[The influence of a single glucocorticoid administration on the DNA and the nitrogen-content as well as on the beta-glucuronidase activity of rat skin during postnatal development (author's transl)].

In the paper presented here the following parameters on the skin of pure-bred Wistar inbred rats were investigated during the early postnatal maturation period: DNA-content (according to Burton 1956), nitrogen-content (according to Strauch 1965), beta-glucuronidase activity (according to Fishman 1974), partly also protein-content (according to Lowry 1951). At the same time, we tested if a single i.p. injection of 6-methyl-prednisolone, applied exactly at the same time of the day 24 h preceding the killing, has an influence on the above mentioned quantities in comparison to the control group (possibly dosage-dependent). In the observation period (2nd, 4th, 6th, 9th, and 14th day) a linear, statistically significant increase of the nitrogen-content could be stated on the skin. After an initial increase up to the 4th day of life the DNA-content significantly decreases during the following postnatal maturation period until the 14th day. These results could be obtained both in the control groups, and in the animals treated with different dosages of 6-methyl-prednisolone. It is of importance that these parameters (especially the cell and the DNA-content respectively) were not statistically significantly changed by pretreatment with the glucocorticoid at any day investigated. The total activity of the further tested lysosomal indicator-enzyme beta-glucuronidase increases during the postnatal maturation period up to its maximum on the 9th day of life before it decreases till the 14th day. The applied dosages of the glucucorticoid led to a general increase of the enzyme activity, which, however, was only exceptionally statistically significant. This enzyme induction could also by discussed in terms of a maturation acceleration. Dosage-dependent differences could partly be demonstrated.