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A V Osadchuk

Publications and source records attributed to A V Osadchuk.

At least 19 recordsLinked to original sources
PubMed1998

[Genetic control of the activity of microsomal enzymes of steroidogenesis in Leydig cells of inbred strains of mice].

Four activities of key microsomal steroidogenic enzymes (3 beta-hydroxysteroid dehydrogenase-isomerase, microsomal cytochrome P45017 beta, and 17-ketosteroid reductase) were compared in Leydig cells of six inbred strains of mice: A/He, CBA/Lac, C57BL/6J, DD, YT, and PT. The activities of the enzymes were found to vary considerably from one strain to another, depending on the genotype. Analysis of testosterone biosynthesis revealed a decreased activity of 17-ketosteroid reductase as compared to the activities of other microsomal steroidogenic enzymes. The metabolism of pregnenolone and progesterone demonstrated features dependent on the genotype and caused by genotypic differences in the activities of microsomal steroidogenic enzymes. These activities demonstrated a correlative interstrain variation indicative of their coordinated genetic control. The correlative variation may be related to a major gene effect on the activities of microsomal steroidogenic enzymes.

17-Hydroxysteroid Dehydrogenases↗
PubMed1991

The role of the adrenoceptors in the activation of the hypothalamic-pituitary-testicular complex of mice induced by the presence of a female.

A study was made of the role of the adrenergic processes in the activation of the testes endocrine function in male mice of CBA/Lac and A/He strains after their sexual arousal induced by the presence of a sexually receptive female without any tactile contact with a male. The alpha-adrenoceptor blocker phentolamine and the alpha 1-adrenoceptor antagonist prazosin inhibited an increase of testosterone level in the peripheral blood plasma caused by the presence of a female. In contrast, antagonist of the beta-adrenoceptor propranolol and beta 2-adrenoceptor blocker ICI-118.551 significantly intensified the stimulating effect of the female presence on plasma testosterone level. The expression of effects of the adrenoceptor antagonists on the plasma testosterone level depended on a male genotype. At the same time, pretreatment of males with yohimbine, an antagonist of the alpha 2-adrenoceptors, or with metoprolol, a beta 1-adrenoceptor blocker, did not influence the activating effect of a female on the plasma level of testosterone. A conclusion was drawn that during sexual arousal in male mice caused by the presence of a receptive female, the stimulatory effects on the hypothalamic-pituitary-testicular complex were produced through the alpha 1-adrenoceptors, and the inhibitory effects were realized through the beta 2-adrenoceptors.

Adrenergic beta-Antagonists↗
PubMed1990

[The significance of aggressive relationships in a micropopulation in regulating catecholamines in the adrenals of male laboratory mice].

Levels of adrenaline and noradrenaline were changed in the adrenal glands of 6 male mice genotypes during both the period of intense intermale relationships and the period of absence of fights among the males. The character of the catecholamines changes depended on the animal genotype. Significant interlinear correlations were found among the amounts of adrenaline, noradrenaline and dopamine.

Adrenal Glands↗
PubMed1989

[Genetico-neurochemical analysis of the role of brain catecholamines in population hierarchy in male laboratory mice].

Comparative genetic analysis of social dominance in micropopulations of male mice as well as noradrenaline and dopamine levels in brain was carried out. The RT male mice had maximal level of social dominance and the greatest content of brain catecholamines. It is suggested that the capacity for social dominance may depend on the function of the central catecholamine neurons. This suggestion has been confirmed by the data obtained both for interstrain and intrastrain relations between social dominance and catecholamine levels.

Animals↗
PubMed1983

[Genetic endocrine and ethological mechanisms of differential reproduction. I. A comparative genetic analysis of the basal testosterone level in the blood plasma and the relative weight of the testicles and accessory sex glands in male laboratory mice].

Comparative genetic study of the basal plasma testosterone level, relative weights of testicles, seminal vesicles, and preputial glands in 13 strains of laboratory mice showed significant interstrain differences in all indices studied. Under the relative rest condition, a significant positive interstrain (genotypic) correlation was found between basal blood testosterone level and the weight of preputial glands and testicles. At the same time, no intrastrain (paratypic) correlations between hormonal and morphometric indices under study were found. An important positive and highly significant paratypic correlative dependence was seen between the relative weights of seminal vesicles and preputial glands.

Animals↗
PubMed1982

[Effect of the genotype on the serotonin and 5-hydroxyindoleacetic acid content in different sections of the mouse brain].

The levels of serotonin and 5-hydroxyindoleacetic acid contents were estimated in hypothalamus, hyppocampus and midbrain of inbred mice of 12 strains. The levels of serotonin and its metabolite in various parts of brain representing different links of its serotoninergic system were shown to be genetically determined. The correlation analysis revealed that there were two, relatively autonomous genetic systems controlling biosynthesis and catabolism of serotonin in brain.

Animals↗
PubMed1979

[Problems in the genetics of stress. IV. A genetic analysis of the level of autonomic reactivity in emotional stress in rats].

A genetic analysis of hypertensive reactions under condition of emotional stress in three inbred strains of rats (Wistar, Sprague-Dowly and August) and their F1 reciprocal hybrids is carried out. Highly significant genotypic differences in the arterial pressure level during emotional stress and no genetic diversity in the basal state were found. Application of our own methos to genetic analysis of incomplete diallelic tables for Griffing's experimental design 1 (model 1) showed an existence of significant additive component of genetic variance in autonomic reactivity under the stress. The role of the stress as a factor of differentiation of the genetic structure of population is discussed.

Analysis of Variance↗
PubMed1978

[Genetic and physiological mechanisms of the hypertensive reaction in emotional stress in rats].

The experiments were performed on rats of three inbred strains (Wistar, August, and Spreg-Dowley). Arterial pressure was measured during acute emotional stress. The reactivity of arteries to vasopressor stimuli, the corticosteroid function, and the humoral pressor activity of plasma were also studied to investigate some physiologic mechanisms of genetically determined differences in the level of arterial pressure during stress. It was established that the rat strains which were examined did not differ in the level of arterial pressure at rest, but showed marked differences in pressure under conditions of stress: the greatest rise in pressure was noted among August rats, the least among Wistar rats, while animals of the Spreg-Dowley strain occupied an intermediate position. It is concluded that inter-strain differences in the pressor reaction reflect genetical peculiarities in the system of nonspecific stress reactivity of animals.

Acoustic Stimulation↗
PubMedDate not supplied

Involvement of the catecholamine mechanisms in the activation of mouse hypophyseotesticular complex induced by the female presence effect.

We have studied the role of the adrenergic and dopaminergic mechanisms in the activation of the endocrine testicular function of CBA/Lac and A/He male mice induced by the presence of a female in estrus without any tactile contact with a male. The alpha-adrenoreceptor blocker phentolamine inhibited an increase in the peripheral blood plasma testosterone level caused by the receptive female challenge. Propranolol blockade of beta-adrenoreceptors abruptly increased the stimulating effect of the receptive female presence on the blood testosterone level. The expression of the adrenoblocker action on the blood male sex hormone level depended on a male genotype. The dopamine receptor blocker pimozide produced a moderate effect on the blood testosterone but an attempt to separate its influence into the male sex hormone tonic secretion and the blood testosterone level against a background of sexual activation failed. It was concluded that the adrenergic mechanisms were involved in the activation of the hypothalamo-hypophyseotesticular complex induced by the presence of the receptive female.

Animals↗