scholarly journals Polyamine and intestinal properties in adult rats

1996 ◽  
Vol 76 (4) ◽  
pp. 627-637 ◽  
Author(s):  
Patricia Deloyer ◽  
Guy Dandrifosse ◽  
Catherine Bartholomeus ◽  
Nadine Romain ◽  
Monique Klimek ◽  
...  
Keyword(s):  
Body Weight ◽  
Specific Activity ◽  
Experimental Conditions ◽  
Adult Rats ◽  
Distal Intestine ◽  
Germ Free ◽  
Polyamine Content ◽  
Intestinal Functions ◽  
Wet Weight ◽  
Specific Activities

We questioned whether polyamines coming from the diet or produced by intestinal microflora or by intracellular metabolism influence intestinal functions. Therefore, we compared pathogen-free rats and germ-free rats receiving a diet with low polyamine content and either treated or not treated with difluoromethylornithine (DFMO) and/or methylglyoxal bis (guanylhydrazone) (MGBG). Wet weight, protein content, DNA content, sucrase (EC3.2.1.48), maltase (EC 3.2.1.20) and lactase (EC 3.2.1.23) specific activities, amounts of putrescine, spennidine and spemine were measured in the mucosa of the proximal and distal intestine. Body weight was also determined. Rats without microflora had a higher specific activity of maltase and higher amounts of spermidine and spermine but lower lactase specific activity than pathogen-free animals; the low-polyamine diet given to gem-free rats had little effect on the functional variables measured (decrease of maltase and lactase specific activities) and did not modify the amounts of polyamines. DFMO and/or MGBG administered to germ-free rats receiving a low-polyamine diet induced modifications of most of the variables studied. Body weight and wet weight of proximal and distal intestine decreased, disaccharidase specific activities decreased, and amounts of polyamines changed according to the inhibitor used. Thus, our results showed that the deprivation of polyamine supply from microflora or from the diet failed, under our experimental conditions, to affect the intestinal properties analysed but exogenous and endogenous polyamine restriction altered general properties of the organism as well as intestinal functions.

FACTORS INFLUENCING THE EXCRETION OF A FAT-MOBILIZING SUBSTANCE IN THE URINE OF RATS

1966 ◽  
Vol 44 (1) ◽  
pp. 95-101 ◽  
Author(s):  
J. R. Beaton ◽  
A. J. Szlavko ◽  
J. A. F. Stevenson
Keyword(s):  
Body Weight ◽  
Sex Difference ◽  
Specific Activity ◽  
Young Male ◽  
Total Activity ◽  
Female Rats ◽  
Male Rats ◽  
Diabetic Rat ◽  
Adult Rats ◽  
Factors Influencing

The effect of various factors on excretion of a lipid-mobilizing activity in FMS IA (anorexigenic) and in FMS IB (fat-mobilizing) by the fasting rat has been investigated. During fasting, the greatest excretion of such activity in FMS IA and FMS IB occurred in the first 24 hours and diminished thereafter up to 72 hours; and the specific activity of FMS IB was greatest in the first 24 hours whereas that of FMS IA was constant throughout. The hypothalamicobese rat excretes FMS IA and FMS IB in greater than normal amounts. The alloxan-diabetic rat excretes less total activity of FMS IA and IB than do control animals. Young male rats excrete greater amounts of FMS IB, but not of FMS IA, than do adult rats, the greatest excretion per 100 g body weight being observed at approximately 37 days of age. At 27 days of age (prepuberty), male rats excreted a greater total activity of FMS IB but not of FMS IA than did female rats. At 90 days of age (post-puberty), there was no apparent sex difference in the amount of total activity of FMS IB excreted per rat, but when expressed per 100 g body weight, females excreted more FMS IB than did males.

Regrowth of atrophied skeletal muscle in adult rats after ending immobilization

1978 ◽  
Vol 44 (2) ◽  
pp. 225-230 ◽  
Author(s):  
F. W. Booth
Keyword(s):  
Skeletal Muscle ◽  
Body Weight ◽  
Adult Female ◽  
Total Protein ◽  
Recovery Time ◽  
Time Course ◽  
Citrate Synthase ◽  
Female Rats ◽  
Adult Rats ◽  
Wet Weight

The recovery time course of muscle atrophied by immobilization was followed after removal of hindlimb casts from adult female rats. Increases of only 9% in body weight, 4% in gastrocnemius weight, and 10% in soleus weight occurred in controls during the 78-day duration of the experiment. There were no increases in the amounts of total protein or of citrate synthase activities in gastrocnemius or soleus during the first 3 days after removal of hindlimb casts; thereafter, there were increases in these paramters. Citrate synthase activities per mg of gastrocnemius protein were significantly higher at the 16th and 50th day of recovery. No significant differences for citrate synthase activity per mg of soleus occurred during recovery. Until the 50th day of recovery, no significant differences for total protein in soleus and for total protein and wet weight of gastrocnemius were observed between control and recovery values. However, the wet weight of the soleus returned rapidly during recovery and was not significantly different from control during recovery.

Inhibition of Leydig cell activity in vivo and in vitro in hypothyroid rats

1995 ◽  
Vol 144 (2) ◽  
pp. 293-300 ◽  
Author(s):  
F F Antony ◽  
M M Aruldhas ◽  
R C R Udhayakumar ◽  
R R M Maran ◽  
P Govindarajulu
Keyword(s):  
Body Weight ◽  
Leydig Cell ◽  
Specific Activity ◽  
Cell Activity ◽  
Adult Rats ◽  
Hydroxysteroid Dehydrogenases ◽  
Serum Lh ◽  
Prepubertal Age

Abstract Leydig cell steroidogenic activity under basal and stimulated conditions was studied in hypothyroid rats. Hypothyroidism was induced at a prepubertal age (30 days postpartum) by surgical thyroidectomy, and l-thyroxine (T4) supplementation (6 μg/100 g body weight/day for 30 days) to hypothyroid rats was begun after 30 days. Hypothyroidism for 60 days reduced serum LH and FSH without affecting prolactin. Serum and intratesticular testosterone and the specific activity of Leydig cell 3β- and 17β-hydroxysteroid dehydrogenases diminished in hypothyroid rats. The stimulatory effect of LH on Leydig cell steroidogenic activity and cAMP was also adversely affected in hypothyroid rats. All these changes were reversed by T4 supplementation. The present results suggest that prepubertal hypothyroidism suppresses both basal and stimulated Leydig cell activity in adult rats. Journal of Endocrinology (1995) 144, 293–300

Extravascular Albumin Mass and Exchange in Rat Tissues

1970 ◽  
Vol 39 (6) ◽  
pp. 705-724 ◽  
Author(s):  
J. Katz ◽  
G. Bonorris ◽  
Sybil Golden ◽  
A. L. Sellers
Keyword(s):  
Body Weight ◽  
Ascitic Fluid ◽  
Specific Activity ◽  
The Body ◽  
Rat Tissues ◽  
Extracellular Water ◽  
Tissue Extracts ◽  
Albumin Content ◽  
Multicompartmental Analysis ◽  
Specific Activities

1. Extravascular albumin in carcass, skin and gut of rats was extracted and the albumin content estimated by several methods. Assay by electrophoresis on acrylamide gel, by immunodiffusion and by radioimmunoassay were in essential agreement. The method used previously, precipitation with antibody followed by alcohol-TCA extraction, underestimates the amount of albumin in tissue extracts, because extraction from the antibody precipitate is not complete. This method is valid, however, for specific activity determination. 2. Normal rats contain from 500 to 650 mg of albumin per 100 g body weight. Of this, 20–25% is in the circulation, 35–40% in the carcass (mainly but not exclusively muscle), 20–25% in skin and 10% in gut. 3. The extracellular water of muscle, carcass, skin and gut was estimated from the distribution of mannitol and sulphate. With the exception of gut, both methods agreed closely. Extracellular, extravascular water constitutes about 23% of the body weight of 150–200 g rats. The extracellular water in muscle is about 20% and in skin, 40%. In gut the extracellular water cannot be estimated reliably by these compounds. 4. Muscle contains about 3·5 mg/g of extravascular albumin; skin and gut, 7–8 mg/g. The concentration of extravascular albumin in extracellular water of muscle and skin is 1620 mg/ml, or 5060% of the concentration in plasma. In the small intestine the concentration of albumin is higher, possibly similar to that in plasma. 5. In rats with severe aminonucleoside nephrosis, body albumin was depleted to 100–200 mg/100 g. Of this, 15–25% was in plasma, 50% in carcass, and about 15% in skin. Ascitic fluid contained only a few mg of albumin. 6. The specific activity of extravascular albumin of tissues was followed after intravascular injection of 125I- or 131I-labelled albumin. The specific activity of carcass albumin increases rapidly, becoming equal to that in plasma after less than 2 days. The specific activity of albumin in skin increases much more slowly and becomes equal to that of plasma after 4 days. Labelling of albumin of gut is even slower. The specific activities in tissue never exceed that in plasma. 7. In severely nephrotic rats, specific activities in carcass and skin become equal to that in plasma within 2–3 days and remain equal thereafter. Specific activity of albumin in ascitic fluid increases to reach values as much as sixteen-fold those in plasma. 8. The extravascular pool, as calculated by multicompartmental analysis from the slopes and intercepts of the plasma curve, is about equal to that in plasma and in severely nephrotic rats is less than that in plasma. Discrepancies between calculated and observed extravascular albumin masses is by a factor of 3 in normal rats and 10 or more in severely nephrotic rats. 9. Specific activity of extravascular albumin as calculated from multicompartmental analysis is 1·5 times that in plasma in normal rats and at least six times that in plasma in severely nephrotic rats. Actually, the specific activities in extravascular and vascular albumin ultimately become and remain equal. 10. It is concluded that the multicompartmental model of vascular pool exchange with one or two extravascular pools is not valid for rats and probably not for other animal species.

Effect of propylthiouracil-induced hypothyroidism on phosphatidylcholine, phosphatidylethanolamine, and sphingomyelin synthesis in chick liver microsomes

1976 ◽  
Vol 54 (1) ◽  
pp. 15-21 ◽  
Author(s):  
E. M. Lyman ◽  
J. L. Dove ◽  
M. Sribney
Keyword(s):  
Endoplasmic Reticulum ◽  
Body Weight ◽  
Specific Activity ◽  
Liver Microsomes ◽  
Specific Activities ◽  
Low Levels

Biosynthesis of phosphatidylcholine, phosphatidylethanolamine, and sphingomyelin was studied in liver endoplasmic reticulum obtained from newly hatched chicks which were made hypothyroid by feeding 0.2% propylthiouracil.In vitro measurements were made of the specific activities of phosphorylcholine-glyceride (cholinephosphotransferase (EC 2.7.8.2)), phosphorylethanolamine-glyceride (ethanolamine-phosphotransferase (EC 2.7.8.1)), and phosphorylcholine-ceramide (ceramide cholinephosphotransferase (EC 2.7.8.3)) transferases in control and hypothyroid chick liver for a period of 40 days. The specific activity of all three transferases began to decline after the chicks were on the propylthiouracil-containing diet for 5 days and steadily declined, reaching levels 10–15% of the controls after 15 days. These low levels were maintained for as long as the chicks were on this diet.Administration of L-thyroxine (15 μg/100 g of body weight) to the hypothyroid chicks caused a marked increase in the specific activities of all three transferases, reaching levels similar to those seen in the control chicks in 36–48 h. The specific activities then declined as the chicks were maintained on the diet of propylthiouracil, reaching the former low levels after 120 h.Administration of cycloheximide alone to the hypothyroid chicks caused a rise in the specific activities of the transferases after 24 h approximately equal to that caused by thyroxine alone, while thyroxine and cycloheximide together were no different than either alone.These studies indicate that in some manner circulating thyroxine controls the activities of enzymes involved in the biosynthesis of phosphatidylcholine, phosphatidylethanolamine, and sphingomyelin in chick liver endoplasmic reticulum. There was no evidence that induction of hypothyroidism by propylthiouracil had any effect on the activities of these enzymes in the CNS.

scholarly journals Effect of glucose deprivation on rat glutamine synthetase in cultured astrocytes

1996 ◽  
Vol 315 (2) ◽  
pp. 607-612 ◽  
Author(s):  
Françoise ROSIER ◽  
Dominique LAMBERT ◽  
Jeannine MERTENS-STRIJTHAGEN
Keyword(s):  
Glutamine Synthetase ◽  
Specific Activity ◽  
Glucose Deprivation ◽  
Synthesis Rate ◽  
Synthetase Activity ◽  
Glutamine Synthetase Activity ◽  
Sprague Dawley ◽  
Experimental Conditions ◽  
Adult Rats ◽  
Total Recovery

Glutamine synthetase was purified from the cerebral cortex of adult rats and characterized. Polyclonal rabbit antibodies were raised against the enzyme, purified and their specific anti-(glutamine synthetase) activity determined. A primary astroglial culture was prepared from newborn Sprague–Dawley rats. Astrocytes at different ages of development were incubated in the presence and absence of glucose. In glucose-deprived conditions the specific activity of glutamine synthetase decreased. This decrease was more pronounced in 8-day-old than in 21-day-old cultures. Kinetic analysis demonstrated that the reduction in activity was mainly related to a decrease in Vmax. By immunoprecipitation, it was shown that the number of enzyme molecules in astrocytes was decreased in glucose-deprived conditions. On addition of glucose, a total recovery of glutamine synthetase was obtained after 36 h in 8-day-old culture. Rates of degradation and synthesis were investigated. When compared with an incubation in the presence of glucose, glucose deprivation increased enzyme turnover, as estimated from the first-order disappearance of radioactivity from glutamine synthetase. Synthesis rate was estimated from the incorporation of [35S]methionine during a 2 h incubation period and was decreased in glucose-deprived conditions. Trichloroacetate-precipitable proteins changed only slightly in the experimental conditions, and total protein did not vary significantly during the experimental period. A mathematical model is presented which attempts to integrate degradation and synthesis in our experimental model.

Equilibration between tissue calcium and injected radiocalcium in the rat

1964 ◽  
Vol 207 (4) ◽  
pp. 947-952 ◽  
Author(s):  
B. J. Mulryan ◽  
M. W. Neuman ◽  
W. F. Neuman ◽  
T. Y. Toribara
Keyword(s):  
Soft Tissues ◽  
Specific Activity ◽  
The Other ◽  
Adult Rats ◽  
General Significance ◽  
Rapid Exchange ◽  
Other Hand ◽  
Parathyroid Extract ◽  
Tissue Calcium ◽  
Specific Activities

The exchange of calcium in soft tissues was studied in normal and slightly hyperparathyroid, adult rats. Both chemical and radiocalcium assays were performed on a variety of tissues at periods from 10 min to 1 hr and also 1 to 4 days after Ca45 injections. Bone, brain, tendon, and muscle were found to exchange quite slowly, requiring from several hours to several days to equilibrate with the circulation. On the other hand, skin, lung, heart, liver, uterus, and kidney showed specific activities equal to or greater than that of the circulating blood within 10 min. Thereafter, the specific activities of these tissues fell rapidly, approximating the rapidly decreasing specific activity of serum. No significant alterations in these patterns were caused by parathyroid extract. The general significance of this rapid exchange of calcium in many soft tissues is discussed.

Biochemical changes in rat endometrium induced by oestrogens

1981 ◽  
Vol 96 (3) ◽  
pp. 382-388 ◽  
Author(s):  
Marta Jelínková ◽  
J. Jelínek ◽  
J. van der Vies
Keyword(s):  
Marked Effect ◽  
Specific Activity ◽  
Krebs Cycle ◽  
Regression Curve ◽  
Adult Rats ◽  
Oestrogen Treatment ◽  
Linear Dose ◽  
Cycle Plays ◽  
Wet Weight ◽  
Ovariectomized Adult Rats

Abstract. The effect of oestradiol (Oe2) or ethinyloestradiol (EOe) on several enzymes, soluble protein and DNA in the endometrium was studied in ovariectomized adult rats. The most marked effect of Oe2 was the increase in the activity of lactate dehydrogenase (LDH). If the treatment was started on the day of ovariectomy, it took approximately 8 days to reach a constant elevation. If the administration of Oe2 was started one week after castration, the maximum response was seen after 4 days of treatment. Using the latter schedule a linear dose-reponse regression curve of LDH/DNA was obtained with λ = 0.086. This parameter is considered suitable for the comparison of the effects of different oestrogens. Administration of Oe2 for 8 days beginning on the day of ovariectomy gave no linear dose-response curve of LDH/DNA. Administration of EOe caused a very marked increase of the specific activity of pyruvate kinase, LDH, M-type LDH and some slight, but significant decreases in isocitrate dehydrogenase, glutamate dehydrogenase, acid phosphatase and alkaline phosphatase. The changes of β-glucuronidase were only slight. The content of DNA per wet weight of endometrium decreased after oestrogen treatment, the protein content remained reasonably constant. It is concluded that, after stimulation with oestrogen, the rat endometrium produces the energy needed for its own growth mainly via anaerobic glycolysis and that the Krebs cycle plays a relatively small role.

Physiological conditions for the study of basal and meal stimulated exocrine pancreatic secretion in the dog. Absence of feedback inhibition of basal secretion

1982 ◽  
Vol 60 (10) ◽  
pp. 1287-1295 ◽  
Author(s):  
G. Roblès Diaz ◽  
M. A. Devaux ◽  
C. D. Johnson ◽  
Z. Adrich ◽  
H. Sarles
Keyword(s):  
Body Weight ◽  
Pancreatic Juice ◽  
Pancreatic Secretion ◽  
Specific Activity ◽  
Feedback Inhibition ◽  
Secretory Activity ◽  
Experimental Conditions ◽  
Physiological Conditions ◽  
Transient Rise ◽  
Secretion Rates

Pancreatic secretion has been studied in dogs in basal and postprandial conditions, as nearly physiological as possible. When pancreatic juice was excluded from the duodenum pancreatic secretion was not raised. compared with secretion during the return of juice to the duodenum. In fact, in seven mongrels, returning pancreatic juice led a transient rise in pancreatic secretion. This was not seen in five beagles. These results indicate that dogs do not manifest the feedback control of pancreatic secretion by pancreatic juice observed in other species. Pancreatic secretory activity was determined in 10 dogs after stimulation by food. The highest secretion rates occurred during the initial 60 min. The maximal secretion of protein occurred before the maximal secretion of fluid and bicarbonate. The effect of the meal diminished slowly during the subsequent minutes but did not reach basal levels after 2 h. In physiological conditions, maximal pancreatic secretion of fluid and bicarbonate was about one-fifth and of protein was almost one-seventh of the maximal secretory capacity obtained with secretin and cholecystokinin, respectively. Potential specific activity of trypsinogen was unchanged during the different experimental conditions. Trypsinogen output represented a constant average of 20% of protein output. The interindividual variability of pancreatic secretion rates was reduced when outputs were expressed per kilogram of body weight. In general, a significant positive correlation was found between body weight and the secretory outputs. No differences were observed in the response of mongrel and beagle dogs to a meal.

Rapidity of compensatory lung growth following pneumonectomy in adult rats

1979 ◽  
Vol 46 (2) ◽  
pp. 326-333 ◽  
Author(s):  
D. E. Rannels ◽  
D. M. White ◽  
C. A. Watkins
Keyword(s):  
Body Weight ◽  
Cell Size ◽  
Left Lung ◽  
Weight Ratio ◽  
Lung Growth ◽  
Body Weight Ratio ◽  
Adult Rats ◽  
Lung Weight ◽  
Wet Weight ◽  
The Right

The rapidity with which lung growth was initiated following pneumonectomy was investigated using rats (330 g) in which lung weight-to-body weight ratio and lung cell size had stabilized. Following removal of the left lung, right lung weight increased from 823 to 1.161 mg within 7 days. Right lung weight in sham-operated animals did not change significantly. At day 7, right lung weight-to-body weight ratio in pneumonectomized rats was equal to that of both lungs in sham-operated animals; these values remained equal through day 14. Growth of individual lobes of the right lung was generally in proportion to their initial weights. Dry-to-wet weight ratio in either lung of sham-operated or pneumonectomized animals was unchanged, as compared to unoperated controls. Total right lung RNA and protein increased significantly by day 2 and reached levels equal to those in both lungs of sham-operated animals by day 7. Synthesis of lung proteins, estimated during 120 min of perfusion in situ, was elevated 25% on day 3. Incorporation of [3H]thymidine into DNA increased somewhat on day 2 and was elevated fourfold on day 3, corresponding with the initial accumulation of total DNA within the lung. These observations suggested that increased cell size may accompany early compensatory growth following pneumonectomy, but that the major portion of the response involved cellular hyperplasia.

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