low-quality protein diet increased to higher values (p<0.05) than those of mares in the other 3 dietary groups at 35-140 days of pregnancy. A similar trend was observed for the lactating mares on a low-quality protein diet at 30-84 days of pregnancy. No such trends were observed in any of the other dietary groups. High-quality protein supplementation increased serum progestagen concentrations during the 1st 30 days of pregnancy. Lactation depressed serum progestagen concentrations until after the foals were weaned.

Morphological studies of bone and tendon

1992 ◽  
Vol 73 (2) ◽  
pp. S10-S13 ◽  
Author(s):  
S. B. Doty ◽  
E. R. Morey-Holton ◽  
G. N. Durnova ◽  
A. S. Kaplansky
Keyword(s):  
Electron Microscopy ◽  
Bone Cells ◽  
Weight Bearing ◽  
Light And Electron Microscopy ◽  
Cell Activity ◽  
Bone Cell ◽  
Electron Microscopic ◽  
Adult Rats ◽  
Morphological Studies ◽  
Metatarsal Bones

The Soviet biosatellite COSMOS 2044 carried adult rats on a spaceflight that lasted 13.8 days and was intended to repeat animal studies carried out on COSMOS 1887. Skeletal tissue and tendon from animals flown on COSMOS 2044 were studied by light and electron microscopy, histochemistry, and morphometric techniques. Studies were confined to the bone cells and vasculature from the weight-bearing tibias. Results indicated that vascular changes at the periosteal and subperiosteal region of the tibia were not apparent by light microscopy or histochemistry. However, electron microscopy indicated that vascular inclusions were present in bone samples from the flight animals. A unique combination of microscopy and histochemical techniques indicated that the endosteal osteoblasts from this same mid-diaphyseal region demonstrated a slight (but not statistically significant) reduction in bone cell activity. Electron-microscopic studies of the tendons from metatarsal bones showed a collagen fibril disorganization as a result of spaceflight. Thus changes described for COSMOS 1887 were present in COSMOS 2044, but the changes ascribed to spaceflight were not as evident.

EFFECTS OF GRADED DIETARY PROTEIN LEVELS ON UREA RECYCLING IN THE PIG

1982 ◽  
Vol 62 (4) ◽  
pp. 1193-1197 ◽  
Author(s):  
P. A. THACKER ◽  
J. P. BOWLAND ◽  
L. P. MILLIGAN ◽  
E. WELTZIEN
Keyword(s):  
Dietary Protein ◽  
Protein Diet ◽  
Nitrogen Excretion ◽  
Entry Rate ◽  
Protein Nitrogen ◽  
Protein Levels ◽  
Low Protein ◽  
Key Words Pig ◽  
Urea Recycling ◽  
Protein Diets

The kinetics of urea recycling were determined in six female crossbred pigs utilizing a radioisotope dilution technique. The experimental animals were fed three times daily 500 g of a corn-soybean meal diet formulated to contain 8.4, 15.8 or 24.7% crude protein. Nitrogen digestibility, urinary nitrogen excretion, total nitrogen excretion and retained nitrogen were highest on the 24.7% protein diet and decreased with decreasing dietary protein. Urea pool size, entry rate and excretion rate were also highest on the 24.7% protein diet and decreased with decreasing protein intake. Expressed as a percentage of the total entry rate, a significantly higher percentage of urea was recycled in pigs fed the low protein diets compared with those fed a higher protein diet. Key words: Pig, urea, recycling, kinetics, protein

scholarly journals Morphological changes in parenchymal organs of laboratory animals in acute effect of carbon tetrachloride

2020 ◽  
Vol 99 (9) ◽  
pp. 1001-1006
Author(s):  
Elvira F. Repina ◽  
Denis O. Karimov ◽  
Samat S. Baygildin ◽  
Gulnara V. Timasheva ◽  
Nadezhda Yu. Khusnutdinova ◽  
...  
Keyword(s):  
Ascorbic Acid ◽  
Carbon Tetrachloride ◽  
Protective Effect ◽  
Morphological Changes ◽  
Acute Exposure ◽  
Laboratory Animals ◽  
Antihypoxic Activity ◽  
Prophylactic Administration ◽  
Morphological Studies ◽  
High Doses

Introduction. Among noninfectious diseases, one of the leading places belongs to pathologies caused by the action of industrial toxicants. In this regard, the search for drugs for the prevention and treatment of various intoxications is one of the priority tasks of public health. Treatment of intoxication with drugs with antioxidant and antihypoxic activity is more effective. The aim of this study was to investigate morphological changes in parenchymal organs (liver, kidneys, and pancreas) under acute exposure to high doses of carbon tetrachloride and to evaluate the effectiveness of their correction with a new composition of oxymethyluracil with ascorbic acid. Material and methods. The composition of 5-hydroxy-6-methyluracil with ascorbic acid was first synthesized at the Ufa Institute of Chemistry, Ufa Federal Research Center, RAS. The preventive effect of the new drug was studied in comparison with “Heptor” on the carbon tetrachloride-induced liver injury model. Morphological studies of the liver, pancreas, and kidneys of laboratory animals were carried out. Results. Studies have shown the prophylactic administration of new composition of 5-hydroxy-6-methyluracil with ascorbic acid to have a protective effect on the structure of parenchymal organs in acute carbon tetrachloride intoxication, comparable to the drug “Heptor” (possibly superior). However, reparative properties were observed only in the drug “Heptor”. Conclusion. Comparative estimation of morphological changes in parenchymal organs under acute exposure to high doses of carbon tetrachloride indicates the protective effect of prophylactic administration of the composition of 5-hydroxy-6-methyluracil with ascorbic acid, comparable to the drug “Heptor” (possibly superior).

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