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Biomedical subjects

V B Popov

Publications and source records attributed to V B Popov.

12 recordsLinked to original sources
PubMed1983

[Decrease in the ascorbic acid content of guinea pig tissues caused by thalidomide].

It has been demonstrated that thalidomide is capable of a noticeable stabilization of the enzymes from rabbit, pig and guinea-pig liver microsomal fractions. Administration of thalidomide to guinea-pigs resulted in an increase of microsomal hydroxylase activity measured by the aniline test. The growth of the activity of microsomal enzymes led to an abrupt drop of ascorbic acid concentration in guinea-pig organs. It is suggested that thalidomide has a teratogenic action on the species which are incapable of the synthesis of ascorbic acid by making this vitamin deficiency in embryonal tissues. Probably, it is the deficiency of ascorbic acid that inhibits the synthesis of collagen in embryonal limbs and disturbs their sensory ganglia.

Adrenal Glands↗
PubMed1981

[Comparison of the effectiveness of various methods of testing drugs for embryotoxicity].

A comparative investigation on efficiency of four modern methods for testing embryotoxicity (intraamniotic administration, cultivation of postimplanted rat embryos in medium when certain teratogens were administered by various methods, test techniques on pregnant animals, testing, by CHEST--chick embryo toxicity screening test--method on chick embryos) was performed with a well known teratogen -- cyclophosphamide. A satisfactory correlation between the results was obtained, but a greater efficiency, less time for obtaining final results and greater sensitivity was noted for the new test methods in comparison to routine testing on pregnant animals. Advantages and disadvantages of every method applied were discussed.

Amnion↗
PubMed1981

[In vitro development of the postimplantation embryos of laboratory rodents in human blood serum].

Rat and mouse embryos at the stage of the first somites formation (1-5 pairs) cultivated in human blood serum demonstrated its embryolethal and teratogenic effect. The embryos taken at a later stage (11-18 pairs of somites) developed normally and could be compared with the development of the rat embryos in homologous blood serum. There was no difference in the development when the embryos were cultivated either in male or female blood serum. The stage of embryogenesis 11-18 pairs of somites is recommended for in vitro experimental revealing in the human serum of embryotoxic factors induced by certain external influences.

Animals↗
PubMed1981

[Action of cyclophosphamide in a culture of rat postimplantation embryos].

The effect of cyclophosphamide (CPA) on the development of postimplantation rat embryos in vitro both in the homologous blood serum added with CPA and in the blood serum of the animals pretreated with CPA was studied. The latter method, unlike the former one, allows to take into account the metabolism of CPA in the organism of rats. It is proved by the similarity of teratogenic effects upon cultivation of the embryos in the blood serum of the rats pretreated with CPA and upon the effect of CPA on the embryos developing in vivo. The method for cultivation of the postimplantation embryos in vitro may be recommended for testing drugs subject to metabolic transformations.

Animals↗
PubMed1981

[Embryotoxic effect of cyclophosphamide after being biotransformed in a culture of postimplantation rat embryos].

Biotransformation of cyclophosphamide to teratogenous products in the presence of the rat hepatic microsomal fractions and NADP.H2 was carried out in the medium for cultivation of postimplantational rat embryos. Nontoxic concentrations of all components participating in the reaction and threshold concentrations of cyclophosphamide were defined. The results obtained were compared with the data of the drug action on the embryos of the same age developing in the maternal body. The developmental anomalies appeared to be similar in both cases. The method for detecting the teratogenous products of cyclophosphamide bioactivation in the culture has been demonstrated to be highly sensitive as compared with the standard biological tests.

Abnormalities, Drug-Induced↗
PubMed1981

[Embryotoxic effect of ethanol and its biotransformation products in cultures of postimplantation rat embryos].

A study was made of the effect of ethanol (6.5-108 mM) and its immediate metabolite, acetaldehyde (4.5 microM-45 mM) on 9.5-day-old rat embryos cultivated in vitro. Biotransformation of the nontoxic concentration of ethanol (17 mM) to teratogenic products was made by addition to the culture medium of a soluble fraction of the rat liver (0.2-0.55 mg protein/ml), NAD (0.25 mM) and sodium pyruvate (2.3 mM). Malformations obtained after biotransformation of ethanol were similar to those obtained after direct action of acetaldehyde. The roles of acetaldehyde and ethanol in the etiology of fetal alcoholic injury are discussed.

Acetaldehyde↗
PubMed1980

[In vitro cultivation of mouse embryos during the initial stages of organogenesis].

Optimal conditions for in vitro cultivation of mouse embryos were sought. The embryos at 8--9.5 days of development were explanted into the culture in rotating tubes. A number of nutritional media were studied: the human umbilical blood serum; the rat blood serum, as well as its mixture (1 : 1) with Eagle's medium. It was demonstrated that the optimal medium for cultivation of 8-day-old embryos was the mixture of the rat blood serum with Eagle's medium, and for 8.5--9.5-day-old embryos--the rat blood serum, as well. Comparing in vitro and in vivo embryonic development, it was evident that in the cultivated embryos the parameters characterizing their growth decreased significantly. Possible causes of this phenomenon are discussed.

Animals↗
PubMed1977

[Comparison of the effect of chloridin on rat embryos during postimplantation periods of development in vivo and in vitro].

The effect of chloridin (2,4-diamino-5-parachlorophenyl-6-ethylpyrimidine) on the rat embryos developing in the maternal organism and on the embryos explanted 24 hrs after the treatment in the nutrient medium (homologous blood serum) was compared. The pathological processes both in vivo and in vitro were shown to be similar. The number of atypical and died embryos in vitro was, however, much higher, apparently due to the absence of some protective membranes in the cultivated embryos.

Abnormalities, Drug-Induced↗
PubMed1976

[Cultivation of mammalian postimplantation embryos outside the body].

The possibility is considered to use in vitro cultivation of the embryos of laboratory rodents at the postimplantation developmental stages in experimental embryology and teratology. Different variants of the method are estimated and the optimal conditions of cultivation are described (nutrient medium, gaseous phase, depth of explants' immersion, rate of medium flow, etc). The causes are discussed which limit the duration of in vitro development and enhance the appearance of some defects. The results are given for application of the method when studying the mechanisms of teratogenic effect of chemical drugs.

Abnormalities, Drug-Induced↗
PubMed1976

[The development of yolk circulation in normal rat embryos].

To reveal the developing vessels of the yolk placenta the erythrocytes were stained with benzidine. The development of vessels was studied in vivo and in transplantation of embryos in the homologous blood serum. The pattern of branching of blood vessels in the yolk sac of 12-day embryos was established. The development of the blood circulatory system started on the 9,5 day (the anlage of sanguineous islands), the definitive state was acquired by the 12th day. The development of vessels in vitro after removal of the parietal layer of the placenta is dependent on the mophological stage at the moment of transplantation. In explantation of embryos with 2--3 pairs of somites which are being already formed, the yolk vessels develop as those in control. In transplantation of presomite embryos the development of vessels is sharply disturbed, in transplantation of embryos of the egg cylinder stage the vessels are not developed. The inducing role of the yolk placenta perietal layer in the development of blood vessels in the vascular layer is supposed.

Animals↗
PubMedDate not supplied

[Time periods for the realization of the embryotoxic action of cyclophosphamide and chloridin in vivo and in vitro].

Female rats with 10-day pregnancy were given cyclophosphamide (30 mg/kg) or chloridin (25 mg/kg). Following 15 minutes - 24 hours the embryos were explanted into the cultural medium containing no teratogenic agents indicated. It has been shown that pathological processes in the embryos became irreversible 15 - 30 minutes after the mother was exposed to cyclophosphamide and 6 hours after chloridin exposure. In the other experiments, embryos from intact females were incubated (1 - 4 hours) in the blood serum of rats given the same drug doses and transferred to the serum from intact animals. The times of cyclophosphamide action realization remained unchanged, while those of chloridin decreased to 1 hour.

Animals↗