caa a22 4500 465765955 CHVBK 20180323111913.0 cr unu---uuuuu 170327e19901201xx s 000 0 eng 10.1007/BF02535896 doi (NATIONALLICENCE)springer-10.1007/BF02535896 Properties of an acid cholesteryl ester hydrolase inhibitor from rat serum [Elektronische Daten] [Mitsuo Tanaka, Toshihiro Iio, Toshikazu Tabata] The inhibitory effect of a protein isolated from rat serum on lysosomal acid cholesteryl ester hydrolase (acid CEH; EC.3.1.1.13) activity was studied. An inhibitor was purified from rat serum following ultracentrifugation and heat treatment using column chromatography on Sephacryl S-200 and ultrafiltration. The purified inhibitor appeared as a single protein band in sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis. The molecular weight of the inhibitor was 28,000 Daltons as judged by gel filtration on Sephacryl S-200 and SDS-polyacrylamide gel electrophoresis. The purified inhibitor was shown to be apolipoprotein A-I (apo A-I), the major apolipoprotein of high-density lipoprotein (HDL), using immunoprecipitation with rat anti-apo A-I immunoglobulin (Ig)G. Inhibition of acid CEH activity by apo A-I was dependent on the concentration of apo A-I. The values of Vmax obtained were similar with or without apo A-I. Apo A-I of various other mammalian species, including human, bovine and rabbit, also inhibited acid CEH activity. Other apolipoproteins, such as apo A-II and apo B, also showed inhibiting activity. On the other hand, apo A-I had no effect on the activity of other enzymes found in lysosomes, such as cathepsin D, β-glucuronidase and acid phosphatase. The results suggest that apolipoproteins may play a role in the regulation of hydrolysis of cholesteryl esters in lipoproteins, that have been transferred to the liver, and that the inhibition of acid CEH activity by apo A-I may be a characteristic of the lipid-binding protein or be due to changes of the lipid/water interface. American Oil Chemists' Society, 1990 Tanaka Mitsuo Showa College of Pharmaceutical Sciences, 3-3165, Higashi-tamagawagakuen, 194, Machida-City, Tokyo, Japan aut Iio Toshihiro Showa College of Pharmaceutical Sciences, 3-3165, Higashi-tamagawagakuen, 194, Machida-City, Tokyo, Japan aut Tabata Toshikazu Showa College of Pharmaceutical Sciences, 3-3165, Higashi-tamagawagakuen, 194, Machida-City, Tokyo, Japan aut Lipids Springer-Verlag 25/12(1990-12-01), 775-778 0024-4201 25:12<775 1990 25 11745 https://doi.org/10.1007/BF02535896 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF02535896 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Tanaka Mitsuo Showa College of Pharmaceutical Sciences, 3-3165, Higashi-tamagawagakuen, 194, Machida-City, Tokyo, Japan aut NATIONALLICENCE 700 1- Iio Toshihiro Showa College of Pharmaceutical Sciences, 3-3165, Higashi-tamagawagakuen, 194, Machida-City, Tokyo, Japan aut NATIONALLICENCE 700 1- Tabata Toshikazu Showa College of Pharmaceutical Sciences, 3-3165, Higashi-tamagawagakuen, 194, Machida-City, Tokyo, Japan aut NATIONALLICENCE 773 0- Lipids Springer-Verlag 25/12(1990-12-01), 775-778 0024-4201 25:12<775 1990 25 11745 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer