ABSTRACT
A joint study was undertaken in the laboratories of five pharmaceutical companies to evaluate accumulated data on the progeny of mice, rats and rabbits of various strains or breeds. The recorded morphological deviations from normal were classified according to the time of their occurrence during embryonic and foetal development, and three categories were differentiated. Comparison of the data from the various laboratories in general revealed similar results, and the variations observed are presumed to be due to differences in experimental conditions.
Subject(s)
Teratogens/pharmacology , Animals , Body Weight/drug effects , Congenital Abnormalities/epidemiology , Female , Fetus/anatomy & histology , Mice , Pregnancy , Rabbits , Rats , Species SpecificityABSTRACT
In 45 control rats and 47 nephrectomized, DOCA-implanted, hypertensive rats (hypertensive phase), blood pressure, weight gain, development of pathologic-anatomical histological changes as well as changes in the myocardial enzyme pattern were studied over 24 weeks and after absorption of the DOCA tablet the return of the animals to normal conditions (follow-up phase) for another 14 weeks. During the hypertensive phase, blood pressure rose to 233 mm Hg on the average within 10 weeks and remained constant up to the 22nd week. In the follow-up phase, it dropped sharply, at first, and then slowly returned to normal. Weight gain was the same in DOCA and control rats. Relative weights of heart, kidneys and liver were elevated in the hypertensive phase but fell again in the follow-up phase. The pathologic-histological changes formed in the hypertensive phase, such as myocardial hypertrophy, glomerular hyalinization, tubular dilation and perivascular fibrosis, were remitted in part. Unchanged, however, the enhanced heart score persisted evidencing a proliferative vasoconstriction. Except for a pronounced, reversible increase in MAO activity, the cardial enzyme pattern remained unchanged during the experiment.
