PubMed Health⌕ Search

Biomedical subjects

A Vyskocil

Publications and source records attributed to A Vyskocil.

At least 55 records · Page 3Linked to original sources
PubMed1988

A subchronic inhalation study with unleaded petrol in rats.

The effect of intermittent 2 months' exposure to 2 g/m3 unleaded petrol on the hypothalamo-pituitary-thyroid-adrenal system was evaluated by measuring hypothalamic noradrenaline (NA), serum corticosterone (CS), thyroxine (T4) and adrenal catecholamine (CA) levels in male rats. Serum CS and adrenal CA were increased and hypothalamic NA was decreased by exposure. No changes were observed in serum T4. Exposure induced an increase in spleen, kidney, liver and lung weights; weights of adrenals and hypothalamus were not changed. All the petrol-induced effects depended on the length of exposure. Rats exposed to petrol gained less weight than controls. The results suggest a non-specific stress response in the rat.

Administration, Inhalation↗
PubMed1988

Hormonal and organ weight changes in rats exposed to simultaneous chronic effects of CO and NO2.

UNLABELLED: Activity of the pituitary-adrenocortical, sympathico-adrenomedullary and thyroid gland systems was examined in groups of male adult rats, average weight 180 g, exposed for 2 months to a mixture of 7 mg.m-3 NO2 and 32 mg.m-3 CO in air and in groups of matched controls inhaling fresh air. Corticosterone (B) concentrations in the serum of rats were determined by the competitive protein-binding method, noradrenaline (NA) in the hypothalamus and catecholamines (CA) in suprarenals by fluorometry, thyroxine (T4) and triiodothyronine (T3) in the thyroid gland by the RIA technique. Measurements of organ weight were related to overall body weight. The data emerging from this study were evaluated using the Student t-test. CONCLUSIONS: one-month exposure led to a decrease in hypothalamic NA and an increase in rat spleen weight; increase in CA concentration in the adrenals was initially insignificant, by the end of a 2-month exposure it reached the level of statistical significance; serum concentrations of B, T3 and T4 remained unaffected and so was the weight of the body, liver, lungs, suprarenals and the hypothalamus of exposed rats; at the concentrations used, NO2 and CO acted as synergists producing a mild stressogenic reaction affecting the activity of the sympathico-adrenomedullary system of exposed rats.

Animals↗
PubMed1986

The effect of carbon monoxide on hormone levels and organ weights in rats.

Male Wistar rats were exposed continuously for 1 or 2 months to 25 or 100 ppm CO. The concentrations of noradrenaline in the hypothalamus, corticosterone and thyroxine in serum and of adrenal catecholamines were estimated. After exposure to 25 ppm CO no significant changes were observed in the serum corticosterone and thyroxine, hypothalamic noradrenaline, adrenal catecholamines levels, or in the weights of lung, spleen, adrenal glands, liver and the whole body. Exposure to 100 ppm CO induced a decrease in hypothalamic noradrenaline and serum thyroxine and an increase in adrenal catecholamines and serum corticosterone. Whole-body and organ weights were unchanged except for a slight decrease in liver weight. The results suggest a non-specific stress response in the rat to 100 ppm CO whilst concentration of 25 ppm CO was without any stress effect.

Adrenal Glands↗
PubMed1985

The effect of chronic exposure to 3.5 ppm NO2 on hormone levels and organ weights in rats.

Male Wistar rats were exposed continuously for 1 or 2 months to 3.5 ppm NO2. Levels of histamine and serotonin in lung, noradrenaline in hypothalamus, corticosterone and thyroxine in serum and catecholamines in the adrenals were estimated. No significant changes were observed in lung histamine and serotonin, serum corticosterone, or adrenal catecholamine levels; or in the weights of lung, spleen, adrenal glands, hypothalamus, liver and the whole body. The only significant change was a decrease in the concentration of hypothalamic noradrenaline after 2 months of exposure. The results suggest that prolonged exposure to 3.5 ppm NO2 does not result in changes in hormone levels, organ and body weights, and therefore does not precipitate pulmonary defensive reactions or non-specific stress response.

Adrenal Glands↗
PubMed1983

The effect of chronic exposure to 100 ppm carbon monoxide on brain biomines, serum corticosterone and organ weights in rats.

The effect of chronic exposure to 100 ppm (0.01%) CO on pituitary-adrenal activity was evaluated by measuring serum corticosterone and brain bioamine levels in the rat. Exposure to CO for 1 month induced a decrease in the brain serotonin levels. Serum corticosterone, brain dopamine and noradrenaline as well as the weight of the adrenal glands, lungs, spleen and liver were unchanged. After two months of exposure, serum corticosterone and brain serotonin levels were elevated and the liver weight was significantly lower. This suggests that at this chronic low concentration CO acts as a stressor, and the organism initiates a general defensive reaction. The effect of CO on the pituitary-adrenal axis could be mediated by a central neuronal pathway.

Animals↗
PubMed1983

Importance of the functional state of alveolar macrophages of the lungs for hygienic evaluation of protective reactions and cell damage due to atmospheric pollution.

Total number of cells, their viability and ability to adhesion were examined in surface alveolar macrophages isolated from rat livers after exposure to sulphur dioxide during 2, 4 and 6 weeks (0.05, 0.5, 1.0 and 5.0 mg/m3); to nitrogen oxide during 5, 8 and 15 hours, 28 and 56 days (19 mg/m3) and to carbon monoxide during 2, 28 and 56 days (0.01% or 10 MAC). In the experiment with exposure to sulphur dioxide, the activity of enzymes of varying localization in the macrophages - soluble in the cytoplasm (lactate dehydrogenase) and connected with subcellular structures - lysosomes (beta-galactosidase, beta-glucosidase and acid phosphatase) was tested by means of biochemical methods in parallel with cytological examinations. Low concentrations of various chemical contaminants of the atmospheric air (sulphur dioxide, nitrogen oxides, carbon monoxide) have an unfavourable biological effect on rats, manifest in the impairment of local immunity, i.e., decreased number of alveolar macrophages, disturbance of their viability and reduced ability of the macrophages to adhesion. At the same time, sulphur dioxide induces enzyme disorganization in lactate dehydrogenase and in a number of lysosomal enzymes of the macrophages. These results serve as a basis for the recommendation of cytobiochemical methods of elaborating methodological approaches to the regulation of environmental factors. Alveolar macrophages as a constituent part of the mononuclear phagocytic system ensuring local non-specific and specific resistance of the organism form one of the most important cellular mechanisms of protection of the organism against the harmful effect of environmental factors including chemical contaminants of the atmospheric air (1, 2).(ABSTRACT TRUNCATED AT 250 WORDS)

Acid Phosphatase↗
PubMed1981

Determination of beta 2-microglobulin in human urine and serum by latex immunoassay.

This highly sensitive method for determination of beta 2-microglobulin (beta 2-m) in human urine or serum is based on direct agglutination by beta 2-m of latex particles on which an antibody against beta 2-m is adsorbed. The agglutination is quantified by counting the remaining unagglutinated particles, or by turbidimetry. A novel aspect of this method is the capability to prevent nonspecific agglutination of the antibody-coated particles by diluting them with an albumin solution of well-defined characteristics (pH, freshness, concentration) just before the assay. The assayable concentration range is 1--32 micrograms/L, the detection limit 0.5 micrograms/L. Within-assay CV, based on 10 determinations of beta 2-m in urine and serum at two different dilutions, ranged from 4.6 to 8.7%. Between-assay CV, calculated from 10 determinations of beta 2-m in urine and serum, was 10 and 8.4%, respectively. Analytical recovery of beta 2-m in urine averaged 97% and in serum 104% (n = 10). No component of urine or serum interfered. Coefficients of correlation for beta 2-m in urine or serum as measured by radioimmunoassay and latex immunoassay were 0.97 and 0.93, respectively. Concentrations of beta 2-m in serum and urine from 33 healthy men (ages 20 to 67 years) averaged 1.5 mg/l and 54 micrograms/g of creatine, respectively.

Agglutination Tests↗