Abstract
Experiments were done on the biosynthesis of CoA from pantothenic acid, in vivo. Young albino rats were fed on various levels of pantothenate or pantethine as 0,0.45,2.3,9.2,23.0 and 230.0 μ moles supplementation per 100g of pantothenic acid deficient diet. Hepatic CoA and its precursors (dephospho-CoA and 4'-phosphopantetheine), bound and free pantothenic acids were determined. 1) When rats were fed on deficient diet, both CoA and its precursors in liver decreased. 2) The liver CoA content was highest when deficient diet was supplemented with 9.2 μmoles per 100g of pantothenate or pantethine. 3) When the deficient diet supplemented with 2.3-23.0 μmoles of pantothenate or pantethine was administered, the contents of precursors in liver were almost equal to those of CoA. Such a finding that rat liver contains considerably larger amount of CoA precursors is quitely different from Novelli's conclusion in which he mentioned that almost all the bound pantothenic acid was CoA itself. 4) No difference between the liver CoA contents of pantothenate and of pantethine-supplemented groups, but the ratio of CoA to total pantothenic acid was always higher in pantethine-supplemented groups.
