DIE INITIALE VERTEILUNG VON RADIO-C IN DEN ZELLFRAKTIONEN EINIGER RATTENORGANE NACH INJEKTION VON TESTOSTERON-4-14C

1964 ◽  
Vol 47 (1) ◽  
pp. 51-57 ◽  
Author(s):  
K.-O. Mosebach ◽  
W. Dirscherl

ABSTRACT The initial distribution of radioactive C was studied in the cell fractions of the liver, kidney, testes and thigh muscles after intraperitoneal injection of testosterone-4-14C into 40 day old male rats. To make this possible, the absolute and specific activity values (μc/mg C) were determined. After both ten and twenty minutes the cytoplasm fractions possessed the highest activity values, the only exception being the specific activity of the liver cytoplasm ten minutes after injection when the microsomes of the liver showed a higher activity. After 20 min the mitochondria possessed the highest specific activity values among the corpuscular fractions. The specific activity values in the microsomes of all four organs studied were lower 20 min after the time of injection than after 10 min, a fact, which is suspected to be the result of the initial formation of conjugates in the microsomes.

Author(s):  
Aline Byrnes ◽  
Elsa E. Ramos ◽  
Minoru Suzuki ◽  
E.D. Mayfield

Renal hypertrophy was induced in 100 g male rats by the injection of 250 mg folic acid (FA) dissolved in 0.3 M NaHCO3/kg body weight (i.v.). Preliminary studies of the biochemical alterations in ribonucleic acid (RNA) metabolism of the renal tissue have been reported recently (1). They are: RNA content and concentration, orotic acid-c14 incorporation into RNA and acid soluble nucleotide pool, intracellular localization of the newly synthesized RNA, and the specific activity of enzymes of the de novo pyrimidine biosynthesis pathway. The present report describes the light and electron microscopic observations in these animals. For light microscopy, kidney slices were fixed in formalin, embedded, sectioned, and stained with H & E and PAS.


1969 ◽  
Vol 23 (2) ◽  
pp. 271-280 ◽  
Author(s):  
V. R. Young ◽  
P. C. Huang

1. After 14 days on a diet containing 5 or 25% casein male rats received a fracture of the left femur. Four hours before they were killed the injured and control rats were injected with [1-14C]leucine; the incorporation of radioactivity into an isolated fraction of skeletal muscle ribosomes was studied 6, 12, 24, 48, 72, 96 and 228 h after injury.2. The incorporation of [14C]leucine into the ribosome fraction in right thigh muscles dropped to 40% of control values 72 h after fracture in well-nourished rats and after 96 h with diets containing 5 or 25%, casein.3. The specific activity of the trichloroacetic acid-soluble fraction of muscle from injured rats was equal to or higher than that of the controls during the first 72 h but lower at 96 h.4. These results suggest that a reduced incorporation of amino acids by ribosomes from the right thigh muscle occurred on day 3 after fracture in the group receiving 25% casein but not in the group receiving 5% casein.5. Muscle RNA and DNA concentrations were not affected by the injury.6. The relationship between these findings and the loss of muscle N after injury is discussed.


1958 ◽  
Vol 192 (3) ◽  
pp. 592-596 ◽  
Author(s):  
Donald A. Olewine ◽  
Joseph H. Perlmutt

Renal excretions of water, Na+ and K+ were determined over a 5-hour period in sham-operated and adrenalectomized male rats injected intraperitoneally with water (5% body wt.) at postoperative intervals of 3, 14, 21 and 28 days. Intact animals maintained fairly constant outputs. In the adrenalectomized group: decreased excretion of water was apparent by 3 days, but was not maximal until after this interval; Na+ excretion increased after 14 days and rose progressively; and K+ excretion was maximally depressed by 3 days. Diamox (25 mg/100 gm body wt.) increased these values in both groups. The absolute increases in water and K+ excretion for the adrenalectomized animals were less than those for the intact animals, while Na+ excretion exceeded that of the intact group at the 14-day and subsequent intervals. These data indicate that the diuretic does not completely overcome the increased water reabsorption occurring after adrenalectomy and that the Na+—K+ exchange mechanism operates at a reduced capacity. Diamox was ineffective in protecting adrenalectomized rats against water intoxication.


2008 ◽  
Vol 190 (14) ◽  
pp. 4859-4864 ◽  
Author(s):  
Carol Gross ◽  
Roderick Felsheim ◽  
Lawrence P. Wackett

ABSTRACT l-(−)-Azetidine-2-carboxylate (AC) is a toxic, natural product analog of l-proline. This study revealed the genes and biochemical strategy employed by Pseudomonas sp. strain A2C to detoxify and assimilate AC as its sole nitrogen source. The gene region from Pseudomonas sp. strain A2C required for detoxification was cloned into Escherichia coli and sequenced. The 7.0-kb region contained eight identifiable genes. Four encoded putative transporters or permeases for γ-amino acids or drugs. Another gene encoded a homolog of 2-haloacid dehalogenase (HAD). The encoded protein, denoted l-azetidine-2-carboxylate hydrolase (AC hydrolase), was highly overexpressed by subcloning. The AC hydrolase was shown to catalyze azetidine ring opening with the production of 2-hydroxy-4-aminobutyrate. AC hydrolase was further demonstrated to be a new hydrolytic member of the HAD superfamily by showing loss of activity upon changing aspartate-12, the conserved active site nucleophile in this family, to an alanine residue. The presence of a gene encoding a potential export chaperone protein, CsaA, adjacent to the AC hydrolase gene suggested that AC hydrolase might be found inside the periplasm in the native Pseudomonas strain. Periplasmic and cytoplasmic cell fractions from Pseudomonas sp. strain A2C were prepared. A higher specific activity for AC hydrolysis was found in the periplasmic fraction. Protein mass spectrometry further identified AC hydrolase and known periplasmic marker proteins in the periplasmic fraction. A model was proposed in which AC is hydrolyzed in the periplasm and the product of that reaction is transported into and further metabolized in the cytoplasm.


Development ◽  
1972 ◽  
Vol 28 (1) ◽  
pp. 1-11
Author(s):  
Marcus Singer ◽  
J. Douglas Caston

The well-documented nerve dependence of limb regeneration in the newt was analysed by study of accumulation of newly synthesized macromolecules following denervation. The specific activity of RNA and DNA in the denervated early regenerate bud was determined following intraperitoneal injection of [3H]-uridine and [3H]-thymidine. Results showed an outburst in the incorporation into RNA and DNA which reached a peak 3 h after denervation for the former and 7 h for the latter. There was then a decline in incorporation to a plateau about 50–60% of the control non-denervated side within 48 h. Combining these results with our previous demonstration of a similar outburst in the accumulation of newly synthesized protein with a peak at 4 h, the sequence of the outbursts was in order RNA, protein and DNA. The results are interpreted to mean that the nerve influences either macromolecular synthesis or macromolecular processing and turnover, and therefore accumulation in the regenerate.


2020 ◽  
Author(s):  
Dilidaer Xilifu ◽  
Alimu Kateer ◽  
Nijiati Rehemu ◽  
Zhao-yong Li ◽  
jie Jiang ◽  
...  

Abstract Background: Hyperuricemia is the most important risk factor for gout, hypertension, coronary artery disease and other cardiovascular diseases. The incidence of hyperuricemia gradually increased in recent years and it is very necessary to explore the medications of the prevention and treatment of hyperuricemia using hyperuricemia animal models. Objective: The objective of present study is to explore the optimal dose of yeast extract and oteracil potassium in the establishment of hyperuricemia rat model. Method: Sixty-four male rats were randomly divided into 8 experimental groups. Rats were treated with yeast extract by intraperitoneal injection or yeast extract by intraperitoneal injection combined with various doses of oteracil potassium by intragastric feeding or intraperitoneal injection for 28 days. The serum uric acid, urea nitrogen and creatinine levels of different groups were measured at 0th day, 7th day, 14th day, 21th day and 28th day. Results: The serum levels of uric acid in the groups of intraperitoneal injection with yeast extract alone, yeast extract by intraperitoneal injection combined with 50-200 mg/kg oteracil potassium by intragastric feeding and yeast extract by intraperitoneal injection combined with 50-100 mg/kg oteracil potassium by intraperitoneal injection were higher than that in the control group. But we found no significant effect on rat kidney, heart or artery in the above groups. In the group of yeast extract by intraperitoneal injection combined with 200 mg/kg oteracil potassium by intraperitoneal injection, we observed the significantly high level of serum uric acid and morphological and pathological changes in rat kidney, heart and artery. Conclusion: In the present study, we found that continuously treated with yeast extract combined with oteracil potassium is an effective method to establish rat hyperuricemia model. Intraperitoneal injection of yeast extract combined with 200 mg/kg oteracil potassium is an optimal dosage for the construction of a persistent and stable hyperuricemia animal model.


1955 ◽  
Vol 33 (1) ◽  
pp. 54-61 ◽  
Author(s):  
J. E. Logan ◽  
F. C. Heagy ◽  
R. J. Rossiter

The specific activity of the liver RNA nucleotide phosphorus, relative to the specific activity of the liver inorganic phosphate, was determined in the rat, 16 hr. after an intraperitoneal injection of radioactive inorganic phosphate. The nucleotides were isolated by ionophoresis on paper strips.Hypophysectomy caused a decrease in the relative specific activity of each of the four RNA nucleotides. The administration of ACTH caused an increase in the incorporation of P32 into each of the RNA nucleotides of the liver of hypophysectomized animals, but it caused a small and statistically significant decrease in normal animals. Adrenalectomy, either in normal or in hypophysectomized rats, did not affect the P32 incorporation, nor did the administration of ACTH in the absence of the adrenal glands.It is concluded that ACTH can affect the incorporation of P32 into the RNA of the liver and that this effect is due to the action of the hormone on the adrenal cortex. However, other factors also must be operative, since removal of the adrenal glands does not cause the decrease in the P32 incorporation observed after removal of the pituitary.


1988 ◽  
Vol 255 (5) ◽  
pp. G696-G699
Author(s):  
R. W. Egnor ◽  
S. G. Vaccarezza ◽  
A. N. Charney

We examined several sources of error in isotopic flux measurements in a commonly used experimental model: the study of 22Na and 36Cl fluxes across rat ileal tissue mounted in the Ussing flux chamber. The experiment revealed three important sources of error: the absolute counts per minute, the difference in counts per minute between serial samples, and averaging of serial samples. By computer manipulation, we then applied hypothetical changes in the experimental protocol to generalize these findings and assess the effect and interaction of the absolute counts per minute, the sampling interval, and the counting time on the magnitude of the error. We found that the error of a flux measurement will vary inversely with the counting time and the difference between the consecutive sample counts per minute used in the flux calculations and will vary directly with the absolute counts per minute of each sample. Alteration of the "hot" side specific activity, the surface area of the tissue across which flux is measured and the sample volume have a smaller impact on measurement error. Experimental protocols should be designed with these methodological considerations in mind to minimize the error inherent in measuring isotope flux.


1977 ◽  
Vol 232 (5) ◽  
pp. E522
Author(s):  
M Lis ◽  
R Boucher ◽  
M Chrétien ◽  
J Genest

Tonin, an enzyme present in rat submaxillary gland, converts angiotensin I to angiotensin II and is able to form angiotensin II directly from renin substrates. This enzyme was previously shown to be different from renin, tissue isorenins, and angiotensin I converting enzyme. The specific activity of tonin in rat submaxillary gland increases with the age of the animal and is much higher in male than in female rats; this sex difference is apparent from 60 to 70 days of age. There is a sharp drop of tonin activity in hypophysectomized animals, whereas adrenalectomy, thyroidectomy, and gonadectomy have have little effect. The marked increase in tonin activity was observed in animals bearing MtT-F4 transplantable tumors known to produce ACTH, prolactin, and growth hormone. Tonin specific activity in hypophysectomized male rats is restored to control levels by combined treatment with growth hormone and testosterone. Prolactin alone or in combination with testosterone, as well as transplanted pituitaries, has no effect in hypophysectomized animals. There is a significant specific binding of 125I-labeled growth hormone to isolated membranes of rat submaxillary gland.


1985 ◽  
Vol 248 (6) ◽  
pp. G639-G642 ◽  
Author(s):  
R. B. Kirkpatrick ◽  
N. M. Wildermann ◽  
P. G. Killenberg

The effect of estrogens and androgens on hepatic glycolithocholate sulfotransferase activity was studied in male rats. Significant increases in specific activity were noted following treatment of rats for 21 days with 17 beta-estradiol, 17 alpha-ethynylestradiol, and the nonsteroidal estrogen agonists nafoxidine, tamoxifen, and diethylstilbestrol. Similar treatment of male rats with 5 alpha-dihydrotestosterone, hydrocortisone, norethindrone, and prolactin did not affect activity. To further assess the effect of androgens, male rats were castrated. Glycolithocholate sulfotransferase activity increased fivefold by 14 days after castration. Treatment of castrated rats with 5 alpha-dihydrotestosterone prevented the increase and maintained activity at the level of sham-operated animals. Castrated animals exhibited an additional increment in activity following treatment with 17 alpha-ethynylestradiol: specific activity in these animals rose to levels comparable with those measured in untreated female rats. These data suggest endogenous androgens maximally suppress hepatic glycolithocholate sulfotransferase activity in male rats. The data also indicate that activity is stimulated by estrogenic compounds of varied chemical structure and that stimulation is not solely due to suppression of androgen release by the testes as a consequence of estrogen treatment.


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