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Neonatal administration of hydrocortisone decrease steroidogenesis in the rat adrenals in immature and mature animals production of progesterone and androstenedione reducing, at that. Primary long-term disturbance of central regulatory influences controlling steroidogenesis in adrenals, was proposed. The steroid production disturbance in the gonads was lesser than in the adrenals and was found only in mature rats.

Antisera obtained for certain hormones possessed a high specific effect on homologous hormones. Radioimmunological methods were worked out for determination of these hormones in the blood serum of humans and animals. Clinical use of the above antisera for determination of dehydroepiandrosterone and androstenedione in humans revealed than it could be useful to determine dehydroepiandrosterone in some forms of hypogonadism. Androstenedione is often increased in female hirsutism.

In intact rats, the progesterone level in cytosolic fractions of various organs did not correspond to the level of the progesterone receptors. In ovariectomised animals receiving progesterone, the hormone accumulation in the uterus was fulfilled without participation of progesterone receptors. Over half of the progesterone in the rat uterine tissues exists in receptor-unbound "free" form or, possibly, in the form of complexes with small molecular weight. The uterotropic effect of progesterone in ovariectomised animals seems to be determined by the presence of the hormone in the "free" form in the uterus cells or, possibly, in the form of low-molecular complexes.

Albino mongrel rats were used for the determination of the gamma-glutamyl transferase (gamma-GTF) and acetylcholine esterase (AChE) activities in various brain areas (cerebral hemispheres, cerebellum, hippocampus, brain stem) during acute (1.5; 4 and 6 g/kg i. p.) and chronic (15 months) alcoholic intoxication and alcohol withdrawal (24-48 h, 4 and 8 days). An increase or a decrease in the activity of these two enzymes in the various rat brain areas depends on the dose of ethanol and the time of its action. The activity of gamma-GTF grew in all brain areas during chronic ethanol intoxication; the activity of AChE was also enhanced in three brain areas but it was diminished in cerebral hemispheres. Alcohol withdrawal caused diverse changes in the activities of these two enzymes in various areas of the brain. A tendency to normalization of the gamma-GTF and AChE activities is manifested 4-8 days after alcohol withdrawal.

The activity of gamma-glutamyl transferase (GGTF; EC 2.3.2.2) has been measured in the cerebral hemispheres, cerebellum, hippocamp and brain stem of mature wild and laboratory rodents (Oryctolagus cuniculus, Cavia porcellus, Rattus norvegicus, var. alb., Ochotona pusilla, Mesocricetus auratus, Clethrionimus glareolis, Mus musculus. var. alb.), as well as in homogenates of the whole brain of the tortoise Testudo horsfieldi, frog Rana temporaria and loach Misgurnus fossilis. In wild rodents the activity of GGTF was found to be higher than in laboratory ones. GGTF activity in the brain of warm-blooded animals is higher than that in the brain of the tortoise, frog and loach.

The activity of gamma-glutamyl transferase (GGTF, EC 2.3.2.2) has been investigated in different brain structures (hemispheres, cerebellum, hippocamp, brain stem) of newborn, 3-8-, 15-, 21-30-day and adult rats and piping hare. In both animals, the activity of this enzyme in all the structures investigated increases during ontogenesis. Interspecific differences were found in the increase of the enzymic activity in different brain structures during ontogenesis as well as in the level of the activity in different structures in mature animals.