Corticosteroids and incorporation of C14-phenylalanine into protein of isolated rat diaphragm

1960 ◽  
Vol 198 (5) ◽  
pp. 1111-1114 ◽  
Author(s):  
Ira G. Wool ◽  
Edward I. Weinshelbaum
Keyword(s):  
Potassium Concentration ◽  
Protein Biosynthesis ◽  
Fold Change ◽  
Prior Treatment ◽  
Rat Diaphragm ◽  
Phenylalanine Concentration ◽  
Intracellular Potassium ◽  
Intracellular Potassium Concentration ◽  
Isolated Rat

Prior treatment of rats with cortisone (2 mg/day) decreased l-phenylalanine-U-C14 incorporation into protein of isolated diaphragm. This action was not affected by a 100-fold change in the phenylalanine concentration, indicating that the steroid depresses protein biosynthesis in muscle. Hydrocortisone (50 µg/ml) added in vitro did not alter C14-phenylalanine incorporation. Large changes in intracellular potassium concentration were without influence on phenylalanine incorporation into protein of diaphragms from normal, adrenalectomized or cortisone-treated rats.

SENSITIVITY OF THE RAT DIAPHRAGM TO GROWTH HORMONE.

1967 ◽  
Vol 54 (4) ◽  
pp. 645-662 ◽  
Author(s):  
Å. Hjalmarson ◽  
K. Ahrén
Keyword(s):  
Growth Hormone ◽  
Inhibitory Effect ◽  
Rat Diaphragm ◽  
Intracellular Accumulation ◽  
Slight Effect ◽  
Kidney Capsule ◽  
Muscle Tissues ◽  
Hypophysectomized Rats ◽  
Isolated Rat

ABSTRACT The effect of growth hormone (GH) in vitro on the rate of intracellular accumulation of the non-utilizable amino acid α-aminoisobutyric acid (AIB) was studied in the intact rat diaphragm preparation. Bovine or ovine GH (25 μg/ml incubation medium) markedly stimulated the accumulation of AIB-14C by diaphragms from hypophysectomized rats, while there was no or only a very slight effect on diaphragms from normal rats. In diaphragms from rats with the pituitary gland autotransplanted to the kidney capsule GH in vitro stimulated the accumulation of AIB-14C significantly more than in diaphragms from normal rats but significantly less than in diaphragms from hypophysectomized rats. Injections of GH intramuscularly for 4 days to hypophysectomized rats made the diaphragms from these rats less sensitive or completely insensitive to GH in vitro. These results indicate strongly that the relative insensitivity to GH in vitro of diaphragms from normal rats is due to the fact that the muscle tissues from these rats has been exposed to the endogenously secreted GH. The results show that GH can influence the accumulation of AIB-14C in the isolated rat diaphragm in two different ways giving an acute or »stimulatory« effect and a late or »inhibitory« effect, and that it seems to be a time-relationship between these two effects of the hormone.

Insulin and incorporation of radioactivity into nucleic acid fraction of isolated diaphragm

1960 ◽  
Vol 199 (4) ◽  
pp. 719-721 ◽  
Author(s):  
Ira G. Wool
Keyword(s):  
Nucleic Acid ◽  
Nucleic Acids ◽  
Glucose Concentration ◽  
Orotic Acid ◽  
Acid Fraction ◽  
Rat Diaphragm ◽  
Isolated Rat

Insulin in vitro stimulated the incorporation into the nucleic acid fraction of isolated rat diaphragm of radioactivity from d-glucose-U-C14, adenine-8-C14 and orotic acid-6-C14; insulin had no effect on the incorporation of thymine-2-C14 into muscle nucleic acids. Insulin enhanced the incorporation into nucleic acids of C14 from adenine and orotic acid in the absence of added glucose, and incorporation of adenine-8-C14 was not influenced by glucose concentration over the range 0–600 mg %.

Direct Effects of Adrenal Cortical Steroids on the Electrolyte Content of Rabbit Leucocytes

1957 ◽  
Vol 190 (1) ◽  
pp. 104-108 ◽  
Author(s):  
D. Laurence Wilson
Keyword(s):  
Potassium Concentration ◽  
Sodium Concentration ◽  
Intracellular Sodium ◽  
Chemical Analyses ◽  
Direct Effects ◽  
Absolute Change ◽  
Sodium And Potassium ◽  
Intracellular Potassium Concentration ◽  
Reciprocal Change

Viable rabbit leucocytes have been obtained in quantities sufficient to permit direct chemical analyses of intracellular sodium and potassium concentrations. Treatment in vitro either with cortisone (10 or 20 mg/l.) or with desoxycorticosterone glycoside (10–80 mg/l.) led to a fall in intracellular potassium concentration and a reciprocal rise in intracellular sodium. There was an associated rise in intracellular water. After cortisone, the absolute change in sodium concentration slightly exceeded the reciprocal change in potassium; after desoxycorticosterone glycoside, the reverse was true.

Muscle Electrolytes and Fluid Compartments in Six Children with Bartter's Syndrome

1978 ◽  
Vol 54 (3) ◽  
pp. 223-231 ◽  
Author(s):  
Christine Delaporte ◽  
J. Stulzaft ◽  
C. Loirat ◽  
M. Broyer
Keyword(s):  
Potassium Concentration ◽  
Negative Relationship ◽  
Plasma Potassium ◽  
Bartter’S Syndrome ◽  
Bartter's Syndrome ◽  
Intracellular Potassium ◽  
Control Subjects ◽  
Fluid Compartments ◽  
Total Muscle ◽  
Intracellular Potassium Concentration

1. Muscle electrolyte (Na, K, Cl, P) concentrations and fluid compartments of six children with Bartter's syndrome were compared with those of 17 control children. From four of the patients biopsies were taken twice, before and after treatment with potassium chloride and spironolactone. Muscle electrolytes were determined by neutron activation in tissue sampled by needle biopsy. Results were expressed in relation to fat-free dry solids. Trapped extracellular fluid was calculated from the chloride space, a normal resting membrane potential being assumed. 2. In hypokalaemic patients total muscle potassium (Km) (33·0 ± 2·1 sem) was below the normal range (43·8 ± 0·7 mmol/100 g of fat-free dry solids) in all cases. When plasma potassium was corrected, total muscle potassium returned to normal. There was a significant correlation between plasma potassium concentration and total muscle potassium (r = 0·87; P < 0·01). Total muscle sodium (Nam) was increased: 18·7 ± 2·9 mmol/100 g in hypokalaemic patients (11·3 ± 0·6 mmol/100 g of fat-free dry solids in control subjects). A negative relationship was found between Km and Nam (r = —0·85; P < 0·01). With treatment, intracellular potassium concentration remained low (142·0 mmol/l of intracellular water; control, 163·0 ± 2·4 mmol/l) despite normokalaemia and normal total muscle potassium. Muscle phosphorus (32·1 ± 1·8 mmol/100 g) was higher than in control subjects (28·1 ± 0·4 mmol/100 g of fat-free dry solids). 3. These data suggest that sodium replaces potassium in muscle of patients with Bartter's syndrome. The low intracellular potassium concentration in the binephrectomized sister of one child and in all treated children suggests that there are generalized anomalies in the handling of cations in Bartter's syndrome.

In vitro Effect of Growth Hormone on the Glucose Uptake of Isolated Rat Diaphragm

Nature ◽  
1957 ◽  
Vol 179 (4557) ◽  
pp. 472-473 ◽  
Author(s):  
P. J. RANDLE ◽  
J. E. WHITNEY
Keyword(s):  
Growth Hormone ◽  
Glucose Uptake ◽  
Rat Diaphragm ◽  
Vitro Effect ◽  
Isolated Rat

THE EFFECT OF GROWTH HORMONE AND OF CORTISOL ON THE RESPONSE OF ISOLATED RAT DIAPHRAGM TO THE STIMULATING EFFECT OF INSULIN ON GLUCOSE UPTAKE AND ON INCORPORATION OF AMINO ACIDS INTO PROTEIN

1959 ◽  
Vol 18 (4) ◽  
pp. 395-408 ◽  
Author(s):  
K. L. MANCHESTER ◽  
P. J. RANDLE ◽  
F. G. YOUNG
Keyword(s):  
Amino Acids ◽  
Growth Hormone ◽  
Protein Synthesis ◽  
Glucose Uptake ◽  
Carbohydrate Metabolism ◽  
Rat Diaphragm ◽  
Pituitary Growth Hormone ◽  
Isolated Rat ◽  
Stimulation Of

SUMMARY 1. The effect of hypophysectomy, or of adrenalectomy, and injection of pituitary growth hormone (GH) or of cortisol, on the uptake of glucose and the incorporation of glycine into protein by isolated rat diaphragm, and the effect of the addition of insulin in vitro on these processes, has been studied. 2. Both hypophysectomy and adrenalectomy raised the uptake of glucose by isolated diaphragm, while treatment of the intact or of the hypophysectomized rat with GH, or of the intact or of the adrenalectomized rat with cortisol, depressed it. Although hypophysectomy and adrenalectomy did not influence the additional glucose uptake induced by 200 mu./ml. of insulin in vitro, both these operations enhanced the effect of 0·1–1·0 mu./ml. of insulin on glucose uptake by diaphragm in vitro. Treatment of the rat with GH or cortisol diminished the rise in glucose uptake of diaphragm induced by 0·1–1·0 mu./ml. insulin. 3. Hypophysectomy depressed, and administration of GH to the intact or hypophysectomized rat raised, the incorporation of glycine into protein of the isolated diaphragm, but neither of these operations altered the magnitude of the stimulation of incorporation induced by 1·0 mu./ml. insulin. 4. Adrenalectomy raised, and administration of cortisol to the intact or adrenalectomized rat depressed, the incorporation of glycine into protein of the isolated diaphragm; adrenalectomy enhanced, the injection of cortisol diminished, the effect of 1·0 mu./ml. insulin on these processes. 5. The possibility that GH directs insulin towards the stimulation of protein synthesis, in part by restraining the action of insulin on carbohydrate metabolism, is discussed.

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