Effect of carbon disulphide on the cardiovascular system.

Biochemical, histological and electron-microscopic examinations of the heart and the aorta of albino rats exposed to carbon disulphide in concentrations of 10, 50, 100 and 200 mg . m-3 were carried out. Changes in the metabolic and energetic processes in the myocardium and in the quantitative and qualitative characteristics of the connective tissue of the aortal vessel wall were observed. The established disorders follow the dose-effect dependence. The authors studied the effect of carbon disulphide in concentrations of 10 and 50 mg . m-3 on the electrophoretic spectrum of serum proteins, the quantitative and qualitative characteristics of fibrous structures in the myocardium and the aorta of albino rats fed on atherogenic diet (cholesterol, cholic acid and vitamin D2). The combination of carbon disulphide with the atherogenic factor leads to intensification of changes in the cardiovascular system and in serum proteins, observed after independent exposure to either of the factors. The combination of atherogenic diet and 10 mg . m-3 carbon disulphide induced symptoms of intoxication, decreased survival of the animals, and the developing sclerotic process was found to be more severe and to progress more rapidly than in animals subject to atherogenic diet alone. The obtained results testify to cardiovascular effect of carbon disulphide. The observed atherogenic effect of carbon disulphide in low concentrations is most probably connected with its direct effect on the myocardium and the vessels.

Effect of noise on the development of induced sclerotic processes in the rat aorta.

The authors studied the effect of 95 and 85 dB noise on the aortic wall of white rats fed for a period of 6 weeks an atherogenic diet (cholesterol + cholic acid + vitamin D2). Noise alone did not cause significant changes in the metabolism and structure of the aorta. The atherogenic diet alone caused segmental enlargement of the intercellular substance, disorganization of tissue elements, and destruction of smooth-muscle cells with marked activation of anaerobic processes, an increase in collagen content and a decrease in globular proteins and elastin. Simultaneous action of noise and of the atherogenic diet produced more pronounced biochemical and morphological alterations in the aortic wall than the diet alone. Noise not only contributes to the development of sclerotic processes but causes also complicated lesions of the aortic wall.

[Physical factors of the work environment. Changes in the aorta in experimental exposure to noise and atherogenic diet]. / Fizicheski faktori na rabotnata sreda. Promeni v aortata pri eksperimentalno shumovo vuzdeistvie i aterogenna dieta.

An experimental study was carried out on the effect of noise with intensity 85 and 95 dB on the changes in the vascular walls of albino rats of an atherogenic diet (cholic acid, cholesterol and vitamin D2) in the course of 30 daws. The single effect of noise did not induce essential deviations in aortic metabolism and structure. The atherogenic diet caused segmental increase of intracellular substance, disorientation of tissue elements, destruction of smooth muscular cells, accompanied by activation of anaerobic oxidation processes, increase of the quantity of collagenous proteins with reduced globular and elastin proteins content. The noise, with an intensity of 95 dB intensifies the alterations in the vascular wall to the origination of medionecroses.

[Morphological and biochemical changes in the connective tissue in chronic chloroacetophone poisoning]. / Morfologichni i biokhimichni prouchvaniia na suedinitelnata tukan pri khronichna intoksikatsiia s khloratsetofon.

The qualitative and quantitative characteristic of the connective tissue of aorta of albino rats was followed up, the rats having been treated with phosphororganic pesticide chloracetophon in doses I/20 and I/100 LD50 for six months. With the effect of the lower dose, disturbances were observed, affecting mainly the components of the main intercellular substance--glycoproteins and glycosaminoglycans. The higher dose leads to disturbances in the quality and quantity of the fibrous structures--elastin and collagen on the background of changed ratio sulphated GAG/non-sulphated GAG. The changes observed are an evidence for an accelerated ageing of the vascular aortic wall under the effect of chloracetophon and should be given consideration for its hygienic standardization.

[Changes of protein metabolism in experimental atherosclerosis]. / Izmeneniia obmena belkov pri éksperimental'no vyzvannykh skleroticheskikh protsessakh.

Effect of atherogenous diet (cholesterol, cholic acid and vitamin D2) on the state of collagen and elastin fibrilles as well as on content of proteins in rat blood serum, myocardium and aorta was studied by means of biochemical and histochemical methods. In sclerotic impairments the following phenomena occurred: a decrease in content of blood serum albumin, soluble tissue collagen and elastin and of insoluble elastin; an increase in content of globulins and haptoglobins in blood serum as well as of insoluble collagen in aorta and myocardium. The increase in content of insoluble collagen was accompanied by stimulation of growth of rough reticular and collagen fibrilles, deposition of calcium, fragmentation of the inner elastic membrane, by medionecrosis with deterioration of elastic tissue in aorta wall, in coronary arteria and in their intramural branches. These alterations in characteristics, properties and content of blood serum and tissue fibrillar proteins reflect only a part of complex processes involved in destruction of connective tissue under conditions of sclerosis.

[Metabolic and ultrastructural changes in the myocardium after prolonged exposure to low concentrations of carbon disulfide]. / Metabolitni i ultrastrukturni promeni v miokarda pri produlzhitelno deistvie na niski kontsentratsii serovugleroda.

The authors studied the changes in myocardium during a long-term effect of low carbon sulphide concentrations--50 and 10 mg/m3 by enzyme-histochemical, biochemical and classical histological and electron microscopic methods. THe data from the experiment provided evidence of the involvement of myocardium and vessels in destructive-adaptation reactions in case of carbon-sulphide effect, the destructive processes being with preponderance. They are conditioned both by metabolic disorders of energy-forming systems and the disturbed processes of transport and utilization of energy. Furthermore, the action coordination is disturbed as in the separate muscle cells and the totality of the tissue elements, forming the myocardium as well.

[Changes in the cardiovascular system after continuous and intermittent administration of the rodenticide ratron]. / Promeni v surdechno-sudovata sistema pri monotonno i intermitentno postupvane na ratitsida ratron.

The authors follow up the effect of "Ratron" a raticide (coumarin derivative) with two regimes of administration--monotonous and intermittent--upon the state of the cardiovascular system of experimental animals. The experiment was carried out on 65 female albino rats, grouped into three groups: group I--20 animals treated 5 times weekly with 1/100 LD50 ratron--five weeks; group II--25 animals, administered 5 times weekly every second week 1/50 LD50, and group III--20 controls. At the end of the sixth month, the state of the metabolic processes and the qualitative and quantitative characteristic of the connective tissue of myocardium and aorta were followed up by biochemical and histological methods. Unidirectional deviations in metabolism and the structure of myocardium and aorta were observed under the effect of both regimes, the changes being better manifested with the intermittent administration of ratron. Data were established not only about the general toxic effect of ratron but about the direct lesions of vessels, multiple hemorrhages, interstitial oedema, regeneration of endothelium, structural changes in the small vessels, changes in the components of the basic intercellular substance of the connective tissue.

Liver changes under combined effect of working environmental factors.

Liver changes after separate and combined action of vibration (whole body, 100 Hz, 0.1 mm amplitude) and other factors: noise (white noise 105 dB/A), heat (35 degrees C, humidity 45--55% and air velocity 0.2--0.3 ms-1) and lead (lead acetate, 20 mg/kg) were studied in white rats. The exposure lasted for 2 h daily during 10 days (lead was daily applied per os in a water solution). After the treatment in liver homogenates the activity of SucDH, LDH, and ATP-ase, as well as the quantity of soluble proteins (SP) and -SH gr were determined. In fresh frozen liver slices the activity of SucDH, LDH, and ATP-ase were investigated. Liver samples were studied by light and electro-microscopy. The results show that vibration alone did not produce marked changes, but when the other factors acted simultaneously, more expressed alterations in the liver were found. The most pronounced changes were obtained after vibration and lead effect. The histological, histochemical, and electron-microscopic findings support the biochemical data about certain disturbances in the energy supply and utilization in the liver tissue.

[Effect of changes in the biochemical composition of serum from cows with normal and pathologic puerperiums]. / Vurkhu niakoi promeni v biokhimichniia sustav na kruvniia serum ot kravi s normalen i patologichen puerperium.

Experiments were carried out with 72 cows of the Bulgarian Brown breed kept and fed under equal conditions, giving annually from 2600 to 2800 1 of milk. Groups were formed of animals, showing a normal and a pathologic puerperal period. Blood was sampled at one and the same hour, 7 to 10 days following calving. The levels were studied of vitamins (A, E, and C), total protein, protein fractions, blood sugar, and the bactericidal titer of the blood. It was found that except for vitamin A, which dependably dropped by 20.72% all other factors investigated showed unreliable deviations in cows with acute endometritis as against cows having a normal puerperium. Dependable was also the drop (by 13.93%) of the albumin fraction of the blood in cows with acute endometritis.