RESUMO
Quantitative biochemical analyses of the beta-glucuronidase total activity and the total DNA-content carried out on selected parenchymal and mesenchymal organs of 455 Wistar inbred rats (strain Chbb:THOM (SPF) from 56 litters (untreated or treated with 1 mg betamethasone/kg b.w. s.c. on both the 18th and 19th days of pregnancy, applied to the mother animal) led to the following results: The DNA-content of lung, liver, kidney, skin and rib cartilage declined continuously both in the controls and in the treated group during the postnatal observation period (from the 1st to the 15th day p.p.). The prenatal glucocorticoid administration led to a decline in the DNA-content in comparison to the untreated controls, especially evident in the first postnatal days. The beta-glucuronidase activity of lung, liver and kidney showed an increase in the postnatal development phase to a maximum occurring organ-dependently on different days with a decrease afterwards. Due to glucocorticoid-pretreatment of the mother animals the newborn rats showed significantly higher enzyme values within the first postnatal days than did the untreated controls. Between the 6th and 9th day (depending on the organ) the same beta-glucuronidase activities could be found on pretreated and untreated animals. For the further ages tested in this study (till the 15th day of postnatal development) the enzyme activity of the experimentally treated litters was lower than that of the untreated controls. In connection with related findings, especially regarding morphological changes in the lung, the induction of beta-glucuronidase as well as the decrease in the DNA-content due to prenatal glucocorticoid pretreatment are discussed in terms of a maturation acceleration.
