Changes in the heart of neonatal rats after cryptosporidial gastroenteritis of different degrees of severity

Disturbances at the childhood age increase risk of appearance of cardiovascular disease decades later. The nature of this interconnection called ontogenetic programming is not completely understood. Valuable source of knowledge about mechanisms of ontogenetic programming are data of interspecies study of biology of the body life cycles understanding on the triggers and mechanisms are the cross-species comparative data on life-cycle and heart aerobic capacity. Taken into account the interspecies differences, these data allow finding the correct direction of experimental investigations. Results of studies of almost 100 homoiothermal species have shown the slow growth and a high loading on the heart at postnatal development to decrease its aerobic capacity in adults. Basing on these data, we suggested that the neonatal infectious gastroenteritis causing tachyarrhythmia, malabsorption, and the growth deceleration might lead to pathologic changes in the heart. Our task was to evaluate the effect of cryptosporidial gastroenteritis of different degrees of severity on heart of neonatal rats. By using methods of Real-Time PCR, immunocytochemistry, image analysis, and study of atrial septum (ostuim primum), we have established that a gradual increase of intensity of infestation with Cryptosoridium parvum oocysts causes sharp changes corresponding to “all-or-nothing” response. At a weak infestation the atrial septum was close (like in control), while significant changes in expression of isoforms of heavy chains of α- and β- myosin were absent. At the intermediate and severe infestation, in the atrial septum the foramen ovale was visualized and there were observed the cardiac atrophy and a strong shift of ration of expression of myosin heavy chains toward the low-velocity of β-chain. Thus, by disturbing the frequency-strength ratios and causing the outflow of resources from the formed heart, the neonatal cryptosporidiosis produces pathological changes of the organ molecular and anatomical structure. Our results can be interest to evolutionary biologists and physicians, as they show the importance of knowledge of evolutionary-comparative investigations for search for novel risk factors of heart diseases and demonstrate interconnection between gastroenteritis, pathology of atrial septum, and a change of composition of the main contractile proteins in cardiomyocytes.     

Effect of catamine AB on the generative function and chromosome apparatus of the bone marrow cells in white rats

In a chronic experiment (6 months) performed on non-inbred white rats effect of cationic superficially active substance catamin AB on the structure and function of male and female gonads, state of the offspring and on the chromosome apparatus of the bone marrow cells has been studied. The preparation is intragastrically injected in doses 10, 1, 0.1 mg/kg. Catamin AB in the dose of 10 mg/kg produces an essential decrease in the specific mass of the testes, reduce in the spermatogenic index, increase in the canaliculi number with exfoliated epithelium, lowered mobility and diminished amount of alive spermatozoa. In the ovary amount of mature follicles becomes less and the number of atresic corpuscles and atresing follicles rises; plethora of the medullary substance occurs in the organ with signs of stasis in the venous bed. In the dose 1 mg/kg catamin AB results in less pronounced changes in the testes and does not produce any pathological disturbances in the ovaries. The preparation does not influence on mating in the test animals, but in the dose 10 mg/kg results in a decreasing fertility because of pre- and postimplantational death of embryos. The changes mentioned are connected with a total toxical effect of the preparation. Catamin AB does not possess any mutagenic effect in the doses tested.     

Acute cytogenetic effects of potassium bromate on rat bone marrow cells in vivo

The acute cytogenetic effects of potassium bromate (KBrO3) on rat bone marrow cells in vivo were studied. The incidence of chromosome aberrations in bone marrow cells increased rapidly, reaching a maximum level 12 h after intraperitoneal injection and decreased within 24 h. Dose-response relationships were obtained for both intraperitoneal and oral administrations.     

The cytopathic and cytogenetic sequelae of chronic inhalational exposure to formaldehyde on female germ cells and bone marrow cells in rats

A study was made of cytopathological and cytogenetic effects of formaldehyde chronic inhalation, in doses 0.5 and 1.5 mg/m3, on the female rat's germ and marrow cells. The harmful effect of formaldehyde on germ cells (according to the patterns of early embryogenesis) is noted under the dose 1.5 mg/m3 only, while the reliable clastogenic and cytogenetic effects on the marrow cells were revealed even in the dose 0.5 mg/m3. It is concluded that the differences between effects of small doses of formaldehyde on different cell systems were evidently caused by the specific cell dynamics of these systems.     

Acute and subacute cytogenetic effects of the trihalomethanes on rat bone marrow cells in vivo

The mutagenic effects of the trihalomethanes (THMs: chloroform, CHCl3; dichlorobromomethane, CHCl2Br; dibromochloromethane, CHClBr2; bromoform, CHBr3), found in chlorinated drinking water have been studied for their ability to induce chromosome aberrations (CA) in vivo in rat bone marrow cells. THMs were administered intraperitoneally (i.p. acute) and orally (subacute). Using a maximal dose of 1 mmole/kg body weight, positive results were noted for CHCl3, CHCl2Br, CHClBr2 and CHBr3 with i.p. treatment, and for CHCl3 and CHBr3 with oral treatment. The time-dependent increase in CA showed a maximum level at 12 h after i.p. injection and at 18 h after the fifth and last day of oral treatment.     

Mitotic indices of bone marrow cells and their correlative relationships in dogs]

It was shown that mitotic indices of erythroblasts, basophilic and polychromatophilic normoblasts, myeloblasts, promyelocytes and myelocytes decline depending on the degree of cell differentiation and are quantitatively expressed by the ratio 4:2:1. The feedback between the value of mitotic indices and the number of cells which is expressed by power dependence was identified.     

Liproprotein inhibitor of bone marrow cells in tumor-bearing rats.

The role of a plasma inhibitor of erythropoiesis is evaluated in rats with Walker-256 carcinoma (W-256). Plasma from tumor-bearing rats was treated by gel filtration chromatography (Sephadex G-150) and fractions were combined into four pools on the basis of mol. wt. Inhibitory activity was assayed by adding an aliquot of the plasma fractions to normal rat marrow cells which were cultured for 24 hr with and without erythropoietin. 59Fe-heme synthesis, [3H]thymidine DNA synthesis, and 14C-leucine protein synthesis were studied. The results indicated that cultures containing the high mol. wt. pool (greater than 400,000 daltons) had significantly decreased heme, DNA and protein synthesis. This inhibitor also diminished the response to erythropoietin in polycythemic mice. The lower mol. wt. pool stimulated heme synthesis in vitro. To identify the inhibitor further, plasma lipoprotein classes were isolated by density gradient ultracentrifugation. The very low density lipoprotein (VLDL) and chylomicron fractions markedly inhibited DNA, protein and heme synthesis. Low density and high density lipoprotein fractions were inactive. A lipoprotein inhibitor of erythropoiesis was also identified in cancerous ascitic fluid, and to a lesser degree, in normal rat plasma. We suggest that this VLDL inhibitor of marrow erythropoiesis is a contributing factor in the anaemia of cancer.     

Effects of aluminum on erythroidal cells in bone marrow in rats

The study has been carried out on Wistar rats. The aim of the present study was to trace the effect of aluminum on erythroidal cells in bone marrow in rats. The number of proerythroblast after 10 days of experiment with aluminum slowly decreased up to 80 days of experiments. However, the number of basophilic erythroblasts after 10 days insignificantly increased but after 20 days gradually decreased up to 80 days of experiments. The bone marrow polichromatic erythroblasts after 10 days of experiment slightly decreased, however after 20, 40 and 80 days of experiments the values decreased significantly. The quality of orthochromatic erythroblasts after 10 days of experiments dropped and after 20, 40 and 80 days of experiments significantly decreased compared to the control value. Aluminum also brings about histological changes in the bone marrow. The statistical significant reductions of hemoglobin and hematocrit levels were found in the aluminum exposed rats.     

Cytogenetic changes in the bone marrow cells of long-term irradiated rats]

The occurrence and characteristics of the chromosome structural changes in femur bone marrow cells under continuous irradiation with the exposure rate of 50 R/day within 90 days was followed. The 25% increase in the chromosome aberration frequency was observed within 7 days of the irradiation, and then the aberration rate was constant up to the end of the irradiation (90 days).