A peptide agonist of the neural cell adhesion molecule (NCAM), C3, protects against developmental defects induced by a teratogen pyrimethamine.

The neural cell adhesion molecule, NCAM, not only plays an important role in neuronal migration, differentiation and formation of connections in the developing nervous system, but also in the condensation of the mesodermal mesenchyme of the limb bud. Therefore, NCAM may be regarded as a target molecule for preventive strategies aimed at minimizing the effects of teratogens affecting the prenatal development of the nervous system and the skeleton. Treatment of fetuses with the teratogen pyrimethamine results in a reduced body weight, microcephaly and malformations of the hind limbs and forelimbs, e.

[The role of the yolk sac in copper metabolism during rat embryogenesis].

Using the immunoblotting method, the synthesis of two copper-transporting P1-type ATPases, ATP7A (a candidate for the product of the Menkes disease gene) and ATP7B (presumed product of the Wilson disease gene), in the yolk sac cells of rat embryos at days 11 and 20 of embryogenesis was demonstrated. Concomitantly, yolk sac cells produce ceruloplasmin, a soluble copper-transporting glycoprotein, a proportion of which in secreted proteins progressively diminishes, attaining 5.2% at day 11 and 3.

[The embryo-protective action of antifein derivatives in chloridin-induced teratogenesis].

We studied the effect of propyl- and ethylnorantifein on chloridine-induced abnormalities of extremities in rat embryos. Chloridine (50 and 25 mg/kg, given through the gastric tube) was administered to rats on day 14 of pregnancy, and its embryotoxic effect was estimated from the state of fetuses and implantation sites on day 20 of prenatal development. Propylnorantifein had fetoprotective properties both after intraperitoneal (10 mg/kg) and after intraamniotic (6 and 0.

[A comparative study of the transport dynamics of the peptide moiety of the milk ceruloplasmin molecule in the body of rats with embryonic and adult types of copper metabolism].

In chase experiments, we followed the distribution of [125I]-ceruloplasmin prepared from human breast milk orally administered to young rats. Experiments were conducted using six-day-old rat pups (the embryonic type of copper metabolism) or 35-day-old ones (the adult type of copper metabolism). Using the technique of rocket immunoelectrophoresis, we have demonstrated that in six-day-old rats [125I]-ceruloplasmin was transferred from the gastrointestinal tract to the bloodstream and could be detected there over a period of 4 h.

Population profile of brain asymmetry in rats after intra-amniotic administration of vasopressin.

The effects of intra-amniotic administration of 1-desamino-8-D-arginine-vasopressin (DDAVP) at 14 days of embryogenesis on movement asymmetry in neonatal and mature mongrel white rats were studied. Controls consisted of intact and sham-operated animals, as well as rats given intra-amniotic saline. The population profile of asymmetry was assessed in terms of the tail position of rats aged two days, and also in terms of the direction of excursions in a T-maze in three-months males.

[The effect of benzine and formaldehyde on the prenatal development of rats with induced iron trace-element disorder].

Iron-deficiency anemia induced in the maternal organism markedly enhances embryotoxic and teratogenic effects of the studied pollutants: gasoline and formaldehyde. The prenatal effects of these drugs against the background of iron-deficiency state in pregnant females leads to development of the main feature of the tissue hypoxia, decompensated metabolic acidosis, in both the maternal organism and 20-day embryos.

[Population profile of brain asymmetry in rats after intra-amniotic administration of vasopressin].

Vasopressin administration induced a right-sided bias in the rat litter, the asymmetry being similar to a right-sided bias in the turning behaviour of adult male rats in the T-maze. The findings suggest the nigrostriatal system to be responsible for the lateralising effect of vasopressin in the brain.

Embryotoxicity of silver ions is diminished by ceruloplasmin--further evidence for its role in the transport of copper.

The effect of alimentary administration of silver salts upon embryogenesis in rats was studied. Feeding of female rats throughout the term on a regular diet supplemented with AgCl did not cause alterations of their physiological functions, despite the fact that enzymatically active copper-containing ceruloplasmin (CP) was eliminated from the blood plasma. However, developmental abnormalities of embryos, their prenatal death or the 100% mortality of the newborns in the first 24 h of life was seen.

[The toxic effect of serotonin in direct and mediated actions on rat embryos].

Embryotoxic effect of serotonin in direct (intra-amniotic administration) and indirect (subcutaneous administration) treatment was studied. In both cases serotonin causes embryo death and different abnormalities in development in small number of embryos. Mechanism of serotonin embryotoxic effect is under discussion.

[The role of the maternal genotype in the realization of the embryotoxic activity of teratogens].

Against the background of the induced iron deficit ethanol (6.4 g/kg) causes aggravation of the embryolethal effect and anomalies in 15% of embryos in 14-day pregnant rats. Changes in the genome of rat males and females after the injection of the plasmid with a foreign gene at the stage of two pronuclei and the subsequent crossing with intact animals account for the increase in sensitivity of embryos to subteratogenic doses of sodium salicilate.

[Influence of ceruloplasmin on the embryotoxic effect of silver ions].

The effect of alimentary administration of silver salts upon embryogenesis in rats has been studied. Feeding of AgCl to pregnant female rats throughout gestation did not result in any alterations in their physiological functions, although the active copper-containing ceruloplasmin (Cp) was eliminated from the blood stream. However, anomalous development of embryos, their prenatal death or total mortality of newborn rats within the first 24 hours after birth were evidenced.

[A comparison of the characteristics of chromosome nondisjunction in the first maturation division of mouse oocytes heterozygous for balanced structural rearrangements of the chromosomes].

Peculiarities of non-disjunction of chromosomes in the first meiosis of maturation of oocytes in mice heterozygous in the Robertsonian and nonuniform reciprocal translocations have been determined. Mice, heterozygous in one Robertson's translocation, had general frequency of chromosomal non-disjunction in the 1st meiosis of oocyte maturation equal to 17%; by two Robertsonian translocations the total frequency of genetically deficient oocytes amounted to about 77%, in case of unequal reciprocal translocation--to 50%. In two latter cases genetic disturbances were due to unbalanced euploid chromosome sets.

[Biosynthesis and secretion of ceruloplasmin by rat mammary cells during lactation].

Some peculiarities of rat milk ceruloplasmin (CP) biosynthesis have been analysed. Electrophoretic and immunoelectrophoretic data suggest that rat milk contains up to 20 mg/100 ml of CP. Rat milk CP is represented by a single molecular form whose molecular mass, enzymatic activity and antigenic properties are fully identical with those of serumal CP.

[The embryotoxic effect in rats exposed to the blood serum of newborn infants tested for the presence of transfer factors].

Pregnant rats (day 14 of gestation) received intraamniotic injections of newborn human serum. Transfer factors (TF) present in injected serum produced significant embryotoxic and teratogenic effects, as well as changes in coordination of motor activity (EMG) in newborn rats. The extent of embryological disturbances and the motor activity of 33- to 34-day old recipient rats depend on TF concentration (at serum dilution 1:2) and on the state of infant's motor functions ("normal" group and "risk" group).

[The mechanisms of the teratogenic action of alcohol].

Under study was the influence of different doses and methods of administration of ethanol on embryogenesis of rats and the effect of some shifts in homeostasis of a female rat on a manifestation of teratogenic effect of ethanol. Embryogenesis of rats is resistant to action of ethanol and acetaldehyde. Shift in the acid-base balance to the acid side is not thought to be determining in the mechanism of the appearance of the fetal alcohol syndrome, while the embryotoxic effect of ethanol manifests itself against the background of an iron-deficient state of the maternal organism.

[The stage-specific sensitivity of rat embryogenesis to ethanol administered intra-amniotically and by other methods].

The exposure of rat fetuses to ethanol by direct intra-amniotic injection in the afternoon of the 14th day of embryogenesis resulted in developmental anomalies (34%), the defects located mostly in the left extremities. Intraperitoneal injections of ethanol at the same period of pregnancy resulted in analogous injuries but only in occasional fetuses. There was no embryotoxic effect after exposure to high doses of ethanol by per os.

[The prevention of congenital developmental anomalies in rats].

Preventive administration of Eleutherococcus XXX extract during prenatal and pre-embryonic periods of development prevents embryotoxic effect of subsequent treatment of pregnant rats with ethanol and sodium salicylate. Eleutherococcus abolishes embryotoxic and teratogenic effects of ethanol manifested against the background of experimental syndrome of iron deficit in pregnant females. Mechanism of its antiteratogenic action is probably based on stimulation of cell detoxification mechanisms, increase in energy potential of cells, as well as on stabilization of structural and functional state of cell membranes.

[The effect of amniotic fluid taken from women in labor on the morphofunctional development of fetal and newborn rats].

Amniotic fluid from women was injected intra-amniotically to rats at the 14th day of pregnancy in a dose 0.3 ml. Morphological and functional parameters of embryonic development of rats and EMG activity of rat puppies at the age of 30-34 days differed from control ones with respect to the degree of maturity and motor disturbances of newborn babies.

[Astrocyte death in organotypic cultures of fetal spinal cord from rats with unilateral micromelia].

Growth and differentiation of neurons and glia in spinal cord explants of 16 days old rat fetuses with teratogen-induced left-sided micromelia were studied. Progressive destruction of astrocytes that differentiate in interstitial zone of cultures was observed in 37% of explants of the left side, while the development was normal in cultures of the right side. Possible mechanisms leading to destruction of astrocytes in cultures of spinal cord regions that innervate anomalous limbs are discussed.

[The transformation of the mammalian genome and the teratogenic activity of chloridin].

Susceptibility to the effect of teratogen chloridine of three generations produced from transgenic rats with human growth hormone gene was investigated. The offsprings were shown to reveal elevated teratogenic injury as compared with intact animals.

[Alcohol-drug interaction in rat embryogenesis: the effect of separate and combined action of sodium salicylate and ethanol].

A combined administration of sodium salicylate and ethanol to female rats in threshold embryotoxic doses on the 9th, 10th, 12th and 13th days of pregnancy results in a sharp increase of embryolethal and teratogenic effects. The embryotoxic effect of sodium salicylate and ethanol at their combined injection exceeds the summational embryotoxic effect at the separate action of the preparations. The spectrum of malformations after their combined effect does not differ from that induced with sodium salicylate.