scholarly journals Protein abundance of urea transporters and aquaporin 2 change differently in nephrotic pair-fed vs. non-pair-fed rats

2012 ◽  
Vol 302 (12) ◽  
pp. F1545-F1553 ◽  
Author(s):  
Raed N. Bou Matar ◽  
Bela Malik ◽  
Xiaonan H. Wang ◽  
Christopher F. Martin ◽  
Douglas C. Eaton ◽  
...  
Keyword(s):  
Urinary Sodium Excretion ◽  
Protein Abundance ◽  
Mrna Levels ◽  
Sprague Dawley ◽  
Tissue Samples ◽  
Aquaporin 2 ◽  
Urine Protein Excretion ◽  
Protein Excretion ◽  
Sprague Dawley Rats ◽  
Ad Libitum

Salt and water retention is a hallmark of nephrotic syndrome (NS). In this study, we test for changes in the abundance of urea transporters, aquaporin 2 (AQP2), Na-K-2Cl cotransporter 2 (NKCC2), and Na-Cl cotransporter (NCC), in non-pair-fed and pair-fed nephrotic animals. Doxorubicin-injected male Sprague-Dawley rats ( n = 10) were followed in metabolism cages. Urinary excretion of protein, sodium, and urea was measured periodically. Kidney inner medulla (IM), outer medulla, and cortex tissue samples were dissected and analyzed for mRNA and protein abundances. At 3 wk, all doxorubicin-treated rats developed features of NS, with a ninefold increase in urine protein excretion (from 144 ± 21 to 1,107 ± 165 mg/day; P < 0.001) and reduced urinary sodium excretion (from 0.17 to 0.12 meq/day; P < 0.001). Urine osmolalities were reduced in the nephrotic animals (1,057 ± 37, treatment vs. 1,754 ± 131, control). Unlike animals fed ad libitum, UT-A1 protein abundance was unchanged in nephrotic pair-fed rats. Glycosylated AQP2 was reduced in the IM base of both nephrotic groups. Abundances of NKCC2 and NCC were consistently reduced (71 ± 7 and 33 ± 13%, respectively) in both nephrotic pair-fed animals and animals fed ad libitum. In pair-fed nephrotic rats, we observed an increase in the cleaved form of membrane-bound γ-epithelial sodium channel (ENaC). However, α- and β-ENaC subunits were unaltered. NKCC2 and AQP2 mRNA levels were similar in treated vs. control rats. We conclude that dietary protein intake affects the response of medullary transport proteins to NS.

PLATELET ACTIVATING FACTOR (PAF) AS A MEDIATOR OF PROTEINURIA IN ISOLATED PERFUSED KIDNEY (IPK).

1987 ◽  
Author(s):  
F Delani ◽  
M Tagliaferri ◽  
D Macconi ◽  
C Lupini ◽  
N Perico ◽  
...  
Keyword(s):  
Platelet Activating Factor ◽  
Sprague Dawley ◽  
Cationic Protein ◽  
Glomerular Permeability ◽  
Urine Protein Excretion ◽  
Protein Excretion ◽  
Sprague Dawley Rats ◽  
Vehicle Injection ◽  
Stabilization Period ◽  
Krebs Henseleit Buffer

PAF amplifies tissue damage in glomerulonephritis and can promote proteinuria stimulating platelet and neutrophil cationic protein release. We used IPK to establish whether PAF directly causes proteinuria. Kidneys were isolated from male Sprague-Dawley rats and perfused at constant pressure (100 mmHg) in a closed circuit with a Krebs-Henseleit buffer containing glucose urea creatinine, BSA (1%), Ficoll 70 (3.5%) and amino acids. After 25 min stabilization period, a basal 10 min clearance period was followed by PAF (1.8 nM f.c. n = 6) or vehicle (n = 5) injection into the renal artery. As seen in the figure PAF but not vehicle significantly (p<0.01) increased urine protein excretion. No significant changes in GFR (as creatinine clearance) were observed after PAF or vehicle injection (Basal: 0.786 ± 0.075 PAF: 0.658 ± 0.070. Basal 0.653 ± 0.081, vehicle 0.639 ± 0.074 ml/min/g kidney). The data indicate that PAF may directly increase glomerular permeability to proteins.

Light and electron microscopic investigation of adenohypophyses of germfree, food-restricted, and germfree-food restricted aging, male lobund-wistar rats

1988 ◽  
Vol 46 ◽  
pp. 352-353
Author(s):  
G. Ilse ◽  
K. Kovacs ◽  
N. Ryan ◽  
T. Sano ◽  
L. Stefaneanu ◽  
...  
Keyword(s):  
Wistar Rats ◽  
Microscopic Investigation ◽  
Electron Microscopic Investigation ◽  
Aging Male ◽  
Sprague Dawley ◽  
Electron Microscopic ◽  
Sprague Dawley Rats ◽  
Old Rats ◽  
Ad Libitum ◽  
Microscopic Findings

Germfree state and food restriction have been shown to increase life span and delay tumor occurrence in rats. We report here the histologic, immunocytochemical and electron microscopic findings of adenohypophyses of aging, male Lobund-Wistar rats raised at Lobund Laboratories. In our previous study, the morphologic changes in the adenohypophyses of old rats have been extensively investigated by histology, immunocytochemistry and electron microscopy. Lactotroph adenomas were frequent in Long-Evans and Sprague-Dawley rats, whereas gonadotroph adenomas were frequent in Sprague-Dawley and Wistar rats.Male Lobund-Wistar rats were divided into four groups: 1) conventional, which were raised under normal non-germfree environment and received food ad libitum; 2) germfree-food ad libitum; 3) conventional environment-food restricted and 4) germfree-food restricted. The adenohypophyses were removed from 6-month-, 18-month- and 30-month-old rats. For light microscopy, adenohypophyses were fixed in formalin and embedded in paraffin.

Changes in rat mesentery interstitial matrix due to superfusate

1993 ◽  
Vol 265 (3) ◽  
pp. H852-H856 ◽  
Author(s):  
B. J. Barber ◽  
R. A. Babbitt ◽  
S. Dutta ◽  
S. Parameswaran
Keyword(s):  
Protein Content ◽  
Normal Saline ◽  
Protein Concentration ◽  
Matrix Protein ◽  
Protein Transport ◽  
Albumin Concentration ◽  
Sprague Dawley ◽  
Tissue Samples ◽  
Rat Mesentery ◽  
Sprague Dawley Rats

Animal preparations for microscopy often require a superfusate solution to cover surgically exposed tissue. There are few, if any, data concerning the effects of this solution on extravascular protein concentration and hydration. The effect of superfusion on mesenteric tissue in anesthetized male Sprague-Dawley rats was studied. Tissue samples were taken from nonsuperfused and superfused tissue and analyzed for hydration, albumin, and transferrin content. The mesenteric tissue interstitial matrix was rapidly altered by normal saline superfusate. After superfusion, there was a decrease (P < 0.01) in tissue albumin concentration from 1.17 +/- 0.27 to 0.10 +/- 0.08 g/dl (n = 9). Tissue hydration increased from 4.98 +/- 0.8 micrograms water/microgram dry wt in controls to 7.38 +/- 1.2 micrograms water/micrograms dry wt after superfusion. When a range of superfusate albumin concentrations was used (0, 1, 2, and 3 g/dl), tissue albumin concentration changed 0.59 +/- 0.09 g/dl for each gram per deciliter change in superfusate concentration (P < 0.0001). The large changes in interstitial matrix protein content and hydration suggest that superfusate solution effects need to be considered in microvascular protein transport experiments.

scholarly journals Differential Effects of Refeeding on Melanocortin-Responsive Neurons in the Hypothalamic Paraventricular Nucleus

Endocrinology ◽  
2008 ◽  
Vol 149 (9) ◽  
pp. 4329-4335 ◽  
Author(s):  
Edith Sánchez ◽  
Praful S. Singru ◽  
Runa Acharya ◽  
Monica Bodria ◽  
Csaba Fekete ◽  
...  
Keyword(s):  
Gene Expression ◽  
Paraventricular Nucleus ◽  
Hypothalamic Paraventricular Nucleus ◽  
Mrna Levels ◽  
Sprague Dawley ◽  
Early Action ◽  
Sprague Dawley Rats ◽  
Melanocortin Signaling ◽  
Agouti Related Protein ◽  
Serum Tsh

To explore the effect of refeeding on recovery of TRH gene expression in the hypothalamic paraventricular nucleus (PVN) and its correlation with the feeding-related neuropeptides in the arcuate nucleus (ARC), c-fos immunoreactivity (IR) in the PVN and ARC 2 h after refeeding and hypothalamic TRH, neuropeptide Y (NPY) and agouti-related protein (AGRP) mRNA levels 4, 12, and 24 h after refeeding were studied in Sprague-Dawley rats subjected to prolonged fasting. Despite rapid reactivation of proopiomelanocortin neurons by refeeding as demonstrated by c-fos IR in ARC α-MSH-IR neurons and ventral parvocellular subdivision PVN neurons, c-fos IR was present in only 9.7 ± 1.1% hypophysiotropic TRH neurons. Serum TSH levels remained suppressed 4 and 12 h after the start of refeeding, returning to fed levels after 24 h. Fasting reduced TRH mRNA compared with fed animals, and similar to TSH, remained suppressed at 4 and 12 h after refeeding, returning toward normal at 24 h. AGRP and NPY gene expression in the ARC were markedly elevated in fasting rats, AGRP mRNA returning to baseline levels 12 h after refeeding and NPY mRNA remaining persistently elevated even at 24 h. These data raise the possibility that refeeding-induced activation of melanocortin signaling exerts differential actions on its target neurons in the PVN, an early action directed at neurons that may be involved in satiety, and a later action on hypophysiotropic TRH neurons involved in energy expenditure, potentially mediated by sustained elevations in AGRP and NPY. This response may be an important homeostatic mechanism to allow replenishment of depleted energy stores associated with fasting.

Carvacrol attenuates amikacin-induced nephrotoxicity in the rat

2021 ◽  
Author(s):  
Atta Mohammad Dost ◽  
Mehmet Gunata ◽  
Onural Ozhan ◽  
Azibe Yildiz ◽  
Nigar Vardi ◽  
...  
Keyword(s):  
Inflammatory Cell ◽  
Kidney Tissue ◽  
Control Group ◽  
Histopathological Changes ◽  
Sprague Dawley ◽  
Tissue Samples ◽  
Sprague Dawley Rats ◽  
Before And After ◽  
Per Oral

Abstract Amikacin (AK) is frequently used in the treatment of gram-negative and some gram-positive infections. However, its use is limited due to nephrotoxicity due to the increase in reactive oxygen radicals. The aim of this study was to investigate the role of carvacrol (CAR) against AK-induced nephrotoxicity in rats. Thirty-two Sprague Dawley rats were randomly divided into four groups as control (Vehicle), AK (400 mg/kg), CAR + AK (80 mg/kg CAR + 400 mg/kg AK), and AK + CAR (400 mg/kg AK + 80 mg/kg CAR) groups. AK and CAR were administered via intramuscular and per-oral for 7 days, respectively. Blood and kidney tissue samples were taken at the end of the experiment. Renal function and histopathological changes were compared, and the relevant parameters of oxidative stress and inflammation were detected. Histopathological findings (necrotic changes and dilatation and inflammatory cell infiltration) significantly increased in the AK group compared to the control group. Also, the rats in the AK group lost weight significantly. It was found that CAR treatment before and after AK significantly improved nephrotoxicity histopathologically (p < 0.05). However, this improvement was not detected biochemically. These results show that CAR treatment before and after AK improves nephrotoxicity in the histopathological level.

scholarly journals Paritaprevir and Ritonavir Liver Concentrations in Rats as Assessed by Different Liver Sampling Techniques

2017 ◽  
Vol 61 (5) ◽  
Author(s):  
Charles S. Venuto ◽  
Marianthi Markatou ◽  
Yvonne Woolwine-Cunningham ◽  
Rosemary Furlage ◽  
Andrew J. Ocque ◽  
...  
Keyword(s):  
Surgical Resection ◽  
Needle Aspiration ◽  
Pharmacokinetic Analysis ◽  
Pharmacokinetic Parameters ◽  
Sprague Dawley ◽  
Time Curve ◽  
Tissue Samples ◽  
Drug Concentrations ◽  
Sprague Dawley Rats ◽  
Liquid Chromatography Tandem Mass

ABSTRACT The liver is crucial to pharmacology, yet substantial knowledge gaps exist in the understanding of its basic pharmacologic processes. An improved understanding for humans requires reliable and reproducible liver sampling methods. We compared liver concentrations of paritaprevir and ritonavir in rats by using samples collected by fine-needle aspiration (FNA), core needle biopsy (CNB), and surgical resection. Thirteen Sprague-Dawley rats were evaluated, nine of which received paritaprevir/ritonavir at 30/20 mg/kg of body weight by oral gavage daily for 4 or 5 days. Drug concentrations were measured using liquid chromatography-tandem mass spectrometry on samples collected via FNA (21G needle) with 1, 3, or 5 passes (FNA1, FNA3, and FNA5); via CNB (16G needle); and via surgical resection. Drug concentrations in plasma were also assessed. Analyses included noncompartmental pharmacokinetic analysis and use of Bland-Altman techniques. All liver tissue samples had higher paritaprevir and ritonavir concentrations than those in plasma. Resected samples, considered the benchmark measure, resulted in estimations of the highest values for the pharmacokinetic parameters of exposure (maximum concentration of drug in serum [C max] and area under the concentration-time curve from 0 to 24 h [AUC0–24]) for paritaprevir and ritonavir. Bland-Altman analyses showed that the best agreement occurred between tissue resection and CNB, with 15% bias, followed by FNA3 and FNA5, with 18% bias, and FNA1 and FNA3, with a 22% bias for paritaprevir. Paritaprevir and ritonavir are highly concentrated in rat liver. Further research is needed to validate FNA sampling for humans, with the possible derivation and application of correction factors for drug concentration measurements.

Vasopressin-dependent upregulation of aquaporin-2 gene expression in glucocorticoid-deficient rats

2000 ◽  
Vol 279 (3) ◽  
pp. F502-F508 ◽  
Author(s):  
Takako Saito ◽  
San-E Ishikawa ◽  
Fumiko Ando ◽  
Minori Higashiyama ◽  
Shoichiro Nagasaka ◽  
...  
Keyword(s):  
Gene Expression ◽  
Load Test ◽  
Sprague Dawley ◽  
Water Excretion ◽  
Water Load ◽  
Aquaporin 2 ◽  
Sprague Dawley Rats ◽  
Glucocorticoid Deficiency ◽  
Aqp2 Gene ◽  
Impaired Water

We determined alterations in renal aquaporin-2 (AQP2) gene expression in association with impaired water excretion in glucocorticoid-deficient rats. After adrenalectomy, Sprague-Dawley rats were administered aldosterone alone by osmotic pumps (glucocorticoid-deficient rats). As a control, both aldosterone and dexamethasone were administered. These animals were subjected to the studies on days 7–14. The expressions of AQP2 mRNA and protein in kidney of the glucocorticoid-deficient rats were increased by 1.6- and 1.4-fold compared with the control rats, respectively. An acute oral water load test verified the marked impairment in water excretion in the glucocorticoid-deficient rats. One hour after the water load, the expressions of AQP2 mRNA and protein were significantly reduced in the control rats, but they remained unchanged in the glucocorticoid-deficient rats. However, there was no alteration in [3H]arginine vasopressin (AVP) receptor binding and AVP V2 receptor mRNA expression in the glucocorticoid-deficient rats. A V2-receptor antagonist abolished the increased expressions of AQP2 mRNA and protein in the glucocorticoid-deficient rats. These results indicate that augmented expression of AQP2 participates in impaired water excretion, dependent on AVP, in glucocorticoid deficiency.

Role of renal interstitial hydrostatic pressure in natriuresis of systemic nitric oxide inhibition

1993 ◽  
Vol 264 (3) ◽  
pp. F411-F414 ◽  
Author(s):  
J. A. Haas ◽  
A. A. Khraibi ◽  
M. A. Perrella ◽  
F. G. Knox
Keyword(s):  
Nitric Oxide ◽  
Hydrostatic Pressure ◽  
Fractional Excretion ◽  
Urinary Sodium Excretion ◽  
Renal Perfusion ◽  
Significant Rise ◽  
Sprague Dawley ◽  
Sprague Dawley Rats ◽  
Suprarenal Aorta ◽  
Fractional Excretion Of Sodium

Systemic inhibition of nitric oxide synthesis with NG-monomethyl-L-arginine (L-NMMA) increases renal perfusion pressure (RPP) and urinary sodium excretion. Increased RPP has been proposed as one of the mechanisms for the natriuresis caused by intravenous infusion of L-NMMA. We tested the hypothesis that increases in renal interstitial hydrostatic pressure (RIHP) are required for the natriuresis of L-NMMA infusion. Experiments were performed in four groups of Sprague-Dawley rats in which partial aortic clamping and/or bilateral renal decapsulation was performed to control RPP and RIHP. Infusion of L-NMMA (15 mg/kg bolus + 500 micrograms.kg-1 x min-1 continuous infusion) increased RPP (delta+ 14 +/- 1 mmHg), RIHP (delta+ 3.6 +/- 0.7 mmHg), and fractional excretion of sodium (FENa; delta 2.4 +/- 0.6%, P < 0.005). When RPP was prevented from increasing by controlling RPP with an adjustable clamp around the suprarenal aorta, RIHP and FENa did not significantly change. When only RIHP was held constant by bilateral renal decapsulation, FENa was not significantly increased (delta+ 0.68 +/- 0.36%, not significant), despite a significant rise in RPP (delta+ 18 +/- 2 mmHg, P < 0.001). Control of both RPP and RIHP prevented the increase in FENa. Thus, when renal interstitial pressure was controlled, the infusion of L-NMMA did not result in an increase in FENa. These results demonstrate that an increase in RIHP is a necessary component in the natriuresis due to systemic infusion of L-NMMA.

Effects of TRH on thyrotroph function and number in rat pituitaries transplanted to renal capsule

1986 ◽  
Vol 251 (5) ◽  
pp. E563-E568
Author(s):  
S. Amr ◽  
S. S. Lippman ◽  
B. D. Weintraub
Keyword(s):  
Biologically Active ◽  
Constant Infusion ◽  
Control Group ◽  
Mrna Levels ◽  
Renal Capsule ◽  
Sprague Dawley ◽  
Subunit Mrna ◽  
Sprague Dawley Rats ◽  
Hypophysectomized Rats ◽  
Hypothalamic Influence

We investigated the function of thyrotrophs in rat pituitaries that were transplanted under the renal capsule of 3-wk-old male Sprague-Dawley rats, which were either intact or hypophysectomized. Groups of 12 animals were implanted with osmotic minipumps that delivered a constant infusion of either thyrotropin-releasing hormone (TRH; 1 mg X kg-1 X day-1) or normal saline for 1 wk. In hypophysectomized rats, TRH infusion led to the appearance of substantial amounts of biologically active serum TSH and prevented the hypothyroidism that occurred in the control group. However, TRH did not change the transplant contents of DNA, immunoactive TSH, and mRNA levels for TSH subunits. Comparison of sellar and renal pituitary tissues, obtained from intact rats after 1 wk of either saline or TRH infusion, showed that removal of the pituitary from hypothalamic influence resulted in a 90% depletion of the thyrotroph TSH content. TRH infusion depleted only 63% of the TSH content of sellar thyrotrophs. The mRNA levels for TSH beta-subunit were similar in sellar and transplanted pituitaries and did not significantly change after TRH infusion. When immunocytochemically stained using rat TSH antiserum, the thyrotrophs in pituitary transplants were morphologically and numerically indistinguishable from the thyrotrophs in sellar pituitaries, in the presence or absence of TRH. These data indicate that in transplanted pituitary, for up to 1 wk of a constant infusion, TRH does not significantly affect either the number of thyrotrophs or their ability to synthesize TSH subunit mRNA. However, it is required to maintain released TSH in circulation, since TSH levels were low in the absence of TRH.(ABSTRACT TRUNCATED AT 250 WORDS)

Circadian rhythm of serum and lymph apolipoprotein AIV in ad libitum-fed and fasted rats

1994 ◽  
Vol 267 (5) ◽  
pp. R1385-R1390 ◽  
Author(s):  
K. Fukagawa ◽  
H. M. Gou ◽  
R. Wolf ◽  
P. Tso
Keyword(s):  
Circadian Rhythm ◽  
Important Determinant ◽  
Lymph Flow ◽  
Right Atrial ◽  
Sprague Dawley ◽  
Mesenteric Lymph ◽  
Sprague Dawley Rats ◽  
Ad Libitum ◽  
Ad Libitum Feeding ◽  
Fasted Rats

The aim of the present study was to determine if there is a circadian rhythm in serum and lymph apolipoprotein (apo) AIV and what factors determine this rhythm. Male Sprague-Dawley rats with chronic right atrial catheter were housed in a room illuminated from 0600 to 1800. With ad libitum feeding, serum apo AIV concentration showed a circadian rhythm concomitant with the feeding pattern. In 24-h fasted rats, the serum apo AIV concentration maintained a circadian rhythm and was high during the dark. With mesenteric lymph diversion, serum apo AIV concentration diminished and the circadian rhythm was abolished. The lymph flow, lymph apo AIV, cholesterol, triacylglycerol, and phospholipid contents all exhibited the same circadian rhythm in fasting, with the levels higher in the dark. These circadian rhythms were abolished after bile diversion. In conclusion, serum apo AIV in ad libitum-fed and fasted rats exhibits a circadian rhythm governed by lymph apo AIV output. Furthermore, bile was an important determinant of the circadian rhythm of lymph flow, lymph apo AIV, triacylglycerol, cholesterol, and phospholipid output.

Sign in / Sign up

Export Citation Format

Share Document