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Biomedical subjects

K Hartmann

Publications and source records attributed to K Hartmann.

At least 199 records · Page 11Linked to original sources

[Effect of degree of experimentally induced hypothyroidism on changes in serum albumin spectra in rats].

Extreme rat hypothyreosis of identical degree was induced by radiothyroidectomy (group R-HT) and feeding of thyreostatics (groups MTU-HT and MMI-HT). External signs, growth kinetics, serum cholesterol, thyroid weight, and the iodothyrosine pattern of the thyroid glands served as references for the quality of the hypothyreotic state. Determinations of following changes (all changes significant for p less than 0.001): 1. Higher total serum protein levels in hypothyreotic rats 4 and 7 weeks after beginning the experiemnts as compared to the controls (KT). 2. After 4 weeks the relative albumin content was diminished, the relative gamma-globulin content was elevated as compared to the KT. The absolute values of albumines did not change, alpha-1-globuline and gamma-globuline contents were increased in all hypothyreotic groups. 3. After 7 weeks normal albumine values, increase of the relative and absolute alpha-1-globuline content, and decrease of the relative beta-globuline concentrations were measured. Elevated gamma-globulins were found in MMI-HT and R-HT only, and an increased absolute albumine content in MTU-HT alone. The results confirm both hyperproteinemia and dysproteinemia as characteristics of the rat hypothyreotic state. Dynamic changes of absolute and relative contents of different serum protein fractions are demonstrated in relation to the duration of hypothyreosis. This fact can possibly explain contradictory findings on type of dysproteinemia by several authors.

Animals↗

[In vitro study of deiodination of L-diiodotyrosine and L-thyroxine in liver of dietetically fat rats].

Beginning with the fifth week of life, male Wistar rats were fed a diet containing, respectively, 3 and 50 per cent fat (corresponding to, respectively, 7 and 75 per cent fat of total calories). The differences in body weight between the two groups were 64 per cent for 10-week-old rats, and 71 per cent for 6-month-old rats. For these animals, the extent of the enzymatic deiodination of L-diiodotyrosine and L-thyroxin was determined in liver homogenate supernatants. In the 10-week-old rats as well as in the 6-month-old rats on high-fat diet, the deiodination of L-di-iodotyrosine was significantly lower than in the animals on low-fat diet, whereas the diodination of L-thyroxin was significantly higher. It is concluded that the fat content of the diet exerts an inhibiting effect on the deiodination of L-di-iodotyrosine and an enhancing effect on the deiodination of L-thyroxin.

Age Factors↗

[Behavior of various blood parameters of carbohydrate and fat metabolism of light and heavy-weight rats of varying age and different diet groups].

The sera from light and heavy-weight rats varying in age and belonging to different groups on, respectively, pellets or diets containing 3% or 50% of fat were analysed for pyruvate, lactate, aceto-acetate, beta-hydroxybutyrate, free fatty acids, triglycerides and total cholesterol. There were no significant differences in these parameters between light and heavy-weight animals of the same diet group. The total cholesterol content increased with age in the rats which were fed pellets. These findings are compared with previous results of the authors and discussed in the light of recent literature.

Acetoacetates↗

[Deiodination in the kidney and thyroid function)].

In homogenate supernatants of kidneys of male rats the extent of deiodination of L-diiodotyrosine (L-DJT) and L-thyroxine (L-T4) was investigated in dependence on the thyroid function (hypo- and hyperthyroidized) and also in dependence on age. In rats hypothyroidized by loading with Methylthiouracil (MTU) or Methimazol (MMI) the deiodination for L-DJT and L-T4 was significantly reduced, in rats loaded with 40 mug T4 sc. for 10 days, the deiodination was significantly enhanced compared with untreated control animals. With advancing age (6 weeks, 3 or 12 month) the deiodination activity is highly significantly reduced. The results underline relations between thyroid gland function and deiodination activity in kidney.

Age Factors↗