[Age-dependent biochemical studies on the extrarenal effect of furosemid (author's transl)]

The present study investigated the activities of lysosomal enzymes of the liver after administration of Furosemid. 10 weeks and 1-year old male albino rats were treated with 40 mg Furosemid for 4 subsequent days. According to the method devised by de Duve a sediment rich in lysosomes was produced by fractionated centrifugation and subsequently the enzyme activity of beta-glucuronidase, beta-acetylglucosaminidase, cathepsin D and a collagenolytic enzyme was measured in the sediment as well as in the corresponding lysosomal supernatant. The protein content served as a reference for the enzyme activities. In addition, we investigated the activities of cytoplasmic enzymes such as GOT, GPT, gamma-GT and the alkaline phosphatase. The enzyme activity changes were age-dependent. With Furosemid treatment the activities of beta-glucuronidase and cathepsin D increased in the lysosomal supernatant and the lysosomal sediment of the 1-year old rats, whereas the activities of the collagenolytic enzyme increased in the lysosomal sediment of the same group. In the lysosomal sediment of the 10-weeks old rats a decrease of beta-glucuronidase, beta-acetylglucosaminidase and cathepsin D was observed. These results are discussed in the light of reports from the literature.