One of the first steps in the biosynthesis of cholesterol from acetic acid is catalyzation by mevalonate pyrophosphate

from acetic acid is catalyzation by mevalonate pyrophosphate decarboxylase (MPD). This decarboxylase catalyzes a bimolecular reaction between mevalonate 5-pyrophosphate (MVAPP) and ATP to form isopentenyl pyrophosphate, inorganic phosphate, adenosine-5 -diphosphate (ADP), and CO2. MPD has been purified from various sources, including yeast, latex of Hevea brasiliensis, pig liver, rat liver, mouse liver, and chicken liver. Its properties in rats and chickens have been examined in detail. Toth and Huwyler reported cDNA sequences of MPD from human liver and yeast. The recombinant human enzyme is a homodimer of 43-kDa subunits with 400 amino acids. We recently established a procedure for purifying MPD from the liver of rats fed a diet containing 5% cholestyramine and 0.1% pravastatin using chromatography and polyclonal antiserum raised against rat MPD. We also previously reported that a high level of MPD was observed in the mouse kidney, as compared with rats. It has not been found whether a high level of MPD was observed in the kidney of other species or whether anti-rat MPD antiserum reacted with MPD of other species other than mice. In the present study, we found the tissue distribution of MPD in guinea pigs, after confirming that anti-rat MPD antiserum reacted with MPD of guinea pigs.