[Effect of cold exposure in the early postnatal period on the hormone content and tyrosine aminotransferase activity in adult rats].

The cooling of new born rats within the first 7 days of life (15 min, +2--+4 degrees) was shown to lead to stable hormonal changes in their adult state (4 to 5 months): the content of corticosterone and insulin in blood increased twice. The short cooling of adult rats resulted in the increase of trioiodothyronine content and decrease of insulin content in blood and the increased induction of tyrosine aminotransferase in the liver. The data obtained corroborate an idea that the induction of certain biochemical processes during early postnatal period, due to the involvement in the transcription of certain genes, leads to stable changes in the spectrum of metabolic processes and reactions.