scholarly journals Adaptive enzyme changes in liver and muscle of rats during protein depletion and refeeding

1968 ◽  
Vol 22 (2) ◽  
pp. 153-163 ◽  
Author(s):  
Joan M. L. Stephen
Keyword(s):  
Amino Acid ◽  
Female Rats ◽  
Male Rats ◽  
Casein Diet ◽  
Stock Diet ◽  
Argininosuccinate Lyase ◽  
Depletion Period ◽  
Lyase Activity ◽  
Diet Control ◽  
Enzyme Changes

1. Young rats were kept on a 6% casein diet for 4–7 weeks and then either killed or returned to a stock diet. Control rats were given a stock diet.2. Argininosuccinate lyase (EC 4.3.2.1, L-argininosuccinate arginine-lyase) was assayed in liver, and amino acid activating enzymes were assayed in liver and muscle of rats after depletion and while they were refed on the stock diet. Levels of enzymes were compared with those in the control rats.3. Amino acid activating enzymes were markedly increased in liver at the end of the depletion period, but returned almost to normal levels after 4–6 days of refeeding. In muscle the enzyme levels were not decreased after depletion, but began to rise after 4 days of refeeding.4. Argininosuccinate lyase activity in depleted female rats was about half that in control rats and rose again slowly on refeeding. Male rats were hardly affected by depletion.5. It is suggested that these enzyme changes play a part in the adaptation of the rat to a reduced protein intake.

scholarly journals Methionine sulphoxide as a source of sulphur-containing amino acids for the young rat

1977 ◽  
Vol 37 (1) ◽  
pp. 93-105 ◽  
Author(s):  
Anne U. Gjøen ◽  
L. R. Njaa
Keyword(s):  
Amino Acid ◽  
Blood Plasma ◽  
Fish Meal ◽  
Soya Bean ◽  
Male Rats ◽  
Curvilinear Relationship ◽  
Casein Diet ◽  
Bean Meal ◽  
Soya Bean Meal ◽  
Effect On Growth

1. Young male rats were used in five experiments to study the utilization for growth of methionine sulphoxide, and the relationship between the sulphoxide content in the diet and the level of microbiologically determined methionine activity in blood or blood plasma. In one nitrogen-balance experiment methionine and methionine sulphoxide were compared as supplements to a casein diet and a fish-meal diet.2. Methionine sulphoxide was poorly utilized for growth when tested as the sole sulphur amino acid in an amino acid diet. Substitution of one-third of the sulphoxide with cystine improved utilization so that it approached that of methionine.3. Methionine alone and in combination with methionine sulphoxide were added to a soya-bean-meal diet. The sulphoxide showed no adverse effect on growth.4. Fish meal in which methionine had been oxidized to methionine sulphoxide was tested alone and in combinations with unoxidized fish meal. Only when the oxidized meal was given alone was there an appreciable effect on growth. The fish meals used were low in cystine.5. Whereas both methionine and methionine sulphoxide improved the N balance when a casein diet was given, there was no effect when a fish-meal diet was given.6. There was a linear relationship between methionine sulphoxide content in the amino acid diets and the methionine activity in the blood plasma. Methionine sulphoxide added to a soya-bean-meal diet or present in oxidized fish meal gave a curvilinear relationship, and the observed activities were lower than with the amino acid diets. Methionine activity in blood could not be used as an indicator of moderate amounts of methionine sulphoxide in protein-containing diets.

THE ROLE OF THE ADRENAL GLAND IN THE CONTROL OF AMINO ACID INCORPORATION INTO PROTEIN OF ISOLATED RAT LIVER MICROSOMES

1960 ◽  
Vol 21 (2) ◽  
pp. 177-189 ◽  
Author(s):  
A. KORNER
Keyword(s):  
Amino Acid ◽  
Rat Liver ◽  
Liver Microsomes ◽  
Female Rats ◽  
Male Rats ◽  
Rat Liver Microsomes ◽  
Hypophysectomized Rats ◽  
Normal Rat ◽  
Secondary Result

SUMMARY 1. Microsomes, isolated from rat liver a day after adrenalectomy, incorporate more radioactive amino acid into their protein in vitro than microsomes from normal rat liver. This enhanced rate of incorporation progressively declines with time after adrenalectomy until it reaches a plateau level which is below the normal rate of incorporation. 2. Following adrenalectomy microsomes isolated from liver of male rats show a greater rise in incorporating ability than those from liver of female rats, and maintain it longer. 3. Most of the increased incorporation observed in the in vitro system soon after adrenalectomy of the rat, and most of the decreased incorporation observed in rats adrenalectomized for some time, results from alterations in the microsomes which change their ability to incorporate activated amino acids into proteins. 4. Treatment of rats with cortisol acetate results in an increase in the ability of liver microsomes to incorporate amino acid into protein. This heightened incorporating ability is probably a secondary result of the breakdown of extrahepatic tissue protein which is stimulated by cortisol. 5. Somewhat similar responses to acute adrenalectomy and to treatment with cortisol were found in hypophysectomized rats. 6. The protein anabolic response of adrenalectomized rats to treatment with insulin, and of adrenalectomized-hypophysectomized rats to treatment with insulin or growth hormone, is greater than that shown by rats which possess adrenal glands.

Thirteen-Week Oral Toxicity Study of l-Arginine in Rats

2004 ◽  
Vol 23 (2) ◽  
pp. 101-105 ◽  
Author(s):  
Shoji Tsubuku ◽  
Kazuhisa Hatayama ◽  
Kazunori Mawatari ◽  
Miro Smriga ◽  
Takeshi Kimura
Keyword(s):  
Amino Acid ◽  
Group Treatment ◽  
Clinical Signs ◽  
Female Rats ◽  
Male Rats ◽  
Control Group ◽  
Standard Diet ◽  
Male And Female ◽  
Cell Counts ◽  
Male And Female Rats

The amino acid l-arginine (Arg) has been used extensively in dietary and pharmacological products. This study evaluated toxicological and behavioral effects of Arg produced by Ajinomoto Co. (Tokyo, Japan) during a dosing study with male and female Sprague-Dawley rats. The amino acid was incorporated into a standard diet at doses equal to 1.25%, 2.5%, and 5.0% ( w/w). A control group of rats received only a standard diet. All diets were administered ad libitum for 13 continuous weeks. To examine recoverability of any potential effects, the administration period was followed by a 5-week-long recovery, during which only a standard diet was provided. In male and female rats in each concentration group, treatment-related changes were not observed for clinical signs, body weights, diet consumption, ophthalmology, gross pathology, organ weight, or histopathology. An elevated level of plasma glucose was detected in some male rats (5.0%, w/ w) during the analysis conducted in the fifth week of administration; however, the degree of the change was within the physiological range, and no changes were observed at the end of the administration period. In the same group, an increase in hemoglobin, together with a tendency toward an increase in the red blood cell counts, was found, but the change was considered toxicologically insignificant. The no-observed-adverse-effect level (NOAEL) for Arg was estimated at 5.0% ( w/w) for both genders (males, 3.3 ±0.1 g/kg/day; females, 3.9 ±0.2 g/kg/day).

scholarly journals Gender difference in regulation of branched-chain amino acid catabolism

1997 ◽  
Vol 327 (2) ◽  
pp. 449-453 ◽  
Author(s):  
Rumi KOBAYASHI ◽  
Yoshiharu SHIMOMURA ◽  
Taro MURAKAMI ◽  
Naoya NAKAI ◽  
Noriaki FUJITSUKA ◽  
...  
Keyword(s):  
Amino Acid ◽  
Gender Difference ◽  
Kinase Activity ◽  
Light Period ◽  
Female Rats ◽  
Male Rats ◽  
Amino Acid Catabolism ◽  
Branched Chain Amino Acid ◽  
Activity State ◽  
Branched Chain

Regulation of the activity state of the hepatic branched-chain 2-oxo acid dehydrogenase (BCODH) complex during the light-dark cycle differs markedly in male and female rats. Female rats exhibit a profound diurnal rhythm in the activity state of the complex that is not observed in male rats. Regardless of gender, most of the complex was dephosphorylated and active in the middle of the dark period and early in the light period, and this form of the complex predominated in male rats at the end of the light period. In contrast, most of the complex in female rats became phosphorylated and inactive by the end of the light period. Gonadectomy prevented the diurnal rhythm in females but was without effect in males, indicating that female sex hormones are required for this gender difference in regulation of the BCODH complex. Changes in levels of branched-chain 2-oxo acids, known regulators of BCODH kinase, do not seem to be involved; rather, an increase in BCODH kinase activity occurring between morning and evening is responsible for inactivation of the BCODH complex in female rats. The increase in kinase activity is due to an increase in the amount of kinase protein associated with the BCODH complex. Thus a marked diurnal variation in the amount of BCODH kinase and therefore its activity results in large swings in the activity state of the liver BCODH complex in female rats. This study provides the first evidence for a gender-specific difference in the regulation of branched-chain amino acid catabolism.

scholarly journals Renal functional effects of the highly selective AT2R agonist, β-Pro7 Ang III, in normotensive rats

2020 ◽  
Vol 134 (7) ◽  
pp. 871-884
Author(s):  
Lucinda M. Hilliard Krause ◽  
Brandon A. Kemp ◽  
Amanda Suan Jui Tan ◽  
Emma S. Jones ◽  
Mark P. Del Borgo ◽  
...  
Keyword(s):  
Amino Acid ◽  
Systemic Administration ◽  
Female Rats ◽  
Peptide Sequence ◽  
Male Rats ◽  
Apical Plasma Membrane ◽  
Male And Female ◽  
Excretory Function ◽  
Functional Studies ◽  
Male And Female Rats

Abstract Recently, we designed a group of peptides by sequential substitution of the naturally occurring α-amino acid throughout the Ang III peptide sequence with the corresponding β-amino acid. β-Amino acid substitution at the proline residue of Ang III (β-Pro7-Ang III) resulted in a highly selective AT2R ligand, demonstrating remarkable selectivity for the AT2R in both binding and functional studies. To provide additional functional evidence for the suitability of β-Pro7 Ang III as a novel AT2R agonist, we tested effects of acute systemic administration of β-Pro7-Ang III on renal hemodynamic and excretory function in anesthetized normotensive male and female rats. We also compared the natriuretic effects of acute intrarenal administration of native Ang III and β-Pro7-Ang III in the presence of systemic AT1R blockade in anesthetized female rats to allow for the differentiation of systemic versus direct intrarenal natriuretic actions of β-Pro7-Ang III. In both male and female rats, acute systemic administration of β-Pro7-Ang III elicited renal vasodilatation and natriuresis. Notably, greater renal vasodilatory effects were observed in female versus male rats at the highest dose of β-Pro7-Ang III administered. Moreover, intra-renal administration of β-Pro7-Ang III produced significant natriuretic effects in female rats and, like Ang III, evoked AT2R translocation to the apical plasma membrane in renal proximal tubular cells. Taken together, our findings support the use of β-Pro7-Ang III as a novel AT2R agonist and experimental tool for exploring AT2R function and its potential as a therapeutic target. Furthermore, our findings provide further evidence of a sex-specific influence of AT2R stimulation on renal function.

Changes in renal hemodynamics and excretory function induced by a reduction of ANG II effects during renal development

2007 ◽  
Vol 293 (2) ◽  
pp. R695-R700 ◽  
Author(s):  
Analia Loria ◽  
Virginia Reverte ◽  
Francisco Salazar ◽  
Fara Saez ◽  
M. Teresa Llinas ◽  
...  
Keyword(s):  
Amino Acid ◽  
Renal Hemodynamics ◽  
Female Rats ◽  
Male Rats ◽  
Renal Development ◽  
Ang Ii ◽  
Acid Infusion ◽  
Male And Female ◽  
Amino Acid Infusion ◽  
Age Dependent

The aim was to evaluate whether blockade of ANG II effects during renal development modifies the renal response to an increment of plasma amino acid concentration. It was also examined in anesthetized rats whether the reduction of the renal ability to eliminate an acute volume expansion (VE), elicited by blockade of ANG II during renal development, is sex and/or age dependent. Newborn Sprague-Dawley rats were treated with vehicle or an AT1-receptor antagonist (ARA) during postnatal nephrogenesis. Amino acid infusion induced increments ( P < 0.05) of glomerular filtration rate (31 ± 6%) and renal plasma flow (26 ± 5%) in male but not in female vehicle-treated rats. Natriuretic and diuretic responses to amino acid infusion were similar in male and female vehicle-treated rats. These renal hemodynamics and excretory responses to amino acid infusion were abolished in ARA-treated rats. Renal responses to VE were evaluated at 3–4 and 9–10 mo of age in vehicle and ARA-treated rats. VE-induced natriuresis and diuresis were reduced by more than 38% ( P < 0.05) in 3- to 4-mo-old male and female ARA-treated rats. An age-dependent reduction ( P < 0.05) in the renal ability to eliminate VE was found in male but not in female rats treated with ARA. Our results demonstrate that the renal effects induced by an increment in amino acids are abolished when ANG II effects have been reduced during nephrogenesis. In addition, this reduction of ANG II effects elicits an impairment of the renal ability to eliminate an acute VE in males and females, which is aggravated by age only in male rats.

INDUCTION OF GOITRE BY PTU OR KClO4 IN MALE AND FEMALE RATS. EFFECT OF GONADECTOMY

1973 ◽  
Vol 74 (1) ◽  
pp. 88-104 ◽  
Author(s):  
T. Jolín ◽  
M. J. Tarin ◽  
M. D. Garcia
Keyword(s):  
Iodine Content ◽  
High Plasma ◽  
Disc Electrophoresis ◽  
Female Rats ◽  
Male Rats ◽  
Adult Rats ◽  
Male And Female ◽  
Glucose Levels ◽  
Male And Female Rats ◽  
Tsh Levels

ABSTRACT Male and female rats of varying ages were placad on a low iodine diet (LID) plus KClO4 or 6-propyl-2-thiouracil (PTU) or on the same diet supplemented with I (control rats). Goitrogenesis was also induced with LID plus PTU in gonadectomized animals of both sexes. The weight of the control and goitrogen treated animals, and the weight and iodine content of their thyroids were determined, as well as the plasma PBI, TSH, insulin and glucose levels. The pituitary GH-like protein content was assessed by disc electrophoresis on polyacrylamide gels. If goitrogenesis was induced in young rats of both sexes starting with rats of the same age, body weight (B.W.) and pituitary growth hormone (GH) content, it was found that both the males and females developed goitres of the same size. On the contrary, when goitrogenesis was induced in adult animals, it was found that male rats, that had larger B.W. and pituitary GH content than age-paired females, developed larger goitres. However, both male and female rats were in a hypothyroid condition of comparable degree as judged by the thyroidal iodine content and the plasma PBI and TSH levels. When all the data on the PTU or KClO4-treated male and female rats of varying age and B.W. were considered together, it was observed that the weights of the thyroids increased proportionally to B.W. However, a difference in the slope of the regression of the thyroid weight over B.W. was found between male and female rats, due to the fact that adult male rats develop larger goitres than female animals. In addition, in the male rats treated with PTU, gonadectomy decreased the B.W., pituitary content of GH-like protein and, concomitantly, the size of the goitre decreased; an opposite effect was induced by ovariectomy on the female animals. However, when goitrogenesis was induced in weight-paired adult rats of both sexes, the male animals still developed larger goitres than the females. Among all the parameters studied here, the only ones which appeared to bear a consistent relationship with the size of the goitres in rats of different sexes, treated with a given goitrogen, were the rate of body growth and the amount of a pituitary GH-like protein found before the onset of the goitrogen treatment. Moreover, though the pituitary content of the GH-like protein decreased as a consequence of goitrogen treatment, it was still somewhat higher in male that in female animals. The present results suggest that GH may somehow be involved in the mechanism by which male and female rats on goitrogens develop goitres of different sizes, despite equally high plasma TSH levels.

OXYDATION DES ANABOLIKUMS 1-METHYL-ANDROST-1-EN-17β-OL-3-ON MIT WASSERSTOFFTRANSFER AUF ÖSTRON

1971 ◽  
Vol 67 (3) ◽  
pp. 517-530 ◽  
Author(s):  
Martin Wenzel
Keyword(s):  
Rat Liver ◽  
Anabolic Steroid ◽  
Female Rats ◽  
Male Rats ◽  
Female Rat ◽  
Liver Slices ◽  
Androgen Effects ◽  
Biochemical Difference

ABSTRACT With the aid of metenolon-17α-T a tritium-transfer to oestrone in rat liver slices was demonstrated. This tritium-transfer from metenolon17α-T to oestrone yielding tritium-labelled oestradiol had a higher efficiency in male than in female rat liver. Correspondingly in the presence of metenolon the relation of oestrone to oestradiol is changed more in male than in female rat liver. Looking for biochemical differences between the anabolic steroid metenolon and testosterone the oxydation at C17 was measured in different organs of the rat using 17α-T-labelled steroids. The highest oxydation rate was found for both steroids in the liver. In the sexual organs of male rats the oxydation rate of testosterone was 50–10 times higher than that of the anabolic steroid. This difference was less in sexual organs of female rats. This result of a greater biochemical difference between both steroids in males than in females leads to the question, whether the dissociation between the anabolic and the androgen effects is higher in males than in females.

The effect of dexamethasone on mucosal immunity of uterine tissue during pregnancy in rat

2019 ◽  
Vol 20 (1) ◽  
pp. 75-84
Keyword(s):  
Early Pregnancy ◽  
Histopathological Examination ◽  
Early Period ◽  
Interleukin 10 ◽  
Treated Group ◽  
Female Rats ◽  
Male Rats ◽  
Mrna Levels ◽  
Uterine Tissue ◽  
Leukocytic Infiltration

Disturbances in early pregnancy immunity affect embryo development, endometrial receptivity, placental development, fetal growth and lead to subfertility, dexamethasone is a synthetic glucocorticoid used for treatment of various complications. Immune cells and cytokines were examined during the early pregnancy in twenty-four female rats and six male rats for mating. Rats were grouped into two group control and dexamethasone treated by a dose of 50µgm/kgm body weight daily starting from one week before mating and persisted for one week after pregnancy. Blood samples were collected from each rat at 5hrs and at 1,3,7 day of pregnancy. Extracted RNA was subjected to real time PCR to determine mRNA levels for immune related genes interleukin1a(IL1A) and interleukin 10(IL10). Histopathological examination was done to uterus in order to detect leukocyte infiltration in uterine tissue. Results showed that significant increase in white blood cell count mainly eosinophil at 5hrs and lymphocyte at three and seven day of pregnancy of dexamethasone treated group. Moreover, TNF, C-reactive protein and progesterone were increased mainly at seven day of pregnancy of dexamethasone treated group. Similarly, interleukin 1alpha and interleukin 10 significantly increased at 5hrs and one day of pregnancy of dexamethasone treated group. In contrast, serum levels of total antioxidant capacity and estrogen were decreased significantly at 5hrs and seven day in dexamethasone treated group. Histopathological examination of uterus revealed leukocytic infiltration especially neutrophil and few eosinophils at five hours and one day of gestation then eosinophil become absent at 3day and seven day of dexamethasone group. Epithelial height and uterine gland diameter significantly increased at 5hrs, three day and seven days of gestation of dexamethasone treated group. The present investigation demonstrated that using of dexamethasone by dose of 50µgm/kgm during early pregnancy had a conflicting impact on some immune cytokines and parameters and may reflect a harmful response of immune system toward early period of pregnancy

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