The effects of SU-4885 on the rat adrenal cortex by oral administration of 50mg/kg, single or daily for 10 days, were morphologically studied particularly with histochemical methods for the enzyme and lipid.
Lipid depletion with fragmentation of droplets throughout the zona fasciculata in rats with single administration conformed to the pattern of adreno-cortical response to an acute moderate stimulus.
Reduced activity of secondary alcohol dehydrogenase, fragmentation of lipid droplets, and acidophilic and trabecular changes in the cell cords were observed in the inner fasciculata following a single or daily administration for 10 days. The medication apparently brought about hypersecretion of adrenocortical steroids, which was similar to the effect of ACTH administration.
Reduced activity of secondary alcohol dehydrogenase, which reflected the transformation of cholesterol in the steroid biosynthesis, was always observed in the zona fasciculata following the administration of SU-4885 or ACTH. The result might indicate that the administration inhibits some decrease in the steroid biosynthesis from cholesterol possibly through the ‘short route’.