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M Kirchgessner

Publications and source records attributed to M Kirchgessner.

At least 217 records · Page 12Linked to original sources
PubMed1981

[Protein supply of rats and transaminase and succinate dehydrogenase activity].

The influence of an isocaloric diet containing 13 and 20% of crude protein on the activities of GOT, GPT and succinic dehydrogenase in rat livers was determined and compared to the growth as well as to the body composition of the animals. The weights of the animals were significantly increased, feed efficiency and consumption of metabolizable energy per gram of body increase were much better with higher protein supply. It may be concluded that protein retention was better while fat retention was nearly unaffected. The activities of the liver enzymes increased with the protein content of the diet, especially GOT 1,8 times and succinic dehydrogenase 3 times as compared to the respective values of the lower protein group. It is discussed that the activity of succinic dehydrogenase represents a suitable criterion for the evaluation of a changed metabolism, especially when protein supply is marginal.

Alanine Transaminase↗
PubMed1981

[Effect of various enzyme-substrate ratios on trypsin activity in the presence of trace elements].

In vitro experiments were conducted with trypsin and Na-Benzoyl-l-arginine-p-nitroanilid (L-BAPA) as substrate. The aim of the work was to explore the influence of additional Cu2+, Zn2+, Co2+, Ni2+ and Fe3+ ions in the reaction mixtures on the trypsin activity at different enzyme-substrate ratios (E : S = 1 : 100; 1 : 50; 1 : 10; 1 : 5). The reaction conditions were chosen according to the steady-state conditions of the tryptic hydrolysis. The trypsin activity increased by adding small amounts (4.5 X 10(-7) mol Cu2+/l) and decreased by adding higher amounts of Cu2+ ions. There was no influence of the E : S ratio. The tryptic activity was only partly influenced by the substrate concentration when the other trace elements were added to the reaction mixtures. These results may explain in part the improved protein digestibility which is reported when 250 mg Cu/kg are added to pig feeds.

Arginine↗
PubMed1981

[Influence of age and sex on in vitro intestinal absorption of zinc and manganese].

The influence of age and sex on the intestinal in vitro absorption of the trace elements zinc and manganese was studied with SPF-Sprague-Dawley-rats. For this purpose the absorption was measured with animals of both sexes starting at once after the weaning period (17 to 20 days) until an age of maximal 80 days. The measurements were made continuously in periods of a few days. The results of a total of five experimental series show that the transfer to the serosal solution and the uptake of the intestinal wall of both elements decrease permanently with increasing age. The most severe decrease occurs, however, at an age of the rats between 20 and 40 days, that is shortly after the weaning period. The previous change of the diet, however, cannot be the main explanation for the significant alteration of the absorption. In order to test this possibility the rats were only fed with the milk of their mothers up to an age of 36 days, while the control groups received already a pelleted casein diet starting with an age of 18 days. The results of these experiments were that the milk-fed rats absorbed only somewhat more zinc or manganese than did the corresponding control groups. There were no significant differences in the amounts of Zn absorption between male and female rats.

Age Factors↗
PubMed1981

[Effect of Cu++ ions on the activity of trypsin on natural substance].

In vitro experiments were carried out in order to investigate the influence of Cu++-ions on the tryptic hydrolysis of casein and soybean protein. The admixture of 10(-3) to 10(-2) Mol Cu++/l to the reaction preparations results in the activation of trypsin in both substrates. The further increase of the Cu++-concentration results in a decrease of the trypsin activity and, with casein as substrate, in trypsin inhibition. The effects are similar with the synthetic substrate N alpha-benzoyl-L-arginine-p-nitroamilide (L-BAPA), however, trypsin is already activated after the admixture of approximately 5 x 10(-6) Mol Cu++/l. Since the admixture of Cu++-ions in experiments with pepsin in similar concentrations as with trypsin also results in an activation, the question is being discussed whether the improved protein digestibility and the higher weight increase of pigs which received 250 ppm copper can be traced back to these effects.

Benzoylarginine Nitroanilide↗
PubMed1981

[Effect of inhibition of intestinal glucosidase on protein and energy balance in rats].

In a two-factorial balance trial two dietary protein levels of 12 and 15% the effect of a supplement of 50 mg alpha-glucosidase inhibitor (Bay g 5421) per kilogram food on nutrient digestibility, protein, and energy balance was tested in growing rats. At both protein levels the alpha-glucosidase inhibitor reduced the apparent digestibility of protein by maximal 8 and 4%, those of starch and energy only by 3 and 1%, respectively. With the low protein supply the protein and energy retention was decreased each by 13% when the inhibitor was given. On the basis of metabolizable energy, 6 and 19% less energy in form of protein and fat, respectively, have been deposited compared with the control group. These results may indicate also an effect of the glucosidase inhibitor on the intermediary metabolism.

Acarbose↗
PubMed1981

[Hematologic changes in nutritional lead deficiency].

In the present experiments hematological changes could be induced in growing rats by alimentary lead deficiency. The lead-depleted mothers of different generations had already shown a trend to lower values of hematocrit and mean corpuscular volume in comparison with control mothers. In young male rats of the F1-generation from lead-depleted mothers hematocrit was reduced by about 22%, hemoglobin by about 25%, the mean corpuscular volume by about 23%, and the mean corpuscular hemoglobin by about 28% as determined 3 days after weaning in comparison with control rats. Depletion of female rats till the 38th day of life intensified the hematological changes: hematocrit values were reduced by about 14%, hemoglobin by about 32%, the mean corpuscular volume by about 29%, mean corpuscular hemoglobin by about 37%, and the mean corpuscular hemoglobin concentration by about 12%. In the F2-generation rats of the depletion group always showed changed hematological values in comparison with control animals. Hematological changes normalized by repletion starting from the day of birth (crossing-over experiment) or the day of weaning (depletion-repletion experiment). In the crossing-over experiment, in which one half of the littermates of the lead-depleted mother and of a control mother were changed among one another on the day of birth, it could be shown that depletion during the fetal stage was decisive for development of hematological changes. Overall, the reproduced hematological changes resulting from lead depletion and their normalization after repletion are- besides the growth depression- a proof of the essentiality of lead.

Anemia, Hypochromic↗
PubMed1981

[Alpha amylase and dehydrogenase activity in suboptimal Ni intake].

Supplementary to studies on the activity of various enzymes during Ni deficiency, the present work was done to determine their response to suboptimal Ni supply. Live weight gain of rats was not affected by 60 versus 150 ppb Ni in the diet. The activity of alpha-amylase, however, was reduced by 43% in the case of 60 ppb dietary Ni and in relation to the change in this enzyme the activity of glucose-6-phosphate dehydrogenase by 56% and of the lactate dehydrogenase by 27%. These dehydrogenases responded with increased activities to the slight raise in Ni supply with the diet containing 150 ppb Ni as compared to the group given 60 ppb dietary Ni. Overall, it may be inferred that growth is not affected unless dietary Ni supply is below 50 ppb and that dietary Ni contents of 60 and 150 ppb must be regarded as suboptimal supply levels because of the diminished activity of various enzymes.

Amylases↗
PubMed1981

[Effect of a 2-day increased energy supply on heat production and energy utilization in full-grown sows].

In a respiration trial with 12 nongravid, nonlactating sows, the effect of supplying energy at greatly discrepant levels for 2 days (18, 45, 4.5 and 4.5 g feed/kg 0.75 per meal) on parameters of energy metabolism was studied in comparison with a consistent feed intake (18 g feed/kg 0.75 per meal). The trial was conducted as a change-over design (AB - BA) and included a total of 24 balance periods. The isoenergetic nutrition was aimed at the maintenance energy level. Digestion coefficients for dry matter, nitrogen, carbon and energy were not affected by the inconsistent distribution of the feed supply. Similarly, all parameters of energy metabolism in the sum of the 2-day periods were not different between the two treatments. The maintenance energy exchange averaged 49.1 MJ/2 . days when the energy supply was inconsistent and 48.4 MJ/2 . days in the control group. In the course of the 48-hour measurements, heat production during inconsistent energy supply was higher by 1.8 MJ on the 1st day and 1.2 MJ lower on the 2nd day than in the control group. The additional energy of 17 MJ (75%) supplied in treatment B on the 1st day above that in the control did not seem to have been stored by fat synthesis within this time.

Animals↗
PubMed1981

[Intestinal absorption of vitamin B6 in vitro in response to the mucosal concentration of pyridoxine . HCl (author's transl)].

The in vitro absorption of vitamin B6 from the mucosal to the serosal solution was studied, using everted sacs of the proximal jejunum of male rats. The concentration and the absorbed amount of vitamin B6 in the intestinal wall and in the serosal solution was measured after an incubation of 45 minutes with 0, 2, 4, 10, 25, 50, 100, 200, 500 micrograms pyridoxine . HCl (PN . HCl) per ml mucosal solution. The concentration and the absorbed amount of vitamin B6, increased linearly with the mucosal concentration of PN . HCl. This could be found for the results of the serosal solution as well as for the results of the intestinal wall, which increased, however, more than those of the serosal solution. The passive diffusion was confirmed as mechanism of the absorption of vitamin B6. Besides, it could be concluded from these results that a homeostatic regulation of vitamin B6 is not due to the mucosal to serosal absorption.

Animals↗
PubMed1981

[Retention, absorbability and metabolic efficiency of iron in lead depleted rats (author's transl)].

In lead-depleted rats retention, absorbability and metabolic efficiency of iron were determined. In comparison with control rats in lead-depleted rats, whose mothers were already depleted, the whole iron retention of the organism as well as the iron retention of selected organs were heavily reduced. Also the iron absorbability of lead-depleted rats was impaired whereas the metabolic efficiency of iron was higher than in control rats. The interactions between iron and lead indicate a function of lead in iron absorption.

Animals↗