EFFECTS OF ADRENALINE ON CARBOHYDRATE METABOLISM IN THE ISOLATED DIAPHRAGM OF INTACT AND ADRENALECTOMIZED RATS AS INFLUENCED BY »NEMBUTAL« ANAESTHESIA

1960 ◽  
Vol XXXV (IV) ◽  
pp. 541-550 ◽  
Author(s):  
P. R. Bouman ◽  
W. Dermer

ABSTRACT Hemidiaphragms of intact and adrenalectomized rats which had been killed by decapitation, were incubated for 1 hour at 37° C under aerobic conditions. Glucose uptake and glycogen deposition were determined. Addition of adrenaline in vitro (1 μg/ml) caused a substantial decrease in glucose uptake in both types of diaphragms, this decrease being equivalent to a simultaneous inhibition of glycogen deposition. »Nembutal« anaesthesia prior to decapitation was found to alter the response to adrenaline. This change was most clearly observed in diaphragms of adrenalectomized rats. Here, adrenaline mainly affected glycogen metabolism by way of glycogen degradation, whereas the overall magnitude of the response was not materially changed. However, glucose uptake appeared to be only slightly decreased by adrenaline under these conditions. The change in response to adrenaline was attributed to the higher initial glycogen content observed in diaphragms of nembutalized rats. It was suggested that prevention of an acute release of endogenous adrenergic substances, occurring after decapitation of unanaesthetized donor rats, may be the actual cause of this phenomenon. Attention was drawn to the significance of the initial glycogen content as an important factor in carbohydrate metabolism of the isolated rat diaphragm.

1963 ◽  
Vol 44 (1) ◽  
pp. 90-100
Author(s):  
P. R. Bouman ◽  
W. Dermer

ABSTRACT The in vitro effects of adrenaline on glycogen metabolism and glucose uptake were studied in diaphragms of intact, adrenalectomized and adrenodemedullated rats decapitated under »Nembutal« anaesthesia. Adrenalectomy and pretreatment of adrenalectomized rats with cortisol caused an increase in the net loss of glycogen induced by adrenaline. When glycogen deposition in the absence of adrenaline was also taken into account, the overall magnitude of the glycogenolytic response appeared to be unchanged. The apparent qualitative change in response induced by these procedures was attributed to increased initial glycogen values. In diaphragms of adrenalectomized and adrenodemedullated rats the response to adrenaline was identical, the initial glycogen content being the same in these preparations. None of the experimental procedures affected the variable inhibition of glucose uptake by adrenaline. These results do not favour the existence of a »permissive« or synergistic action of adrenocortical steroids with regard to the effects of adrenaline on peripheral carbohydrate metabolism.


1959 ◽  
Vol 18 (4) ◽  
pp. 395-408 ◽  
Author(s):  
K. L. MANCHESTER ◽  
P. J. RANDLE ◽  
F. G. YOUNG

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.


1960 ◽  
Vol XXXV (IV) ◽  
pp. 551-559 ◽  
Author(s):  
P. R. Bouman ◽  
W. Dermer

ABSTRACT Hemidiaphragms of adrenalectomized rats which had been nembutalized prior to decapitation, were incubated under aerobic conditions and the glucose uptake and glycogen deposition were measured. Addition of adrenaline in vitro induced marked glycogen degradation and a relative small decrease in glucose uptake. Pretreatment with adrenaline in vivo, however, appeared to increase glycogen deposition in vitro while glucose uptake increased to an equivalent extent. This effect was attributed to the low initial glycogen content induced by this treatment. Double exposure to adrenaline by administering this substance both in vivo and in vitro, neither affected glucose uptake nor glycogen deposition as compared with untreated control diaphragms. However, there was a significant difference in the glycogen level at which both groups metabolized, this level being extremely low in diaphragms doubly exposed to adrenaline. It was concluded that the action of adrenaline on muscular carbohydrate metabolism consists basically of three different stages: 1. A temporary initial stage during which glucose assimilation is inhibited secondarily to glycogen degradation. 2. A second stage, in which the occurrence of inhibition of glucose assimilation is determined by the fact whether in the corresponding control tissue the glucose uptake is raised in favour of glycogen deposition. 3. A stage of recovery induced by discontinuing the exposure to adrenaline. This stage is characterized by glycogen deposition and an equivalent rise in glucose assimilation.


1960 ◽  
Vol 198 (5) ◽  
pp. 1075-1078 ◽  
Author(s):  
E. R. Berman ◽  
E. Wertheimer

A factor has been found in the serum of fasted rats which inhibits glucose uptake and glycogen synthesis in the isolated rat diaphragm. It does not affect CO2 production or O2 uptake. It is nondialyzable, stable in the cold and also stable when heated to 58°C for 1 hour. It was found in Cohn fraction IV-V. Its action did not resemble any of the known hormones, nor could it be identified as one of the inhibitory factors found in diabetic serum.


Nature ◽  
1957 ◽  
Vol 179 (4557) ◽  
pp. 472-473 ◽  
Author(s):  
P. J. RANDLE ◽  
J. E. WHITNEY

1960 ◽  
Vol XXXV (IV) ◽  
pp. 560-567 ◽  
Author(s):  
P. R. Bouman

ABSTRACT Krebs-Ringer solution in which pancreatic tissue of normal rats had been previously incubated, did not stimulate the glucose uptake of the isolated rat diaphragm. An increased glucose uptake was observed, however, after adding incubate of pancreatic tissue from rats in which the pancreatic ducts had been ligated 6 weeks prior to the experiment. Glucose uptake in the isolated diaphragm was also increased by joint incubation with pancreatic tissue of normal rats. Diaphragmatic glucose uptake was not stimulated by joint incubation with pancreatic tissue of alloxan-diabetic rats. It was concluded that insulin is released from pancreatic tissue under in vitro conditions. Unless muscular tissue is present, this insulin is completely inactivated, presumably by proteolytic pancreatic enzymes.


1956 ◽  
Vol 14 (1) ◽  
pp. 82-86 ◽  
Author(s):  
P. J. RANDLE

SUMMARY An in vitro method of insulin assay based upon the glucose uptake of the isolated rat diaphragm is described and a statistical appraisal of the method given. The minimum concentration of insulin which was detected by this method was of the order of 10−4 i.u. of insulin/ml. The index of precision (λ) varied in eighteen studies of regression from 0·18 to 0·74. The slope of the log dose-response curve was found to vary significantly from experiment to experiment. The results are briefly compared with those obtained with other in vitro methods of insulin assay.


1967 ◽  
Vol 54 (4) ◽  
pp. 645-662 ◽  
Author(s):  
Å. Hjalmarson ◽  
K. Ahrén

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.


1952 ◽  
Vol 197 (1) ◽  
pp. 151-166 ◽  
Author(s):  
C.R. Park ◽  
David H. Brown ◽  
Marvin. Cornblath ◽  
William H. Daughaday ◽  
M.E. Krahl

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