Studies on the Blood Pyridoxine of Vitamin B6 Deficient Monkeys.

Abstract
Suitable modifications for the extraction and assay of blood pyridoxine are described. The vitamin B6 levels of 14 rhesus monkeys were followed before and after withdrawal of the vitamin from the diet. The vitamin B6 levels fell during the first 2 weeks of deprivation. This usually brought the levels down to values of 2-3 μg per 100 ml of whole blood or lower, where they remained throughout the rest of the experiment for periods exceeding 1 year. Control animals on a daily intake of equivalent to 1 mg of pyridoxine hydrochloric acid had values ranging horn 5.0 to 20.8 μg, averaging 11.2. Some of the changes observed in deficient animals are discussed.