1. The activities of @entity29709 thiolase, @entity2453 synthase and lyase and @entity29709 deacylase were measured in homogenates of samples of liver, rumen epithelium ( @entity1829 ), kidney and lactating mammary gland derived from slaughtered @entity291 . 2. The activities of the four enzymes in @entity291 liver were similar to the activities previously reported for the corresponding enzymes in @entity35 liver. 3. @entity29709 thiolase and @entity2453 synthase and lyase were present in rumen epithelium. The activities of the enzymes were all lower on a wet weight basis than in liver. Only very slight deacylase activity was detected. 4. Kidney contained @entity29709 thiolase, @entity2453 lyase and @entity29709 deacylase, but only trace amounts of @entity2453 synthase. 5. Mammary gland contained @entity29709 thiolase and some @entity2453 lyase, but virtually no @entity2453 synthase or @entity29709 deacylase. 6. Since physiologically significant ketogenesis probably occurs solely via the @entity2453 pathway, it is evident that, of the four tissues examined, such ketogenesis must be restricted to the liver and the rumen epithelium. 7. All the enzymes except @entity2453 lyase were also assayed in the four tissues derived from @entity291 suffering from @entity291 lactational ketosis. Ketosis did not cause a statistically significant change in the activity of any of the enzymes measured. 8. Hepatic @entity2453 synthase and lyase were found to be associated mainly with the particulate fraction, as in the @entity35 . A considerably greater proportion of these enzymes was found to be present in the cytoplasmic fraction from rumen epithelium, although it was not excluded that this was due to @entity2383 during homogenization. 9. Appreciable @entity2453 synthase was also present in epithelium from the dorsal region of the rumen, from the reticulum and from the omasum, but not from the abomasum.

Enzymes involved in acetoacetate formation in various XXXX tissues.

@entity35 :: ('10116', 'Species') :: ['rat'] @entity1829 :: ('MESH:D010211', 'Disease') :: ['long papillae'] @entity29709 :: ('MESH:C010667', 'Chemical') :: ['acetoacetyl-CoA', 'Acetoacetyl-CoA'] @entity291 :: ('9913', 'Species') :: ['cows', 'bovine'] @entity2453 :: ('MESH:C008047', 'Chemical') :: ['hydroxymethylglutaryl-CoA'] @entity2383 :: ('MESH:D028361', 'Disease') :: ['mitochondrial damage']
@entity291 :: (9913,Species) :: ['bovine']
