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A study is presented of the placenta histogenesis and development of cardiotoxic effect in rat progeny under the effect of the synthetic pyrethroid decis. The drug was introduced to pregnant animals perorally in 1/20 and 1/100 LD50 doses during the critical periods of neonatal development. Morphological disorders were revealed as well as a reduction of enzymatic activity (OP, SDG) in the placenta and ultrastructural and histochemical disorders of these enzymes in the myocardium of the progeny at different periods of ontogenesis. The revealed changes evidence the capacity of the pyrethroid decis to penetrate through the placental barrier and produce a cardiolesioning effect on the progeny.

It has been established that administration of aphos to chickens within a wide dose range (3000-25 mg/kg) produces a retarded neurotoxic action that is manifested by the development of ataxia, pareses and paralyses; delay in the rate of the distribution of excitation via the peripheral axons, disorders of myoneural lability; degeneration of myelin fibers, focal granular degradation of myelin. The retarded neurotoxic action is not caused by impurities contained by the technical-grade preparation in view of the fact that such an action is also common to the chemically pure aphos.

Cholinestarase activity in the cardiac neural elements of pregnant animals and in their offspring was studied under the effect of chlororganic pesticide -- polychlorcamphen and phosphororganic pesticide -- valexone. The substances in question were demonstrated to produce variously pronounced unidirected changes in cholinesterase activity in neural structures that testifies to interconnection and dependence of the changes in the system mother -- fetus. The alterations observed in nonsynaptic (trophic) cholinesterase make it possible to speak about the disorder of cholinergic innervation and about the importance of acetilcholinesterase trophic function as a regulator of cellular processes, an inhibitory index of differentiation during embryogenesis.

Daily peroral administration of chlororganic pesticide hexachlorobutadiene in doses 8.1 mg/kg (1/20 LD50) to pregnant rats results in certain ultrastructural changes of neurocytes and myelin fibers of the spinal cord both in the animals and their offspring (newborns and 1-2-month-old rats). By means of electron paramagnetic resonance (EPR) method, changes in intensity of the EPR-signals of free radicals in the spinal cord, ceruloplasmin of blood serum have been revealed in the experimental pregnant animals, as well as in 1-month-old rats (in the latter--in the brain, too). Gas-liquid chromatography reveals the preparation contents in the adrenals, heart, brain and spinal cord, in the uterus of the pregnant animals, as well as in corresponding organs of their offspring. Certain retardation in growth and decrease in body mass are noted in the offspring.

When pregnant rats are administered chlororganic pesticide dilor, certain ultrastructural changes are observed in neurocytes and in myelin fibers, in the spinal cord, that demonstrates some disorders in cellular and tissue metabolism. In the newborn spinal cords a retarded differentiation is observed against the background of an intense cellular metabolism. By means of the electron paramagnetic resonance technique, an increasing concentration of free radicals in the brains and spinal cords of the pregnant animals and in their one-month-old offsprings is demonstrated. The investigation on fatty acid composition of lipids in pregnant test animals demonstrates a decrease in cholysterine, steroids and some fatty acids in myelin fractions and in synaptosomic membranes.

Experiments conducted on pregnant albino rats showed that in daily oral administration of polychlorokamphene--a chlorine organic compound widely used in agriculature--in a dose of 12 mg/kg (1/20 LD50) there was interrelation between the structural and the enzymatic changes in the nerve elements of the organs under study. They consisted in the focality of the affection of the nervous structures of the brain cortex, and in increase in the destructive processes involving the nervous structures of the heart, uterus, spinal cord at the end of pregnancy. A peculiar enzymatic reconstruction with the preservation of the activity of the cholinesterase (CE)-positive pericellular structures (whose number was markedly decreased in comparison with control) was noted against the background of reduction of the CE activity. The prevalence of destructive processes by the end of pregnancy was conditioned by a considerable accumulation of the preparation in the heart, uterus, and the brain (as shown by thin-layer chromatography). The presence of polychlorkamphene in the organs of fetuses pointed to disturbances in the permeability of the transplacental barrier and to a possible influence of the preparation on the development of the fetal nervous system.