Effect of Thioctic Acid on Glucose Oxidation by Liver Slices

Nature ◽  
1955 ◽  
Vol 176 (4486) ◽  
pp. 788-789 ◽  
Author(s):  
J. BORNSTEIN ◽  
BERYL D. HARTMAN
1967 ◽  
Vol 45 (6) ◽  
pp. 979-989 ◽  
Author(s):  
H. J. Duncan ◽  
R. H. Common

The value of the quotient, 14CO2 liberated from glucose-1-14C over 14CO2 liberated from glucose-6-14C, for chicken liver slices has been determined. It did not deviate appreciably from unity for slices from (a) immature and sexually mature females, (b) a group of females at intervals during their transition from sexual immaturity to sexual maturity, (c) immature males, and (d) immature females treated by injection with estradiol monobenzoate. Incubation of the liver slices under anaerobic conditions reduced CO2 liberation to very low values and approximately doubled the quotient. Incubation in the presence of arsenite reduced oxidation but increased the quotient about fourfold. Incubation under anaerobic and aerobic conditions, with addition of pyruvate, increased the quotient value.It is concluded that the phosphogluconate-oxidative pathway, if active at all in chicken liver, plays a subordinate role in carbohydrate metabolism in this tissue compared with its role in carbohydrate metabolism in rat liver.


1968 ◽  
Vol 108 (4) ◽  
pp. 655-661 ◽  
Author(s):  
Alan G. Goodridge

Incorporation of [U−14C]glucose into carbon dioxide, glycogen, cholesterol and fatty acids and of 3H2O into cholesterol and fatty acids was measured in liver slices from embryos and growing chicks. During the embryonic period, rates of incorporation were low and stable for all pathways. Fatty acid synthesis and glucose oxidation increased promptly when the chicks were fed, reaching plateau levels within 6 days. Cholesterol and glycogen synthesis increased only slightly when the birds were fed. After 5 and 11 days respectively, cholesterol and glycogen synthesis began to increase rapidly. The rate of glucose oxidation in liver slices from 4-week-old chicks was 20-fold greater than in slices of embryonic liver; glycogen, cholesterol and fatty acid synthesis had increased approximately 100-, 300- and 1000-fold respectively. The increase in the metabolism of [U−14C]glucose that occurred after hatching was probably due to the change from a high-fat non-carbohydrate diet (yolk) to a high-carbohydrate low-fat diet (mash).


2007 ◽  
Vol 115 (S 1) ◽  
Author(s):  
K Stadlbauer ◽  
B Brunmair ◽  
Z Szöcs ◽  
M Krebs ◽  
A Luger ◽  
...  

1965 ◽  
Vol 48 (2) ◽  
pp. 263-271 ◽  
Author(s):  
Herbert Schriefers ◽  
Gerlinde Scharlau ◽  
Franzis Pohl

ABSTRACT After the administration of anabolic steroids to adult female rats in daily doses of 1 mg per animal for 14 days, the following parameters were investigated: the rate of the Δ4-5α-hydrogenase-catalyzed cortisone reduction in liver slices and microsomal fractions, the adrenal weight and the in vitro corticosterone production rate. Among the steroids tested, only 17α-methyl-testosterone and 17α-ethyl-19-nor-testosterone were effective in lowering significantly cortisone reduction rate by liver slices with concomitant decreases in microsomal Δ4-5α-hydrogenase-activity. Testosterone, 19-nor-testosterone, 17α-ethinyl-19-nor-testosterone, 17α-methyl-17β-hydroxy-androsta-1,4-dien-3-one and 1-methyl-17β-hydroxy-androst-1-en-3-one were ineffective or only slightly effective. Adrenal weight and absolute corticosterone production rate (μg/60 min per animal) were decreased after treatment with 17α-methyl-testosterone, 17α-ethyl-19-nor-testosterone and 1-methyl-17β-hydroxy-androst-1-en-3-one. Corticosterone production was decreased with 17α-ethinyl-19-nor-testosterone in spite of an unchanged adrenal weight. The relative corticosterone production rate (μg/60 min · 100 mg adrenal) was in any cases unaffected. According to these results there exists – with the exception of 17α-ethinyl-19-nor-testosterone – a strict parallelism between corticosteroid turnover and corticosterone production rate: unchanged turnover is correlated with unchanged corticosterone production rate, while a decreased turnover is correlated with decreased adrenal activity. The protein-anabolic effect of certain anabolic steroids may be partly due to an anti-catabolic action of these compounds resulting from a decreased corticosteroid inactivation and production rate. Possible mechanisms by which anabolic steroids may affect corticosteroid-balance are discussed.


1971 ◽  
Vol 67 (3) ◽  
pp. 517-530 ◽  
Author(s):  
Martin Wenzel

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.


1960 ◽  
Vol XXXIII (IV) ◽  
pp. 532-538 ◽  
Author(s):  
H. Breuer ◽  
Gerta Pangels
Keyword(s):  

ABSTRACT The metabolism of oestrone, oestradiol-17α and oestradiol-17β has been studied in rabbit liver slices. Oestradiol-17α and oestradiol-17β were isolated as metabolites of oestrone. When oestradiol-17α17α was incubated oestrone and oestradiol-17β were formed, whereas oestradiol-17β gave rise to oestradiol-17α and oestrone. Quantitative experiments showed that after incubation of oestrone 5–8 times as much oestradiol-17β was found as oestradiol-17α.


1997 ◽  
Vol 78 (5) ◽  
pp. 805-813 ◽  
Author(s):  
Kjell Holtenius ◽  
Paul Holtenius

The metabolic effects of a phlorizin-induced drainage of glucose were studied in six lactating ewes with or without peroral alanine drenches in a study of crossover design. Phlorizin gave rise to a small, but significant, elevation of plasma β-hydroxybutyrate. The plasma level of alanine decreased by about 30 % due to the phlorizin injections and alanine was negatively correlated to β-hydroxybutyrate. The plasma level of free fatty acids increased due to phlorizin. Plasma insulin and glucose concentrations were not significantly affected by phlorizin while glucagon level showed a small but significant increase. Peroral alanine drenches to phlorizin-treated ewes gave rise to a transitory elevation of alanine in plasma. The plasma level of free fatty acids was about 40 % lower in phlorizin-treated ewes receiving alanine and β-hydroxybutyrate tended to be lower (P < 0.08). We suggest that β-hydroxybutyrate, apart from its function as an oxidative fuel, might play an important role by limiting glucose oxidation and protein degradation in skeletal muscles during periods of negative energy balance in ruminants. Furthermore, it is suggested that alanine supplementation decreases lipolysis and ketogenesis in lactating ewes.


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