[The effect of a low dose of ionizing radiation on the activity of cAMP-dependent phosphodiesterase and protein kinase of chicken thymus in ontogenesis].

Dynamics of changes in activities of cAMP-dependent enzymes, phosphodiesterase and protein kinase, were studied in the thymus of intact and irradiated, prior to incubation, (0.05 Gy) chicken embryos and chicks. The changes observed were wave-like.

[Electron immunocytochemistry of lymphocyte surface immunoglobulins in the bursa of Fabricius in the pre- and early postnatal ontogeny of chickens].

The appearance and localization of surface immunoglobulins on B-lymphocytes of the bursa of Fabricius of developing chick embryos and chicks were studied by immuno-electron-cytochemical peroxidase-antiperoxidase (PAP) method. Ultrastructural characteristics of marked and unmarked lymphocytes of the bursa of Fabricius was shown. The increase in the density of reaction product on PAP-complex in the course of lymphocytes differentiation was established.

[Cyclic nucleotides in the ontogeny of the chick thymus].

The dynamics of cAMP and cGMP content of the thymus homogenate from developing chick embryos and chickens was studied during ante- and postnatal development. Changes in the content of cyclic nucleotides bear an oscillatory pattern. At the early stages of embryogenesis (9 to 11 days of incubation) the content of cyclic nucleotides was low and gradually increased by 13 days of incubation.

[Effect of preincubation irradiation on adenylate cyclase activity and cyclic nucleotide content of the thymus in chick ontogenesis].

Adenylate cyclase activity and cAMP and cGMP content of thymus have been studied in intact and irradiated (0.029 Gy, prior to incubation) embryos and chickens. The enzyme activity is stimulated during the postnatal development.

[The effect of small doses of ionizing radiation on the cAMP system in the thyroid gland of chick embryos].

Adenylate cyclase activity and cyclic adenosine monophosphate (cAMP) content were studied in the thyroid gland of intact and irradiated (0.029 Gy given before incubation) embryos and chickens. The enzyme activity was stimulated and the nucleotide content increased on the 18th day of the embryo development.