Search PubMed⌕ Search

Biomedical subjects

R Hampl

Publications and source records attributed to R Hampl.

At least 109 records · Page 6Linked to original sources
PubMed1988

Steroid-protein adduct in the lens of chicken embryo following application of prednisolone esters.

Protein--prednisolone adducts were detected by semiquantitative radioimmunoassay in both water- and urea soluble fractions of homogenates from lenses of chicken embryos, given systemically single doses (100 microliters each) of four prednisolone esters. The findings were correlated with macroscopic changes of lens transparency. The highest concentrations of protein-associated immunoreactive material were found after prednisolone sulphate application, associated with the most apparent loss of transparency.

Animals↗
PubMed1987

Radioimmunoassay of epitestosterone: methodology, thermodynamic aspects and applications.

A radioimmunoassay system for 17 alpha-hydroxy-4-androstene-3-one (epitestosterone) was developed and evaluated using rabbit antisera against 17 alpha-hydroxy-4-androstene-3-one-3-(O-carboxymethyl)-oxime-bovine serum albumin conjugate, and radioiodinated homologous histaminyl derivative of epitestosterone as a tracer. Two antisera with different specificity were used for radioimmunological determination of epitestosterone in hydrolyzed urine and plasma, respectively. Apparent intrinsic association constants and derived thermodynamic variables for ligand-antibody interaction were measured under various conditions in order to set up an optimal assay protocol. The mean plasma epitestosterone levels for healthy subjects were 0.44 +/- 0.15 nmol.l-1 (means +/- SD) in males and 0.092 +/- 0.056 nmol.l-1 in females. The corresponding concentrations in urine were 320 +/- 70 nmol.l-1 (males) and 273 +/- 100 nmol.l-1 (females).

Body Fluids↗
PubMed1987

Influence of trifluoperazine on ACTH- or angiotensin-stimulated mineralocorticoid and glucocorticoid secretion in man.

During stimulation of adrenocortical secretion the calcium--calmodulin system is activated to a different extent, depending on the secretagogue substance. In the submitted paper the influence of therapeutic doses of the calmodulin inhibitor, trifluoperazine, on aldosterone and cortisol secretion stimulated by ACTH or by activation of endogenous angiotensin by furosemide was investigated in healthy subjects. Trifluoperazine already in amounts of 6 mg/day administered for one week inhibited the "basal" aldosterone secretion assessed in a vertical position (p less than 0.01) and ACTH stimulated secretion (during the 30th minute p less than 0.05). The basal aldosterone secretion assessed in a horizontal position was not affected by trifluoperazine, similarly as it did not affect the secretory response to endogenous angiotensin activated by furosemide, regardless whether a dose of 6 mg or 12 mg/day was used. ACTH stimulated cortisol blood levels were after trifluoperazine insignificantly but constantly lower throughout the test, while they were not altered by trifluoperazine in the furosemide test. The plasma calcium level was not significantly affected by trifluoperazine. It may be concluded that trifluoperazine alters ACTH stimulated mineralocorticoid secretion, while it does not influence angiotensin stimulated secretion. The revealed differences in adrenocortical response to trifluoperazine in vivo cannot be explained merely by a different sensitivity of the calcium-calmodulin system to stimulation by two different secretagogues, but by interaction of some regulatory mechanisms influenced by trifluoperazine with adrenocortical secretion.

Adrenal Cortex↗
PubMed1987

Radioimmunoassay of 11 beta-hydroxyandrostenedione in laboratory diagnostics of selected endocrine disorders.

A specific radioimmunoassay of 11 beta-hydroxy-4-androstene-3,17-dione, an androgen of exclusively adrenal origin, is described and evaluated. The antiserum was raised in rabbits using 6 beta,11 beta-dihydroxy-4-androstene-3,17-dione-6 beta-hemisuccinate:bovine serumalbumin conjugate as an immunogen. The method has been used for determination of the plasma levels of the hormone in healthy subjects, including children, with regard to the possibility its use as a laboratory marker for monitoring corticoid therapy in patients with congenital adrenal hyperplasia and in patients with various endocrine disorders, under basal conditions and after dynamic tests. The plasma levels of 11 beta-hydroxyandrostenedione (means +/- s.d.) in healthy persons at 8 a.m. were 8.69 +/- 2.88 (men), 7.72 +/- 2.85 (women), 8.73 +/- 5.13 (boys) and 7.88 +/- 5.23 (girls) nmol/l, respectively. The hormone concentrations followed the pattern of circadian rhythm of cortisol, they were increased markedly after corticotropin and suppressed by dexamethasone.

Adolescent↗
PubMed1987

Changes in cortisol level in saliva following relaxation-activation autoregulative intervention.

The relaxation-activation autoregulative method (RAM) is a psychoregulative procedure characterized by typical autonomic patterns of relaxation and activation phases (blood pressure, electric skin resistance, heart beat, EEG, etc.). They are used as feedback information in the training of autoregulative abilities. RAM has a multidimensional (non-specific) tuning effect which is manifested by changes in the psychophysiological state (emotional tuning, physiological functioning and performance). It has a therapeutical effect on disorders with a psychic pathogenic component, e.g., essential hypertension. The increased production of adrenaline following the application of RAM was found in previous experiments.--The present experiment with a sample of six persons well mastering RAM has shown that the cortisol level following this psychoregulative intervention also rises significantly and that this rise has been recorded over three days, i.e., over the whole period of saliva sampling. It may be said that RAM has a non-specific, ergotropic (activating) subsequent effect and that this effect has the character of stress, more accurately eustress. Autogenic training, on the other hand, reduces the cortisol level.

Autonomic Nervous System↗
PubMed1987

[Transport and intracellular distribution of components of the cortisol-asialotranscortin complex in the liver].

The effect of desialation of human transcortin on the transcortin-cortisol complex transport into hepatocytes and on subsequent intracellular distribution of the complex components was studied in model experiments with perfused rat liver. It was demonstrated that in the presence of desialated transcortin the time of [3H]cortisol incubation in the perfusion medium decreased more than 200 times as compared with the native protein. [3H]cortisol and [131I]asialotranscortin trapping by hepatocytes occurs simultaneously. The content of the [3H]cortisol--[131I]asialotranscortin complex in rat liver plasma membranes reaches a maximum 3 min after beginning of perfusion. Then the intact complex is transported into lysosomes, where it dissociates with a subsequent release of asialotranscortin and cortisol metabolites into the cytoplasm.

Animals↗
PubMed1987

Effect of etomidate on adrenal function in rats.

Etomidate, an imidazole derived hypnotic was applied to rats in order to find out whether repeated treatment with the drug, in doses exceeding those usually given to human, does alter adrenal morphology and function in terms of corticosterone and 11 beta-hydroxyandrostenedione (an androgen of exclusively adrenal origin) production, both in vivo and in vitro. A slight, dose-related decrease of plasma corticosterone and 11 beta-hydroxyandrostenedione was observed from etomidate concentrations 0.3 resp. 1.4 mg kg-1 body weight, respectively. In vitro, corticosterone production was reduced in the groups receiving 0.7 mg of the drug or more. Morphologically, only minute lipid hyperplasia was found after the highest dose of etomidate, associated with a significant increase of relative body weight. Administration of low dose of etomidate (approx. one half of that given usually to human) led to an increase of corticosterone production, indicating the reversibility of such effect. Etomidate did not stimulate enzymic oxidation of 11 beta-hydroxysteroids to the corresponding 11-oxosteroids, as do some blockers of 11 beta-hydroxylase.

Adrenal Glands↗
PubMed1986

The role of corticosteroids in the homeostasis of the eye.

Three problems were studied on the human and rabbit eye: to what extent the mineralocorticoids contribute to the control of Na+ and K+ transport in the lens epithelium, how do the glucocorticoids influence the concentration of glucose in the aqueous humour and what is the effect of the pituitary-adrenal axis on the hemato-ocular barrier. Specific receptor-like proteins binding aldosterone were found in the lens epithelium. Na+ and K+ concentrations in the aqueous were influenced by both aldosterone and spironolactone administration. The aldosterone concentration in human cataracts was found to be higher in cases of cataracts complicated by arterial hypertension. In spite of some indication of anticataractogenous action of mineralocorticoids, aldosterone did not prevent the formation of cortisol-induced cataract in chick embryos. Glucose concentration in the aqueous was increased by glucocorticoid administration as well as by stimulation of their secretion by ACTH. Further, the contribution of the pituitary-adrenal axis to the breakdown of the hemato-ocular barrier was investigated by measuring the changes of the total protein content in the aqueous. ACTH1-24 caused a partial breakdown of the barrier, as well as ACTH4-10 or alpha-MSH. As the latter two peptides lack the stimulative effect on the corticoid secretion and glucocorticoids themselves fail to increase the protein content in the aqueous, the breakdown of the hemato-ocular barrier seems to be essential for ACTH-linked peptide fragments and is not mediated by corticoids.

Adrenal Cortex Hormones↗
PubMed1986

The use of andriol in treatment of androgen deficiency in transsexual women.

In search of a non-invasive, long-term acting form of androgen to be used in female-to-male transsexuals, testosterone undecanoate (Andriol, Organon) was investigated from clinical and laboratory points of view. The therapy resulted in a significant elevation of androgens with a considerable increase of the free testosterone fraction, desired virilization and somatic changes to a masculine phenotype. Testosterone undecanoate provides sufficiently high androgen levels without significant influence on the hypothalamo-pituitary-gonadal axis. The treatment impaired neither liver function nor glucose tolerance. It is concluded that this drug is suitable for hormonal preparation before the reconstructive therapy to males.

Adult↗
PubMed1986

Transport and intracellular localization of cortisol-asialotranscortin complexes in rat liver.

The influence of desialylation of human transcortin on transport of the transcortin-cortisol complex into the liver cells and its intracellular distribution was investigated in perfused rat liver. Under experimental conditions used the half-time of cortisol in perfusion medium was decreased more than 200 times in presence of asialotranscortin compared to that of native transcortin. Experiments with [3H]cortisol and [131I]asialotranscortin demonstrated a simultaneous uptake of cortisol and asialotranscortin by the hepatocytes. Distribution of [3H]cortisol and [131I]asialotranscortin in subcellular fractions showed the following pathway of cortisol-asialotranscortin complex: cell membrane, lysosomes, cytoplasm. The complex dissociates in lysosomes.

Animals↗
PubMed1986

Androgen administration to transsexual women. II. Hormonal changes.

The authors administered to six transsexual women at three-month intervals androgenic depot preparations: testosterone undecanoate (Andriol-Organon) by the oral route and testosterone isobutyrate (Agovirin depot-Spofa) in injections. The achieved changes were evaluated by clinical and laboratory examinations, i.e. somatic changes as well as changes of hormonal indicators in plasma, urine and saliva, changes in the TeBG binding capacity, the effect of the administered hormones on liver functions, glucose metabolism and secretory insulin response. The high plasma androgen level did not vary substantially. After Andriol administration, a significant decrease of plasma TeBG was achieved, and an increase of the free testosterone fraction in saliva which was retained three months after discontinuation of the treatment. Both preparations caused the required virilization, whereby the action of Agovirin depot-Spofa in the selected dose was, as regards the speed of onset and intensity of the androgenization symptoms, more effective. The gonadotropin levels were not changed significantly during short-term administration. No interference with liver functions and glucose metabolism was observed. The patients tolerated both preparations well.

Adult↗