Abstract
The metabolic pattern and the sparing effect of vitamin B_<12> were studied in pantothenic acid deficiency in the rat and the following results were obtained : a) The liver of pantothenic acid deficient rat had higher vitamin B_<12> content than the control, but the plasma vitamin B_<12> level was not elevated in pantothenic acid deficiency. b) Administration of a large dose of vitamin B_<12> to rats receiving suboptimal dose of pantothenic acid had sparing effect on the survival rate. c) Absorption and excretion of radioactive vitamin B_<12> was not impaired in pantothenic acid deficiency. d) Radioactive vitamin B_<12> introduced either by intestinal absorption or by injection was retained more in the liver on gram basis in pantothenic acid deficient rats than the normal. It was proposed from the evidence presented that these two vitamins are closely interrelated in the intermediary metabolism, and that in pantothenic acid deficiency the utilization of vitamin B_<12> is impaired to result in elevated liver vitamin B_<12> levels.
