HISTOCHEMICAL DISTRIBUTION OF THE SECONDARY ALCOHOL DEHYDROGENASE IN THE RAT, ESPECIALLY IN THE ADRENAL CORTEX

Abstract

In the site of steroid production, the histochemical activity of secondary alcohol dehydrogenase on isopropanol as its substrate with NAD as its coenzyme will reflect the inversion of 20ƒ?-22R-dihydroxycholesterol in the biosynthesis of steroid hormone, We applied this method on organs from all parts of the body of Wistar strain rats and observed positive reaction in the adrenal cortex, ovary and testis. In the adrenal cortex of mature rats, the zona glomerulosa exhibited a weakly positive activity, the outer to middle portions of the zona fasciculata an intensely positive activity, the inner portion of the zona fasciculata a weakly positive or negative activity, and the zona reticularis a positive activity. A proportional relationship between secondary alcohol dehydrogenase activity and the amount of lipid was present in the adrenal cortex of mature rats. In addition, the specific distribution of young and old rats was described. The secondary alcohol dehydrogenase is the enzyme of dehydration on the secondary alcohol. In 1965, Hardonkl' noted the similarity between the enzymes participating in the oxidative cleavage of the side chain of cholesterol as a precursor of steroid and secondary alcohol dehydrogenase. Using various secondary alcohols, the distribution of activity of the dehydrogenase in the human body was studied. Among them an enzyme acting on isopropanol as its substrate with nicotinamideadenine dinucleotide (NAD) as its coenzyme had a distribution of activity in the human body in agreement with the site of steroid production such as the adrenal cortex, ovary and testis, according to the description of Hardonkl'. The histochemical detection of various enzymes participating in the biosynthesis and metabolism of steroid hormones in the adrenal cortex and other tissues has been carried out on steroid-3/9-o1 dehydrogenase6', glucose-6-phosphate dehydrogenase and other enzymes2>''4). However, when no specific significance has yet been established, the secondary alcohol dehydrogenase activity will be important, too. We applied this method on organs from all parts of the body, particulary the site of steroid production of male and female Wistar rats, considering the relationship between this enzyme activity and lipid stain.