The effect of branched chain amino acids on protein synthesis in two skeletal muscles of Japanese quail.

Two different isolated skeletal muscles of Japanese quail were used. The influence of branched chain amino acids on the fractional rate of protein synthesis (FSR) was evaluated using 14C-tyrosine. The addition of 0.5 mM valine, leucine or isoleucine to the incubation medium significantly decreased (P<0.05) the value of FSR in extensor metacarpalis radialis. In the ambiens muscle only the application of leucine increased the FSR significantly while valine and isoleucine were without any effect.

Activity of ornithine decarboxylase in muscle of Japanese quail in hypergravity conditions.

Ornithine decarboxylase (ODC) is the rate limiting enzyme in the synthesis of polyamines which are generally required for animal cell proliferation. Because of many different stimuli changing the activity of ODC, the effect of hypergravity on muscle ODC activity in Japanese quail was investigated. Adult Japanese quail cockerels were exposed to 2G in the centrifuge permanently for 96 hours. The activity of ODC was determined by radioisotopic method in supernatant of homogenised breast and fibular muscles (m. pectoralis minor, m.superficialis fibularis). The activity of ODC was higher in breast muscle than in the fibular muscle in both, control and experimental groups. Exposition of quail to hypergravity evokes approximately 2 fold increase of ODC activity in both breast and fibular muscles. The results suggest that 96 hours of permanent hypergravitation (2G) caused activation of polyamine synthesis and their involvement in biochemical processes of adaptation to hypergravity.

[Forms of xanthine oxidoreductase in the tissues of Japanese quail]. / Formy xantin oxidoreduktázy v tkanivách japonskej prepelice.

The Japanese quail tissues--liver, kidney and pancreas were analysed for the presence of forms of xanthine oxidoreductase utilised cofactors NAD+, molecular oxygen or artificial acceptor--methylene blue, as well as for the validity of correlation between enzymatic activity and diet protein content. Four groups of animals with the experimental diets, the formulae of which are given in Tab. I, and control group with a commercial mash were fed for ten days. For enzyme preparation, the rough purification of cytoplasmic fraction with subsequent dialysis was used. The xanthine oxidoreductase utilised NAD+ (XOR-NAD) was detected in all examined tissues (Fig. 1), whereby the correlation of enzymatic activity with diet protein content was shown only in liver, according our previous findings (Jankela; 1978; Baranovská and Gazo, 1990). The values in liver and pancreas of animals fed a commercial mash were somewhat out of the range of linearity, probably because of the presence of nonprotein substances in mash, which affected the XOR activity in these organs (Jankela, 1992). The XOR utilised O2 (Fig. 2) was only detected in liver and kidney with certain activity in animals fed free protein diet. The percentage of this enzyme form was below 18% of the total activity (Fig. 5). The xanthine oxidoreductase utilised methylene blue (XOR-MM) was detected in liver, kidney and pancreas (Fig. 3). The correlation of enzymatic activity with diet protein content was linear in liver and kidney. The percentage of XOR-MM activity was very high, it amounted to 55% of the total activity (Fig. 4).(ABSTRACT TRUNCATED AT 250 WORDS)

Nitrogen excretion in Japanese quail during protein depletion and repletion.

The influence of protein depletion and repletion on the excretion of uric acid, urea, creatinine and free arginine as well as on the activities of xanthine dehydrogenase and arginase in Japanese quail was studied. Adult cockerels normally fed until the age of 42 days were kept on a protein free diet for 21 days and subsequently for 14 days on the previous normal diet. The control group was fed normal diet for the whole time. In 1-5 days intervals the enzyme activities and the N-metabolites in 24 hours excreta were determined. Protein free diet feeding evoked rapid (in term of 8-9 days) diminution of the excretion of N-metabolites, as well as of the xanthine dehydrogenase activity up to the fourth-tenth part of the initial values. The arginase activity was not influenced by this treatment. Body mass decreased by 36%. Returning to the normal protein feeding reverse the values of observed parameters to their initial levels within 8-9 days. It was concluded that changes in excreted N-metabolites caused by protein free feeding were rapid and recoverable by returning to normal diet.

[The effect of fatty acids in the feed on xanthine dehydrogenase activity in the Japanese quail]. / Vplyv mastných kyselín v krmive na aktivitu xantin dehydrogenázy u prepelice japonskej.

The aim of the present study is to determine the effect of different fatty acids on the amino acid catabolism judged on the level of xanthine dehydrogenase (XDH). The model system of protein depletion with subsequent repletion was used in the trial consisted of Japanese quails 71 days old. In the period of protein repletion, the fatty acid (stearic, palmitic, oleic, linolenic, linoleic and lauric, respectively) was used instead of common fatty compound in the diet. Specific activities of XDH in liver, kidneys and pancreas of quails were tested dynamically from the first to the eighth day of feeding. It was demonstrated that neither lauric, palmitic nor oleic acid, respectively, had an effect on the development of the specific activity of XDH (Fig. 3). Stearic acid as a sole fatty compound in the diet however evoked reactibility of XDH in liver or in pancreas in different way as in kidneys (Fig. 4). The dynamics of the XDH development in kidneys was practically identical than that in the control. However, XDH in liver and pancreas raised statistically already from the first day of feeding. The effects of linoleic and linolenic acids on the development of specific activity of XDH were organ selective, too (Fig. 5). XDH in kidneys was shown in the same manner as in the control group. In liver and pancreas, however, the specific activity of XDH was diminished markedly just from the first day of feeding.

[The effect of dietary lysine excess and deficiency on metabolism in Japanese quail]. / Vplyv nedostatku a nadbytku lyzínu v diéte na metabolizmus prepelice japonskej.

We conducted three experiments with Japanese quail to study the influence of deficient and excessive contents of lysine in the feed in relation to certain zootechnical parameters, protein value, to the active of liver xanthine dehydrogenase, content of free plasma lysine under the conditions of the maximum saturation of blood pool, and to the changes in 14C-labelled lysine degradation. The zootechnical parameters and protein value were optimum at the content of 5.22 g Lys per 16 g nitrogen in the feed, the activity of liver xanthine dehydrogenase was maximum. In a separate experiment the maximum saturation of blood pool determined with respect to a lysine supply in the feed reached the highest value at 6.88 g Lys per 16 g nitrogen and it decreased later on although the lysine supply increased. We assume the existence of a regulating mechanism that does not allow exceeding certain lysine concentrations in the blood plasma. Lysine degradation measured by the value of 14CO2 expired from 14C-labelled lysine was higher both with lysine deficient and excessive content, than with the lysine content in the feed approaching the required value.

[Postnatal development of enzyme activities of nitrogen catabolism in the liver of Japanese quail]. / Postnatálny vývoj aktivít enzýmov katabolizmu dusíka v peceni japonskej prepelice.

In the course of postnatal development from the hatching up to the age of 84 days, the activities of xanthine dehydrogenase (XDH), glutamate dehydrogenase (GLDH) and arginase were examined in the liver of Japanese quail. The observation in weekly intervals showed a gradual character of XDH development whereas the conclusion of the first degree correlated to some extent with the period of achieving the sexual maturity of animals. The GLDH activity increased in the course of the growth with attainment of the maximum value in the same period. The course of the development of hepatic arginase activity indicated the potential changes of this enzyme.

[Effect of accelerations, additional weight load and hypokinesia on protein catabolism in the Japanese quail (Coturnix coturnix japonica)]. / Vliianie uskorenii, dopolnitel'noi vesovoi nagruzki i gipokinezii na katabolizm belkov u perepela iaponskogo (Coturnix coturnix japonica)

Activities of glutamate and xanthine dehydrogenases were measured in four groups of quails (coturnix coturnix japonica): 1) hypodynamic birds which were kept in an area which made 1/4 of the control, 2) birds exposed to an increased weight load, 3) birds exposed to 3g. and 4) control birds. The experimental birds were exposed to the above treatment for 1 to 6 hours a day during 8 days. The birds were fed on a forced basis to eliminate differences in food intake. The activity of glutamate dehydrogenase was measured in the liver and that of xanthine dehydrogenase was assayed in the liver, kidneys and femoral muscle. It was found that increased gravity, weight load and hypodynamics affected the first and last stages in protein catabolism.